Terjemahan disediakan oleh mesin penerjemah. Jika konten terjemahan yang diberikan bertentangan dengan versi bahasa Inggris aslinya, utamakan versi bahasa Inggris. # Tutorial Amazon QLDB Java **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Dalam implementasi aplikasi contoh tutorial ini, Anda menggunakan driver Amazon QLDB dengan AWS SDK untuk Java untuk membuat buku besar QLDB dan mengisinya dengan data sampel. Saat Anda mengerjakan tutorial ini, Anda dapat merujuk ke [Referensi AWS SDK untuk Java API](https://docs.aws.amazon.com/sdk-for-java/latest/reference/) untuk operasi API manajemen. Untuk operasi data transaksional, Anda dapat merujuk ke Driver QLDB untuk Referensi [API Java](https://javadoc.io/doc/software.amazon.qldb/amazon-qldb-driver-java/latest/index.html). **catatan** Jika berlaku, beberapa langkah tutorial memiliki perintah atau contoh kode yang berbeda untuk setiap versi utama yang didukung dari driver QLDB untuk Java. **Topics** + [ # Menginstal aplikasi sampel Amazon QLDB Java ](sample-app.java.md) + [ # Langkah 1: Buat buku besar baru ](getting-started.java.step-1.md) + [ # Langkah 2: Uji konektivitas ke buku besar ](getting-started.java.step-2.md) + [ # Langkah 3: Buat tabel, indeks, dan data sampel ](getting-started.java.step-3.md) + [ # Langkah 4: Kueri tabel dalam buku besar ](getting-started.java.step-4.md) + [ # Langkah 5: Ubah dokumen dalam buku besar ](getting-started.java.step-5.md) + [ # Langkah 6: Lihat riwayat revisi untuk dokumen ](getting-started.java.step-6.md) + [ # Langkah 7: Verifikasi dokumen dalam buku besar ](getting-started.java.step-7.md) + [ # Langkah 8: Ekspor dan validasi data jurnal dalam buku besar ](getting-started.java.step-8.md) + [ # Langkah 9 (opsional): Bersihkan sumber daya ](getting-started.java.step-9.md) # Menginstal aplikasi sampel Amazon QLDB Java **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Bagian ini menjelaskan cara menginstal dan menjalankan aplikasi sampel Amazon QLDB yang disediakan untuk step-by-step tutorial Java. Kasus penggunaan untuk aplikasi sampel ini adalah database departemen kendaraan bermotor (DMV) yang melacak informasi historis lengkap tentang pendaftaran kendaraan. [Contoh aplikasi DMV untuk Java adalah open source di GitHub repositori aws-samples/ -java. amazon-qldb-dmv-sample](https://github.com/aws-samples/amazon-qldb-dmv-sample-java) ## Prasyarat Sebelum Anda memulai, pastikan Anda menyelesaikan driver QLDB untuk Java. [Prasyarat](getting-started.java.md#getting-started.java.prereqs) Ini termasuk yang berikut: 1. Mendaftar untuk AWS. 1. Buat pengguna dengan izin QLDB yang sesuai. Untuk menyelesaikan semua langkah dalam tutorial ini, Anda memerlukan akses administratif penuh ke sumber daya buku besar Anda melalui QLDB API. 1. Jika Anda menggunakan IDE selain AWS Cloud9, instal Java dan berikan akses terprogram untuk pengembangan. ## Penginstalan Langkah-langkah berikut menjelaskan cara mengunduh dan mengatur aplikasi sampel dengan lingkungan pengembangan lokal. Atau, Anda dapat mengotomatiskan penyiapan aplikasi sampel dengan menggunakan AWS Cloud9 sebagai IDE Anda, dan CloudFormation templat untuk menyediakan sumber daya pengembangan Anda. ### Lingkungan pembangunan lokal Petunjuk ini menjelaskan cara mengunduh dan menginstal aplikasi sampel QLDB Java menggunakan sumber daya dan lingkungan pengembangan Anda sendiri. **Untuk mengunduh dan menjalankan aplikasi sampel** 1. Masukkan perintah berikut untuk mengkloning aplikasi sampel dari GitHub. ------ #### [ 2.x ] ``` git clone https://github.com/aws-samples/amazon-qldb-dmv-sample-java.git ``` ------ #### [ 1.x ] ``` git clone -b v1.2.0 https://github.com/aws-samples/amazon-qldb-dmv-sample-java.git ``` ------ Paket ini mencakup konfigurasi Gradle dan kode lengkap dari file. [Tutorial Java](getting-started.java.tutorial.md) 1. Muat dan jalankan aplikasi yang disediakan. + Jika Anda menggunakan Eclipse: 1. **Mulai Eclipse, dan pada menu **Eclipse**, pilih **File**, **Impor**, dan kemudian Existing Gradle Project.** 1. Di direktori root proyek, telusuri dan pilih direktori aplikasi yang berisi `build.gradle` file. Kemudian, pilih **Selesai** untuk menggunakan pengaturan Gradle default untuk impor. 1. Anda dapat mencoba menjalankan `ListLedgers` program sebagai contoh. Buka menu konteks (klik kanan) untuk `ListLedgers.java` file tersebut, dan pilih **Jalankan sebagai Aplikasi Java**. + Jika Anda menggunakan IntelliJ: 1. ****Mulai IntelliJ, dan pada menu **IntelliJ**, pilih File lalu Buka.**** 1. Di direktori root proyek, telusuri dan pilih direktori aplikasi yang berisi `build.gradle` file. Kemudian, pilih **OK**. Pertahankan pengaturan default, dan pilih **OK** lagi. 1. Anda dapat mencoba menjalankan `ListLedgers` program sebagai contoh. Buka menu konteks (klik kanan) untuk `ListLedgers.java` file tersebut, dan pilih **Jalankan 'ListLedgers'**. 1. Lanjutkan [Langkah 1: Buat buku besar baru](getting-started.java.step-1.md) untuk memulai tutorial dan membuat buku besar. ### AWS Cloud9 Instruksi ini menjelaskan cara mengotomatiskan pengaturan aplikasi sampel registrasi kendaraan QLDB Amazon untuk Java, [AWS Cloud9](https://aws.amazon.com/cloud9)menggunakan sebagai IDE Anda. Dalam panduan ini, Anda menggunakan [CloudFormation](https://aws.amazon.com/cloudformation)template untuk menyediakan sumber daya pengembangan Anda. Untuk informasi selengkapnya AWS Cloud9, lihat [Panduan AWS Cloud9 Pengguna](https://docs.aws.amazon.com/cloud9/latest/user-guide/). Untuk mempelajari selengkapnya CloudFormation, lihat [Panduan AWS CloudFormation Pengguna](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/). **Topics** + [ #### Bagian 1: Menyediakan sumber daya Anda ](#sample-app.java.cfn-ac9.step-1) + [ #### Bagian 2: Siapkan IDE Anda ](#sample-app.java.cfn-ac9.step-2) + [ #### Bagian 3: Jalankan aplikasi sampel QLDB DMV ](#sample-app.java.cfn-ac9.step-3) #### Bagian 1: Menyediakan sumber daya Anda Pada langkah pertama ini, Anda gunakan CloudFormation untuk menyediakan sumber daya yang diperlukan untuk menyiapkan lingkungan pengembangan Anda dengan contoh aplikasi Amazon QLDB. **Untuk membuka CloudFormation konsol dan memuat templat aplikasi sampel QLDB** 1. Masuk ke Konsol Manajemen AWS dan buka CloudFormation konsol di [https://console.aws.amazon.com/cloudformation](https://console.aws.amazon.com/cloudformation/). Beralih ke Wilayah yang mendukung QLDB. Untuk daftar lengkapnya, lihat [titik akhir QLDB Amazon](https://docs.aws.amazon.com/general/latest/gr/qldb.html) dan kuota di. *Referensi Umum AWS* Tangkapan layar berikut Konsol Manajemen AWS menunjukkan US East (Virginia N.) sebagai yang dipilih Wilayah AWS. ![\[Konsol Manajemen AWS menunjukkan US East (Virginia N.) sebagai yang terpilih Wilayah AWS.\]](http://docs.aws.amazon.com/id_id/qldb/latest/developerguide/images/cfn-ac9/aws-region-us-east-1.png) 1. Di CloudFormation konsol, pilih **Buat tumpukan**, lalu pilih **Dengan sumber daya baru (standar)**. 1. Pada halaman **Buat tumpukan** di bawah **Tentukan template**, pilih **URL Amazon S3**. 1. Masukkan URL berikut, dan pilih **Berikutnya**. ``` https://amazon-qldb-assets.s3.amazonaws.com/templates/QLDB-DMV-SampleApp.yml ``` 1. Masukkan **nama Stack** (seperti**qldb-sample-app**), dan pilih **Next**. 1. Anda dapat menambahkan tag apa pun yang sesuai dan menyimpan opsi default. Lalu pilih **Berikutnya**. 1. Tinjau pengaturan tumpukan Anda, dan pilih **Buat tumpukan**. CloudFormation Skrip mungkin membutuhkan waktu beberapa menit untuk menyelesaikannya. Skrip ini menyediakan AWS Cloud9 lingkungan Anda dengan instance Amazon Elastic Compute Cloud (Amazon EC2) terkait yang Anda gunakan untuk menjalankan contoh aplikasi QLDB dalam tutorial ini. Itu juga mengkloning repositori [aws-samples/ amazon-qldb-dmv-sample -java](https://github.com/aws-samples/amazon-qldb-dmv-sample-java/) dari ke lingkungan pengembangan Anda. GitHub AWS Cloud9 #### Bagian 2: Siapkan IDE Anda Pada langkah ini, Anda menyelesaikan pengaturan lingkungan pengembangan cloud Anda. Anda mengunduh dan menjalankan skrip shell yang disediakan untuk menyiapkan AWS Cloud9 IDE Anda dengan contoh dependensi aplikasi. **Untuk mengatur AWS Cloud9 lingkungan Anda** 1. Buka AWS Cloud9 konsol di [https://console.aws.amazon.com/cloud9/](https://console.aws.amazon.com/cloud9/). 1. **Di bawah **lingkungan Anda**, cari kartu untuk lingkungan bernama **QLDB DMV Sample** Application, dan pilih Open IDE.** Lingkungan Anda mungkin membutuhkan waktu satu menit untuk dimuat saat EC2 instance yang mendasarinya diluncurkan. AWS Cloud9 Lingkungan Anda sudah dikonfigurasi sebelumnya dengan dependensi sistem yang Anda butuhkan untuk menjalankan tutorial. Di panel navigasi **Lingkungan** konsol Anda, konfirmasikan bahwa Anda melihat folder bernama`QLDB DMV Sample Application`. Tangkapan layar AWS Cloud9 konsol berikut menunjukkan panel folder lingkungan Aplikasi Sampel QLDB DMV. ![\[AWS Cloud9 konsol yang menampilkan panel folder lingkungan Aplikasi Sampel QLDB DMV.\]](http://docs.aws.amazon.com/id_id/qldb/latest/developerguide/images/cfn-ac9/cloud9-folders.png) Jika Anda tidak melihat panel navigasi, alihkan tab **Lingkungan** di sisi kiri konsol Anda. Jika Anda tidak melihat folder apa pun di panel, aktifkan **Show Environment Root** menggunakan ikon pengaturan (![\[Settings icon\]](http://docs.aws.amazon.com/id_id/qldb/latest/developerguide/images/settings.png)). 1. Di panel bawah konsol Anda, Anda akan melihat jendela `bash` terminal yang terbuka. Jika Anda tidak melihat ini, pilih **Terminal Baru** dari menu **Jendela** di bagian atas konsol Anda. 1. Selanjutnya, unduh dan jalankan skrip penyiapan untuk menginstal OpenJDK 8 dan—jika berlaku—periksa cabang yang sesuai dari repositori Git. Di AWS Cloud9 terminal yang Anda buat pada langkah sebelumnya, jalankan dua perintah berikut secara berurutan: ------ #### [ 2.x ] ``` aws s3 cp s3://amazon-qldb-assets/setup-scripts/dmv-setup-v2.sh . ``` ``` sh dmv-setup-v2.sh ``` ------ #### [ 1.x ] ``` aws s3 cp s3://amazon-qldb-assets/setup-scripts/dmv-setup.sh . ``` ``` sh dmv-setup.sh ``` ------ Setelah selesai, Anda akan melihat pesan berikut dicetak di terminal: ``` ** DMV Sample App setup completed , enjoy!! ** ``` 1. Luangkan waktu sejenak untuk menelusuri contoh kode aplikasi AWS Cloud9, terutama di jalur direktori berikut:`src/main/java/software/amazon/qldb/tutorial`. #### Bagian 3: Jalankan aplikasi sampel QLDB DMV Pada langkah ini, Anda mempelajari cara menjalankan tugas aplikasi sampel Amazon QLDB DMV menggunakan. AWS Cloud9 Untuk menjalankan kode sampel, kembali ke AWS Cloud9 terminal Anda atau buat jendela terminal baru seperti yang Anda lakukan di *Bagian 2: Siapkan IDE Anda*. **Untuk menjalankan aplikasi sampel** 1. Jalankan perintah berikut di terminal Anda untuk beralih ke direktori root proyek: ``` cd ~/environment/amazon-qldb-dmv-sample-java ``` Pastikan Anda menjalankan contoh di jalur direktori berikut. ``` /home/ec2-user/environment/amazon-qldb-dmv-sample-java/ ``` 1. Perintah berikut menunjukkan sintaks Gradle untuk menjalankan setiap tugas. ``` ./gradlew run -Dtutorial=Task ``` Misalnya, jalankan perintah berikut untuk mencantumkan semua buku besar di Wilayah Anda Akun AWS dan saat ini. ``` ./gradlew run -Dtutorial=ListLedgers ``` 1. Lanjutkan [Langkah 1: Buat buku besar baru](getting-started.java.step-1.md) untuk memulai tutorial dan membuat buku besar. 1. (Opsional) Setelah Anda menyelesaikan tutorial, bersihkan CloudFormation sumber daya Anda jika Anda tidak lagi membutuhkannya. 1. Buka CloudFormation konsol di [https://console.aws.amazon.com/cloudformation](https://console.aws.amazon.com/cloudformation/), dan hapus tumpukan yang Anda buat di *Bagian 1: Menyediakan* Sumber Daya Anda. 1. Hapus juga AWS Cloud9 tumpukan yang dibuat CloudFormation template untuk Anda. # Langkah 1: Buat buku besar baru **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Pada langkah ini, Anda membuat buku besar Amazon QLDB baru bernama. `vehicle-registration` **Untuk membuat buku besar baru** 1. Tinjau file berikut (`Constants.java`), yang berisi nilai konstan yang digunakan oleh semua program lain dalam tutorial ini. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonSystem; import com.amazon.ion.system.IonSystemBuilder; import com.fasterxml.jackson.databind.SerializationFeature; import com.fasterxml.jackson.dataformat.ion.IonObjectMapper; import com.fasterxml.jackson.dataformat.ion.ionvalue.IonValueMapper; /** * Constant values used throughout this tutorial. */ public final class Constants { public static final int RETRY_LIMIT = 4; public static final String LEDGER_NAME = "vehicle-registration"; public static final String STREAM_NAME = "vehicle-registration-stream"; public static final String VEHICLE_REGISTRATION_TABLE_NAME = "VehicleRegistration"; public static final String VEHICLE_TABLE_NAME = "Vehicle"; public static final String PERSON_TABLE_NAME = "Person"; public static final String DRIVERS_LICENSE_TABLE_NAME = "DriversLicense"; public static final String VIN_INDEX_NAME = "VIN"; public static final String PERSON_GOV_ID_INDEX_NAME = "GovId"; public static final String VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME = "LicensePlateNumber"; public static final String DRIVER_LICENSE_NUMBER_INDEX_NAME = "LicenseNumber"; public static final String DRIVER_LICENSE_PERSONID_INDEX_NAME = "PersonId"; public static final String JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX = "qldb-tutorial-journal-export"; public static final String USER_TABLES = "information_schema.user_tables"; public static final String LEDGER_NAME_WITH_TAGS = "tags"; public static final IonSystem SYSTEM = IonSystemBuilder.standard().build(); public static final IonObjectMapper MAPPER = new IonValueMapper(SYSTEM); private Constants() { } static { MAPPER.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS); } } ``` ------ #### [ 1.x ] **penting** Untuk paket Amazon Ion, Anda harus menggunakan namespace `com.amazon.ion` di aplikasi Anda. AWS SDK untuk Java Tergantung pada paket Ion lain di bawah namespace`software.amazon.ion`, tetapi ini adalah paket lama yang tidak kompatibel dengan driver QLDB. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonSystem; import com.amazon.ion.system.IonSystemBuilder; import com.fasterxml.jackson.databind.SerializationFeature; import com.fasterxml.jackson.dataformat.ion.IonObjectMapper; import com.fasterxml.jackson.dataformat.ion.ionvalue.IonValueMapper; /** * Constant values used throughout this tutorial. */ public final class Constants { public static final int RETRY_LIMIT = 4; public static final String LEDGER_NAME = "vehicle-registration"; public static final String STREAM_NAME = "vehicle-registration-stream"; public static final String VEHICLE_REGISTRATION_TABLE_NAME = "VehicleRegistration"; public static final String VEHICLE_TABLE_NAME = "Vehicle"; public static final String PERSON_TABLE_NAME = "Person"; public static final String DRIVERS_LICENSE_TABLE_NAME = "DriversLicense"; public static final String VIN_INDEX_NAME = "VIN"; public static final String PERSON_GOV_ID_INDEX_NAME = "GovId"; public static final String VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME = "LicensePlateNumber"; public static final String DRIVER_LICENSE_NUMBER_INDEX_NAME = "LicenseNumber"; public static final String DRIVER_LICENSE_PERSONID_INDEX_NAME = "PersonId"; public static final String JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX = "qldb-tutorial-journal-export"; public static final String USER_TABLES = "information_schema.user_tables"; public static final String LEDGER_NAME_WITH_TAGS = "tags"; public static final IonSystem SYSTEM = IonSystemBuilder.standard().build(); public static final IonObjectMapper MAPPER = new IonValueMapper(SYSTEM); private Constants() { } static { MAPPER.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS); } } ``` ------ **catatan** `Constants`Kelas ini mencakup contoh `IonValueMapper` kelas Jackson open-source. Anda dapat menggunakan mapper ini untuk memproses data [Amazon Ion](ion.md) Anda saat melakukan transaksi baca dan tulis. `CreateLedger.java`File ini juga memiliki ketergantungan pada program berikut (`DescribeLedger.java`), yang menjelaskan status buku besar Anda saat ini. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.model.DescribeLedgerRequest; import com.amazonaws.services.qldb.model.DescribeLedgerResult; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Describe a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class DescribeLedger { public static AmazonQLDB client = CreateLedger.getClient(); public static final Logger log = LoggerFactory.getLogger(DescribeLedger.class); private DescribeLedger() { } public static void main(final String... args) { try { describe(Constants.LEDGER_NAME); } catch (Exception e) { log.error("Unable to describe a ledger!", e); } } /** * Describe a ledger. * * @param name * Name of the ledger to describe. * @return {@link DescribeLedgerResult} from QLDB. */ public static DescribeLedgerResult describe(final String name) { log.info("Let's describe ledger with name: {}...", name); DescribeLedgerRequest request = new DescribeLedgerRequest().withName(name); DescribeLedgerResult result = client.describeLedger(request); log.info("Success. Ledger description: {}", result); return result; } } ``` 1. Kompilasi dan jalankan `CreateLedger.java` program untuk membuat buku besar bernama. `vehicle-registration` ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.client.builder.AwsClientBuilder; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.AmazonQLDBClientBuilder; import com.amazonaws.services.qldb.model.CreateLedgerRequest; import com.amazonaws.services.qldb.model.CreateLedgerResult; import com.amazonaws.services.qldb.model.DescribeLedgerResult; import com.amazonaws.services.qldb.model.LedgerState; import com.amazonaws.services.qldb.model.PermissionsMode; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Create a ledger and wait for it to be active. *

* This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class CreateLedger { public static final Logger log = LoggerFactory.getLogger(CreateLedger.class); public static final Long LEDGER_CREATION_POLL_PERIOD_MS = 10_000L; public static String endpoint = null; public static String region = null; public static AmazonQLDB client = getClient(); private CreateLedger() { } /** * Build a low-level QLDB client. * * @return {@link AmazonQLDB} control plane client. */ public static AmazonQLDB getClient() { AmazonQLDBClientBuilder builder = AmazonQLDBClientBuilder.standard(); if (null != endpoint && null != region) { builder.setEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration(endpoint, region)); } return builder.build(); } public static void main(final String... args) throws Exception { try { client = getClient(); create(Constants.LEDGER_NAME); waitForActive(Constants.LEDGER_NAME); } catch (Exception e) { log.error("Unable to create the ledger!", e); throw e; } } /** * Create a new ledger with the specified ledger name. * * @param ledgerName Name of the ledger to be created. * @return {@link CreateLedgerResult} from QLDB. */ public static CreateLedgerResult create(final String ledgerName) { log.info("Let's create the ledger with name: {}...", ledgerName); CreateLedgerRequest request = new CreateLedgerRequest() .withName(ledgerName) .withPermissionsMode(PermissionsMode.ALLOW_ALL); CreateLedgerResult result = client.createLedger(request); log.info("Success. Ledger state: {}.", result.getState()); return result; } /** * Wait for a newly created ledger to become active. * * @param ledgerName Name of the ledger to wait on. * @return {@link DescribeLedgerResult} from QLDB. * @throws InterruptedException if thread is being interrupted. */ public static DescribeLedgerResult waitForActive(final String ledgerName) throws InterruptedException { log.info("Waiting for ledger to become active..."); while (true) { DescribeLedgerResult result = DescribeLedger.describe(ledgerName); if (result.getState().equals(LedgerState.ACTIVE.name())) { log.info("Success. Ledger is active and ready to use."); return result; } log.info("The ledger is still creating. Please wait..."); Thread.sleep(LEDGER_CREATION_POLL_PERIOD_MS); } } } ``` ------ #### [ 1.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.AmazonQLDBClientBuilder; import com.amazonaws.services.qldb.model.CreateLedgerRequest; import com.amazonaws.services.qldb.model.CreateLedgerResult; import com.amazonaws.services.qldb.model.DescribeLedgerResult; import com.amazonaws.services.qldb.model.LedgerState; import com.amazonaws.services.qldb.model.PermissionsMode; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Create a ledger and wait for it to be active. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class CreateLedger { public static final Logger log = LoggerFactory.getLogger(CreateLedger.class); public static final Long LEDGER_CREATION_POLL_PERIOD_MS = 10_000L; public static AmazonQLDB client = getClient(); private CreateLedger() { } /** * Build a low-level QLDB client. * * @return {@link AmazonQLDB} control plane client. */ public static AmazonQLDB getClient() { return AmazonQLDBClientBuilder.standard().build(); } public static void main(final String... args) throws Exception { try { create(Constants.LEDGER_NAME); waitForActive(Constants.LEDGER_NAME); } catch (Exception e) { log.error("Unable to create the ledger!", e); throw e; } } /** * Create a new ledger with the specified ledger name. * * @param ledgerName * Name of the ledger to be created. * @return {@link CreateLedgerResult} from QLDB. */ public static CreateLedgerResult create(final String ledgerName) { log.info("Let's create the ledger with name: {}...", ledgerName); CreateLedgerRequest request = new CreateLedgerRequest() .withName(ledgerName) .withPermissionsMode(PermissionsMode.ALLOW_ALL); CreateLedgerResult result = client.createLedger(request); log.info("Success. Ledger state: {}.", result.getState()); return result; } /** * Wait for a newly created ledger to become active. * * @param ledgerName * Name of the ledger to wait on. * @return {@link DescribeLedgerResult} from QLDB. * @throws InterruptedException if thread is being interrupted. */ public static DescribeLedgerResult waitForActive(final String ledgerName) throws InterruptedException { log.info("Waiting for ledger to become active..."); while (true) { DescribeLedgerResult result = DescribeLedger.describe(ledgerName); if (result.getState().equals(LedgerState.ACTIVE.name())) { log.info("Success. Ledger is active and ready to use."); return result; } log.info("The ledger is still creating. Please wait..."); Thread.sleep(LEDGER_CREATION_POLL_PERIOD_MS); } } } ``` ------ **catatan** Dalam `createLedger` panggilan, Anda harus menentukan nama buku besar dan mode izin. Sebaiknya gunakan mode `STANDARD` izin untuk memaksimalkan keamanan data buku besar Anda. Saat Anda membuat buku besar, *perlindungan penghapusan* diaktifkan secara default. Ini adalah fitur di QLDB yang mencegah buku besar dihapus oleh pengguna mana pun. Anda memiliki opsi untuk menonaktifkan perlindungan penghapusan pada pembuatan buku besar menggunakan QLDB API atau (). AWS Command Line Interface AWS CLI Secara opsional, Anda juga dapat menentukan tag untuk dilampirkan ke buku besar Anda. Untuk memverifikasi koneksi Anda ke buku besar baru, lanjutkan ke[Langkah 2: Uji konektivitas ke buku besar](getting-started.java.step-2.md). # Langkah 2: Uji konektivitas ke buku besar **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Pada langkah ini, Anda memverifikasi bahwa Anda dapat terhubung ke `vehicle-registration` buku besar di Amazon QLDB menggunakan titik akhir API data transaksional. **Untuk menguji konektivitas ke buku besar** 1. Tinjau program berikut (`ConnectToLedger.java`), yang membuat koneksi sesi data ke `vehicle-registration` buku besar. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.net.URI; import java.net.URISyntaxException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider; import software.amazon.awssdk.services.qldbsession.QldbSessionClient; import software.amazon.awssdk.services.qldbsession.QldbSessionClientBuilder; import software.amazon.qldb.QldbDriver; import software.amazon.qldb.RetryPolicy; /** * Connect to a session for a given ledger using default settings. *

* This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class ConnectToLedger { public static final Logger log = LoggerFactory.getLogger(ConnectToLedger.class); public static AwsCredentialsProvider credentialsProvider; public static String endpoint = null; public static String ledgerName = Constants.LEDGER_NAME; public static String region = null; public static QldbDriver driver; private ConnectToLedger() { } /** * Create a pooled driver for creating sessions. * * @param retryAttempts How many times the transaction will be retried in * case of a retryable issue happens like Optimistic Concurrency Control exception, * server side failures or network issues. * @return The pooled driver for creating sessions. */ public static QldbDriver createQldbDriver(int retryAttempts) { QldbSessionClientBuilder builder = getAmazonQldbSessionClientBuilder(); return QldbDriver.builder() .ledger(ledgerName) .transactionRetryPolicy(RetryPolicy .builder() .maxRetries(retryAttempts) .build()) .sessionClientBuilder(builder) .build(); } /** * Create a pooled driver for creating sessions. * * @return The pooled driver for creating sessions. */ public static QldbDriver createQldbDriver() { QldbSessionClientBuilder builder = getAmazonQldbSessionClientBuilder(); return QldbDriver.builder() .ledger(ledgerName) .transactionRetryPolicy(RetryPolicy.builder() .maxRetries(Constants.RETRY_LIMIT).build()) .sessionClientBuilder(builder) .build(); } /** * Creates a QldbSession builder that is passed to the QldbDriver to connect to the Ledger. * * @return An instance of the AmazonQLDBSessionClientBuilder */ public static QldbSessionClientBuilder getAmazonQldbSessionClientBuilder() { QldbSessionClientBuilder builder = QldbSessionClient.builder(); if (null != endpoint && null != region) { try { builder.endpointOverride(new URI(endpoint)); } catch (URISyntaxException e) { throw new IllegalArgumentException(e); } } if (null != credentialsProvider) { builder.credentialsProvider(credentialsProvider); } return builder; } /** * Create a pooled driver for creating sessions. * * @return The pooled driver for creating sessions. */ public static QldbDriver getDriver() { if (driver == null) { driver = createQldbDriver(); } return driver; } public static void main(final String... args) { Iterable tables = ConnectToLedger.getDriver().getTableNames(); log.info("Existing tables in the ledger:"); for (String table : tables) { log.info("- {} ", table); } } } ``` **catatan** Untuk menjalankan operasi data pada buku besar Anda, Anda harus membuat instance `QldbDriver` kelas untuk terhubung ke buku besar tertentu. Ini adalah objek klien yang berbeda dari `AmazonQLDB` klien yang Anda gunakan pada langkah sebelumnya untuk membuat buku besar. Klien sebelumnya hanya digunakan untuk menjalankan operasi API manajemen yang tercantum dalam[Referensi API QLDB Amazon](api-reference.md). Pertama, buat `QldbDriver` objek. Anda harus menentukan nama buku besar saat Anda membuat driver ini. Kemudian, Anda dapat menggunakan `execute` metode driver ini untuk menjalankan pernyataan PartiQL. Secara opsional, Anda dapat menentukan jumlah maksimum percobaan ulang untuk pengecualian transaksi. `execute`Metode ini secara otomatis mencoba kembali konflik kontrol konkurensi optimis (OCC) dan pengecualian sementara umum lainnya hingga batas yang dapat dikonfigurasi ini. Nilai default-nya adalah `4`. Jika transaksi masih gagal setelah batas tercapai, maka pengemudi melempar pengecualian. Untuk mempelajari selengkapnya, lihat [Memahami kebijakan coba lagi dengan pengemudi di Amazon QLDB](driver-retry-policy.md). ------ #### [ 1.x ] ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.auth.AWSCredentialsProvider; import com.amazonaws.client.builder.AwsClientBuilder; import com.amazonaws.services.qldbsession.AmazonQLDBSessionClientBuilder; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.PooledQldbDriver; import software.amazon.qldb.QldbDriver; import software.amazon.qldb.QldbSession; import software.amazon.qldb.exceptions.QldbClientException; /** * Connect to a session for a given ledger using default settings. *

* This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class ConnectToLedger { public static final Logger log = LoggerFactory.getLogger(ConnectToLedger.class); public static AWSCredentialsProvider credentialsProvider; public static String endpoint = null; public static String ledgerName = Constants.LEDGER_NAME; public static String region = null; private static PooledQldbDriver driver; private ConnectToLedger() { } /** * Create a pooled driver for creating sessions. * * @return The pooled driver for creating sessions. */ public static PooledQldbDriver createQldbDriver() { AmazonQLDBSessionClientBuilder builder = AmazonQLDBSessionClientBuilder.standard(); if (null != endpoint && null != region) { builder.setEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration(endpoint, region)); } if (null != credentialsProvider) { builder.setCredentials(credentialsProvider); } return PooledQldbDriver.builder() .withLedger(ledgerName) .withRetryLimit(Constants.RETRY_LIMIT) .withSessionClientBuilder(builder) .build(); } /** * Create a pooled driver for creating sessions. * * @return The pooled driver for creating sessions. */ public static PooledQldbDriver getDriver() { if (driver == null) { driver = createQldbDriver(); } return driver; } /** * Connect to a ledger through a {@link QldbDriver}. * * @return {@link QldbSession}. */ public static QldbSession createQldbSession() { return getDriver().getSession(); } public static void main(final String... args) { try (QldbSession qldbSession = createQldbSession()) { log.info("Listing table names "); for (String tableName : qldbSession.getTableNames()) { log.info(tableName); } } catch (QldbClientException e) { log.error("Unable to create session.", e); } } } ``` **catatan** Untuk menjalankan operasi data pada buku besar Anda, Anda harus membuat instance `QldbDriver` kelas `PooledQldbDriver` atau untuk terhubung ke buku besar tertentu. Ini adalah objek klien yang berbeda dari `AmazonQLDB` klien yang Anda gunakan pada langkah sebelumnya untuk membuat buku besar. Klien sebelumnya hanya digunakan untuk menjalankan operasi API manajemen yang tercantum dalam[Referensi API QLDB Amazon](api-reference.md). Kami merekomendasikan penggunaan `PooledQldbDriver` kecuali Anda perlu menerapkan kumpulan sesi khusus dengan`QldbDriver`. Ukuran kolam default untuk `PooledQldbDriver` adalah [jumlah maksimum koneksi HTTP terbuka](https://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/ClientConfiguration.html#getMaxConnections--) yang memungkinkan klien sesi. Pertama, buat `PooledQldbDriver` objek. Anda harus menentukan nama buku besar saat Anda membuat driver ini. Kemudian, Anda dapat menggunakan `execute` metode driver ini untuk menjalankan pernyataan PartiQL. Atau, Anda dapat membuat sesi secara manual dari objek driver yang dikumpulkan ini dan menggunakan metode sesi. `execute` Sesi mewakili koneksi tunggal dengan buku besar. Secara opsional, Anda dapat menentukan jumlah maksimum percobaan ulang untuk pengecualian transaksi. `execute`Metode ini secara otomatis mencoba kembali konflik kontrol konkurensi optimis (OCC) dan pengecualian sementara umum lainnya hingga batas yang dapat dikonfigurasi ini. Nilai default-nya adalah `4`. Jika transaksi masih gagal setelah batas tercapai, maka pengemudi melempar pengecualian. Untuk mempelajari selengkapnya, lihat [Memahami kebijakan coba lagi dengan pengemudi di Amazon QLDB](driver-retry-policy.md). ------ 1. Kompilasi dan jalankan `ConnectToLedger.java` program untuk menguji konektivitas sesi data Anda ke `vehicle-registration` buku besar. **Mengesampingkan Wilayah AWS** Aplikasi sampel terhubung ke QLDB dalam Wilayah AWS default Anda, yang dapat Anda atur seperti yang dijelaskan dalam langkah prasyarat. [Menyetel AWS kredensial default dan Wilayah](getting-started.java.md#getting-started.java.credentials) Anda juga dapat mengubah Wilayah dengan memodifikasi properti pembuat klien sesi QLDB. ------ #### [ 2.x ] Contoh kode berikut membuat instance objek baru`QldbSessionClientBuilder`. ``` import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.qldbsession.QldbSessionClientBuilder; // This client builder will default to US East (Ohio) QldbSessionClientBuilder builder = QldbSessionClient.builder() .region(Region.US_EAST_2); ``` Anda dapat menggunakan `region` metode ini untuk menjalankan kode Anda terhadap QLDB di Wilayah mana pun yang tersedia. Untuk daftar lengkapnya, lihat [titik akhir QLDB Amazon](https://docs.aws.amazon.com/general/latest/gr/qldb.html) dan kuota di. *Referensi Umum AWS* ------ #### [ 1.x ] Contoh kode berikut membuat instance objek baru`AmazonQLDBSessionClientBuilder`. ``` import com.amazonaws.regions.Regions; import com.amazonaws.services.qldbsession.AmazonQLDBSessionClientBuilder; // This client builder will default to US East (Ohio) AmazonQLDBSessionClientBuilder builder = AmazonQLDBSessionClientBuilder.standard() .withRegion(Regions.US_EAST_2); ``` Anda dapat menggunakan `withRegion` metode ini untuk menjalankan kode Anda terhadap QLDB di Wilayah mana pun yang tersedia. Untuk daftar lengkapnya, lihat [titik akhir QLDB Amazon](https://docs.aws.amazon.com/general/latest/gr/qldb.html) dan kuota di. *Referensi Umum AWS* ------ Untuk membuat tabel di `vehicle-registration` buku besar, lanjutkan ke[Langkah 3: Buat tabel, indeks, dan data sampel](getting-started.java.step-3.md). # Langkah 3: Buat tabel, indeks, dan data sampel **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Saat buku besar QLDB Amazon Anda aktif dan menerima koneksi, Anda dapat mulai membuat tabel untuk data tentang kendaraan, pemiliknya, dan informasi pendaftarannya. Setelah membuat tabel dan indeks, Anda dapat memuatnya dengan data. Pada langkah ini, Anda membuat empat tabel di `vehicle-registration` buku besar: + `VehicleRegistration` + `Vehicle` + `Person` + `DriversLicense` Anda juga membuat indeks berikut. **** | Nama tabel | Bidang | | --- | --- | | VehicleRegistration | VIN | | VehicleRegistration | LicensePlateNumber | | Vehicle | VIN | | Person | GovId | | DriversLicense | LicenseNumber | | DriversLicense | PersonId | Saat memasukkan data sampel, Anda terlebih dahulu memasukkan dokumen ke dalam `Person` tabel. Kemudian, Anda menggunakan sistem yang ditetapkan `id` dari setiap `Person` dokumen untuk mengisi bidang yang sesuai di dokumen yang sesuai`VehicleRegistration`. `DriversLicense` **Tip** Sebagai praktik terbaik, gunakan sistem dokumen yang ditugaskan `id` sebagai kunci asing. Meskipun Anda dapat menentukan bidang yang dimaksudkan untuk menjadi pengidentifikasi unik (misalnya, VIN kendaraan), pengidentifikasi unik sebenarnya dari dokumen adalah miliknya. `id` Bidang ini disertakan dalam metadata dokumen, yang dapat Anda kueri dalam tampilan *komited (tampilan* tabel yang ditentukan sistem). Untuk informasi selengkapnya tentang tampilan di QLDB, lihat. [Konsep inti](ledger-structure.md) Untuk mempelajari lebih lanjut tentang metadata, lihat. [Meminta metadata dokumen](working.metadata.md) **Untuk mengatur data sampel** 1. Tinjau `.java` file-file berikut. Kelas model ini mewakili dokumen yang Anda simpan dalam `vehicle-registration` tabel. Mereka dapat diserialkan ke dan dari format Amazon Ion. **catatan** [Dokumen QLDB Amazon](ql-reference.docs.md)disimpan dalam format Ion, yang merupakan superset dari JSON. Jadi, Anda dapat menggunakan perpustakaan FasterXMLJackson untuk memodelkan data di JSON. 1. `DriversLicense.java` ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.annotation.JsonDeserialize; import com.fasterxml.jackson.databind.annotation.JsonSerialize; import software.amazon.qldb.tutorial.model.streams.RevisionData; import java.time.LocalDate; /** * Represents a driver's license, serializable to (and from) Ion. */ public final class DriversLicense implements RevisionData { private final String personId; private final String licenseNumber; private final String licenseType; @JsonSerialize(using = IonLocalDateSerializer.class) @JsonDeserialize(using = IonLocalDateDeserializer.class) private final LocalDate validFromDate; @JsonSerialize(using = IonLocalDateSerializer.class) @JsonDeserialize(using = IonLocalDateDeserializer.class) private final LocalDate validToDate; @JsonCreator public DriversLicense(@JsonProperty("PersonId") final String personId, @JsonProperty("LicenseNumber") final String licenseNumber, @JsonProperty("LicenseType") final String licenseType, @JsonProperty("ValidFromDate") final LocalDate validFromDate, @JsonProperty("ValidToDate") final LocalDate validToDate) { this.personId = personId; this.licenseNumber = licenseNumber; this.licenseType = licenseType; this.validFromDate = validFromDate; this.validToDate = validToDate; } @JsonProperty("PersonId") public String getPersonId() { return personId; } @JsonProperty("LicenseNumber") public String getLicenseNumber() { return licenseNumber; } @JsonProperty("LicenseType") public String getLicenseType() { return licenseType; } @JsonProperty("ValidFromDate") public LocalDate getValidFromDate() { return validFromDate; } @JsonProperty("ValidToDate") public LocalDate getValidToDate() { return validToDate; } @Override public String toString() { return "DriversLicense{" + "personId='" + personId + '\'' + ", licenseNumber='" + licenseNumber + '\'' + ", licenseType='" + licenseType + '\'' + ", validFromDate=" + validFromDate + ", validToDate=" + validToDate + '}'; } } ``` 1. `Person.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import java.time.LocalDate; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.annotation.JsonDeserialize; import com.fasterxml.jackson.databind.annotation.JsonSerialize; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.Constants; import software.amazon.qldb.tutorial.model.streams.RevisionData; /** * Represents a person, serializable to (and from) Ion. */ public final class Person implements RevisionData { private final String firstName; private final String lastName; @JsonSerialize(using = IonLocalDateSerializer.class) @JsonDeserialize(using = IonLocalDateDeserializer.class) private final LocalDate dob; private final String govId; private final String govIdType; private final String address; @JsonCreator public Person(@JsonProperty("FirstName") final String firstName, @JsonProperty("LastName") final String lastName, @JsonProperty("DOB") final LocalDate dob, @JsonProperty("GovId") final String govId, @JsonProperty("GovIdType") final String govIdType, @JsonProperty("Address") final String address) { this.firstName = firstName; this.lastName = lastName; this.dob = dob; this.govId = govId; this.govIdType = govIdType; this.address = address; } @JsonProperty("Address") public String getAddress() { return address; } @JsonProperty("DOB") public LocalDate getDob() { return dob; } @JsonProperty("FirstName") public String getFirstName() { return firstName; } @JsonProperty("LastName") public String getLastName() { return lastName; } @JsonProperty("GovId") public String getGovId() { return govId; } @JsonProperty("GovIdType") public String getGovIdType() { return govIdType; } /** * This returns the unique document ID given a specific government ID. * * @param txn * A transaction executor object. * @param govId * The government ID of a driver. * @return the unique document ID. */ public static String getDocumentIdByGovId(final TransactionExecutor txn, final String govId) { return SampleData.getDocumentId(txn, Constants.PERSON_TABLE_NAME, "GovId", govId); } @Override public String toString() { return "Person{" + "firstName='" + firstName + '\'' + ", lastName='" + lastName + '\'' + ", dob=" + dob + ", govId='" + govId + '\'' + ", govIdType='" + govIdType + '\'' + ", address='" + address + '\'' + '}'; } } ``` 1. `VehicleRegistration.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.annotation.JsonDeserialize; import com.fasterxml.jackson.databind.annotation.JsonSerialize; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.Constants; import software.amazon.qldb.tutorial.model.streams.RevisionData; import java.math.BigDecimal; import java.time.LocalDate; /** * Represents a vehicle registration, serializable to (and from) Ion. */ public final class VehicleRegistration implements RevisionData { private final String vin; private final String licensePlateNumber; private final String state; private final String city; private final BigDecimal pendingPenaltyTicketAmount; private final LocalDate validFromDate; private final LocalDate validToDate; private final Owners owners; @JsonCreator public VehicleRegistration(@JsonProperty("VIN") final String vin, @JsonProperty("LicensePlateNumber") final String licensePlateNumber, @JsonProperty("State") final String state, @JsonProperty("City") final String city, @JsonProperty("PendingPenaltyTicketAmount") final BigDecimal pendingPenaltyTicketAmount, @JsonProperty("ValidFromDate") final LocalDate validFromDate, @JsonProperty("ValidToDate") final LocalDate validToDate, @JsonProperty("Owners") final Owners owners) { this.vin = vin; this.licensePlateNumber = licensePlateNumber; this.state = state; this.city = city; this.pendingPenaltyTicketAmount = pendingPenaltyTicketAmount; this.validFromDate = validFromDate; this.validToDate = validToDate; this.owners = owners; } @JsonProperty("City") public String getCity() { return city; } @JsonProperty("LicensePlateNumber") public String getLicensePlateNumber() { return licensePlateNumber; } @JsonProperty("Owners") public Owners getOwners() { return owners; } @JsonProperty("PendingPenaltyTicketAmount") public BigDecimal getPendingPenaltyTicketAmount() { return pendingPenaltyTicketAmount; } @JsonProperty("State") public String getState() { return state; } @JsonProperty("ValidFromDate") @JsonSerialize(using = IonLocalDateSerializer.class) @JsonDeserialize(using = IonLocalDateDeserializer.class) public LocalDate getValidFromDate() { return validFromDate; } @JsonProperty("ValidToDate") @JsonSerialize(using = IonLocalDateSerializer.class) @JsonDeserialize(using = IonLocalDateDeserializer.class) public LocalDate getValidToDate() { return validToDate; } @JsonProperty("VIN") public String getVin() { return vin; } /** * Returns the unique document ID of a vehicle given a specific VIN. * * @param txn * A transaction executor object. * @param vin * The VIN of a vehicle. * @return the unique document ID of the specified vehicle. */ public static String getDocumentIdByVin(final TransactionExecutor txn, final String vin) { return SampleData.getDocumentId(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, "VIN", vin); } @Override public String toString() { return "VehicleRegistration{" + "vin='" + vin + '\'' + ", licensePlateNumber='" + licensePlateNumber + '\'' + ", state='" + state + '\'' + ", city='" + city + '\'' + ", pendingPenaltyTicketAmount=" + pendingPenaltyTicketAmount + ", validFromDate=" + validFromDate + ", validToDate=" + validToDate + ", owners=" + owners + '}'; } } ``` 1. `Vehicle.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import software.amazon.qldb.tutorial.model.streams.RevisionData; /** * Represents a vehicle, serializable to (and from) Ion. */ public final class Vehicle implements RevisionData { private final String vin; private final String type; private final int year; private final String make; private final String model; private final String color; @JsonCreator public Vehicle(@JsonProperty("VIN") final String vin, @JsonProperty("Type") final String type, @JsonProperty("Year") final int year, @JsonProperty("Make") final String make, @JsonProperty("Model") final String model, @JsonProperty("Color") final String color) { this.vin = vin; this.type = type; this.year = year; this.make = make; this.model = model; this.color = color; } @JsonProperty("Color") public String getColor() { return color; } @JsonProperty("Make") public String getMake() { return make; } @JsonProperty("Model") public String getModel() { return model; } @JsonProperty("Type") public String getType() { return type; } @JsonProperty("VIN") public String getVin() { return vin; } @JsonProperty("Year") public int getYear() { return year; } @Override public String toString() { return "Vehicle{" + "vin='" + vin + '\'' + ", type='" + type + '\'' + ", year=" + year + ", make='" + make + '\'' + ", model='" + model + '\'' + ", color='" + color + '\'' + '}'; } } ``` 1. `Owner.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.fasterxml.jackson.annotation.JsonProperty; /** * Represents a vehicle owner, serializable to (and from) Ion. */ public final class Owner { private final String personId; public Owner(@JsonProperty("PersonId") final String personId) { this.personId = personId; } @JsonProperty("PersonId") public String getPersonId() { return personId; } @Override public String toString() { return "Owner{" + "personId='" + personId + '\'' + '}'; } } ``` 1. `Owners.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.fasterxml.jackson.annotation.JsonProperty; import java.util.List; /** * Represents a set of owners for a given vehicle, serializable to (and from) Ion. */ public final class Owners { private final Owner primaryOwner; private final List secondaryOwners; public Owners(@JsonProperty("PrimaryOwner") final Owner primaryOwner, @JsonProperty("SecondaryOwners") final List secondaryOwners) { this.primaryOwner = primaryOwner; this.secondaryOwners = secondaryOwners; } @JsonProperty("PrimaryOwner") public Owner getPrimaryOwner() { return primaryOwner; } @JsonProperty("SecondaryOwners") public List getSecondaryOwners() { return secondaryOwners; } @Override public String toString() { return "Owners{" + "primaryOwner=" + primaryOwner + ", secondaryOwners=" + secondaryOwners + '}'; } } ``` 1. `DmlResultDocument.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; /** * Contains information about an individual document inserted or modified * as a result of DML. */ public class DmlResultDocument { private String documentId; @JsonCreator public DmlResultDocument(@JsonProperty("documentId") final String documentId) { this.documentId = documentId; } public String getDocumentId() { return documentId; } @Override public String toString() { return "DmlResultDocument{" + "documentId='" + documentId + '\'' + '}'; } } ``` 1. `RevisionData.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model.streams; /** * Allows modeling the content of all revisions as a generic revision data. Used * in the {@link Revision} and extended by domain models in {@link * software.amazon.qldb.tutorial.model} to make it easier to write the {@link * Revision.RevisionDataDeserializer} that must deserialize the {@link * Revision#data} from different domain models. */ public interface RevisionData { } ``` 1. `RevisionMetadata.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.amazon.ion.IonInt; import com.amazon.ion.IonString; import com.amazon.ion.IonStruct; import com.amazon.ion.IonTimestamp; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.annotation.JsonSerialize; import com.fasterxml.jackson.dataformat.ion.IonTimestampSerializers; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.util.Date; import java.util.Objects; /** * Represents the metadata field of a QLDB Document */ public class RevisionMetadata { private static final Logger log = LoggerFactory.getLogger(RevisionMetadata.class); private final String id; private final long version; @JsonSerialize(using = IonTimestampSerializers.IonTimestampJavaDateSerializer.class) private final Date txTime; private final String txId; @JsonCreator public RevisionMetadata(@JsonProperty("id") final String id, @JsonProperty("version") final long version, @JsonProperty("txTime") final Date txTime, @JsonProperty("txId") final String txId) { this.id = id; this.version = version; this.txTime = txTime; this.txId = txId; } /** * Gets the unique ID of a QLDB document. * * @return the document ID. */ public String getId() { return id; } /** * Gets the version number of the document in the document's modification history. * @return the version number. */ public long getVersion() { return version; } /** * Gets the time during which the document was modified. * * @return the transaction time. */ public Date getTxTime() { return txTime; } /** * Gets the transaction ID associated with this document. * * @return the transaction ID. */ public String getTxId() { return txId; } public static RevisionMetadata fromIon(final IonStruct ionStruct) { if (ionStruct == null) { throw new IllegalArgumentException("Metadata cannot be null"); } try { IonString id = (IonString) ionStruct.get("id"); IonInt version = (IonInt) ionStruct.get("version"); IonTimestamp txTime = (IonTimestamp) ionStruct.get("txTime"); IonString txId = (IonString) ionStruct.get("txId"); if (id == null || version == null || txTime == null || txId == null) { throw new IllegalArgumentException("Document is missing required fields"); } return new RevisionMetadata(id.stringValue(), version.longValue(), new Date(txTime.getMillis()), txId.stringValue()); } catch (ClassCastException e) { log.error("Failed to parse ion document"); throw new IllegalArgumentException("Document members are not of the correct type", e); } } /** * Converts a {@link RevisionMetadata} object to a string. * * @return the string representation of the {@link QldbRevision} object. */ @Override public String toString() { return "Metadata{" + "id='" + id + '\'' + ", version=" + version + ", txTime=" + txTime + ", txId='" + txId + '\'' + '}'; } /** * Check whether two {@link RevisionMetadata} objects are equivalent. * * @return {@code true} if the two objects are equal, {@code false} otherwise. */ @Override public boolean equals(Object o) { if (this == o) { return true; } if (o == null || getClass() != o.getClass()) { return false; } RevisionMetadata metadata = (RevisionMetadata) o; return version == metadata.version && id.equals(metadata.id) && txTime.equals(metadata.txTime) && txId.equals(metadata.txId); } /** * Generate a hash code for the {@link RevisionMetadata} object. * * @return the hash code. */ @Override public int hashCode() { // CHECKSTYLE:OFF - Disabling as we are generating a hashCode of multiple properties. return Objects.hash(id, version, txTime, txId); // CHECKSTYLE:ON } } ``` 1. `QldbRevision.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.amazon.ion.IonBlob; import com.amazon.ion.IonStruct; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.tutorial.Constants; import software.amazon.qldb.tutorial.Verifier; import java.io.IOException; import java.util.Arrays; import java.util.Objects; /** * Represents a QldbRevision including both user data and metadata. */ public final class QldbRevision { private static final Logger log = LoggerFactory.getLogger(QldbRevision.class); private final BlockAddress blockAddress; private final RevisionMetadata metadata; private final byte[] hash; private final byte[] dataHash; private final IonStruct data; @JsonCreator public QldbRevision(@JsonProperty("blockAddress") final BlockAddress blockAddress, @JsonProperty("metadata") final RevisionMetadata metadata, @JsonProperty("hash") final byte[] hash, @JsonProperty("dataHash") final byte[] dataHash, @JsonProperty("data") final IonStruct data) { this.blockAddress = blockAddress; this.metadata = metadata; this.hash = hash; this.dataHash = dataHash; this.data = data; } /** * Gets the unique ID of a QLDB document. * * @return the {@link BlockAddress} object. */ public BlockAddress getBlockAddress() { return blockAddress; } /** * Gets the metadata of the revision. * * @return the {@link RevisionMetadata} object. */ public RevisionMetadata getMetadata() { return metadata; } /** * Gets the SHA-256 hash value of the revision. * This is equivalent to the hash of the revision metadata and data. * * @return the byte array representing the hash. */ public byte[] getHash() { return hash; } /** * Gets the SHA-256 hash value of the data portion of the revision. * This is only present if the revision is redacted. * * @return the byte array representing the hash. */ public byte[] getDataHash() { return dataHash; } /** * Gets the revision data. * * @return the revision data. */ public IonStruct getData() { return data; } /** * Returns true if the revision has been redacted. * @return a boolean value representing the redaction status * of this revision. */ public Boolean isRedacted() { return dataHash != null; } /** * Constructs a new {@link QldbRevision} from an {@link IonStruct}. * * The specified {@link IonStruct} must include the following fields * * - blockAddress -- a {@link BlockAddress}, * - metadata -- a {@link RevisionMetadata}, * - hash -- the revision's hash calculated by QLDB, * - dataHash -- the user data's hash calculated by QLDB (only present if revision is redacted), * - data -- an {@link IonStruct} containing user data in the document. * * If any of these fields are missing or are malformed, then throws {@link IllegalArgumentException}. * * If the document hash calculated from the members of the specified {@link IonStruct} does not match * the hash member of the {@link IonStruct} then throws {@link IllegalArgumentException}. * * @param ionStruct * The {@link IonStruct} that contains a {@link QldbRevision} object. * @return the converted {@link QldbRevision} object. * @throws IOException if failed to parse parameter {@link IonStruct}. */ public static QldbRevision fromIon(final IonStruct ionStruct) throws IOException { try { BlockAddress blockAddress = Constants.MAPPER.readValue(ionStruct.get("blockAddress"), BlockAddress.class); IonBlob revisionHash = (IonBlob) ionStruct.get("hash"); IonStruct metadataStruct = (IonStruct) ionStruct.get("metadata"); IonStruct data = ionStruct.get("data") == null || ionStruct.get("data").isNullValue() ? null : (IonStruct) ionStruct.get("data"); IonBlob dataHash = ionStruct.get("dataHash") == null || ionStruct.get("dataHash").isNullValue() ? null : (IonBlob) ionStruct.get("dataHash"); if (revisionHash == null || metadataStruct == null) { throw new IllegalArgumentException("Document is missing required fields"); } byte[] dataHashBytes = dataHash != null ? dataHash.getBytes() : QldbIonUtils.hashIonValue(data); verifyRevisionHash(metadataStruct, dataHashBytes, revisionHash.getBytes()); RevisionMetadata metadata = RevisionMetadata.fromIon(metadataStruct); return new QldbRevision( blockAddress, metadata, revisionHash.getBytes(), dataHash != null ? dataHash.getBytes() : null, data ); } catch (ClassCastException e) { log.error("Failed to parse ion document"); throw new IllegalArgumentException("Document members are not of the correct type", e); } } /** * Converts a {@link QldbRevision} object to string. * * @return the string representation of the {@link QldbRevision} object. */ @Override public String toString() { return "QldbRevision{" + "blockAddress=" + blockAddress + ", metadata=" + metadata + ", hash=" + Arrays.toString(hash) + ", dataHash=" + Arrays.toString(dataHash) + ", data=" + data + '}'; } /** * Check whether two {@link QldbRevision} objects are equivalent. * * @return {@code true} if the two objects are equal, {@code false} otherwise. */ @Override public boolean equals(final Object o) { if (this == o) { return true; } if (!(o instanceof QldbRevision)) { return false; } final QldbRevision that = (QldbRevision) o; return Objects.equals(getBlockAddress(), that.getBlockAddress()) && Objects.equals(getMetadata(), that.getMetadata()) && Arrays.equals(getHash(), that.getHash()) && Arrays.equals(getDataHash(), that.getDataHash()) && Objects.equals(getData(), that.getData()); } /** * Create a hash code for the {@link QldbRevision} object. * * @return the hash code. */ @Override public int hashCode() { // CHECKSTYLE:OFF - Disabling as we are generating a hashCode of multiple properties. int result = Objects.hash(blockAddress, metadata, data); // CHECKSTYLE:ON result = 31 * result + Arrays.hashCode(hash); return result; } /** * Throws an IllegalArgumentException if the hash of the revision data and metadata * does not match the hash provided by QLDB with the revision. */ public void verifyRevisionHash() { // Certain internal-only system revisions only contain a hash which cannot be // further computed. However, these system hashes still participate to validate // the journal block. User revisions will always contain values for all fields // and can therefore have their hash computed. if (blockAddress == null && metadata == null && data == null && dataHash == null) { return; } try { IonStruct metadataIon = (IonStruct) Constants.MAPPER.writeValueAsIonValue(metadata); byte[] dataHashBytes = isRedacted() ? dataHash : QldbIonUtils.hashIonValue(data); verifyRevisionHash(metadataIon, dataHashBytes, hash); } catch (IOException e) { throw new IllegalArgumentException("Could not encode revision metadata to ion.", e); } } private static void verifyRevisionHash(IonStruct metadata, byte[] dataHash, byte[] expectedHash) { byte[] metadataHash = QldbIonUtils.hashIonValue(metadata); byte[] candidateHash = Verifier.dot(metadataHash, dataHash); if (!Arrays.equals(candidateHash, expectedHash)) { throw new IllegalArgumentException("Hash entry of QLDB revision and computed hash " + "of QLDB revision do not match"); } } } ``` 1. `IonLocalDateDeserializer.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.amazon.ion.Timestamp; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.JsonDeserializer; import java.io.IOException; import java.time.LocalDate; /** * Deserializes [java.time.LocalDate] from Ion. */ public class IonLocalDateDeserializer extends JsonDeserializer { @Override public LocalDate deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException { return timestampToLocalDate((Timestamp) jp.getEmbeddedObject()); } private LocalDate timestampToLocalDate(Timestamp timestamp) { return LocalDate.of(timestamp.getYear(), timestamp.getMonth(), timestamp.getDay()); } } ``` 1. `IonLocalDateSerializer.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.amazon.ion.Timestamp; import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.databind.SerializerProvider; import com.fasterxml.jackson.databind.ser.std.StdScalarSerializer; import com.fasterxml.jackson.dataformat.ion.IonGenerator; import java.io.IOException; import java.time.LocalDate; /** * Serializes [java.time.LocalDate] to Ion. */ public class IonLocalDateSerializer extends StdScalarSerializer { public IonLocalDateSerializer() { super(LocalDate.class); } @Override public void serialize(LocalDate date, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException { Timestamp timestamp = Timestamp.forDay(date.getYear(), date.getMonthValue(), date.getDayOfMonth()); ((IonGenerator) jsonGenerator).writeValue(timestamp); } } ``` 1. Tinjau file berikut (`SampleData.java`), yang mewakili data sampel yang Anda masukkan ke dalam `vehicle-registration` tabel. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.amazon.ion.IonString; import com.amazon.ion.IonStruct; import com.amazon.ion.IonValue; import java.io.IOException; import java.math.BigDecimal; import java.text.ParseException; import java.time.LocalDate; import java.time.format.DateTimeFormatter; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.ConnectToLedger; import software.amazon.qldb.tutorial.Constants; import software.amazon.qldb.tutorial.qldb.DmlResultDocument; import software.amazon.qldb.tutorial.qldb.QldbRevision; /** * Sample domain objects for use throughout this tutorial. */ public final class SampleData { public static final DateTimeFormatter DATE_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd"); public static final List REGISTRATIONS = Collections.unmodifiableList(Arrays.asList( new VehicleRegistration("1N4AL11D75C109151", "LEWISR261LL", "WA", "Seattle", BigDecimal.valueOf(90.25), convertToLocalDate("2017-08-21"), convertToLocalDate("2020-05-11"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("KM8SRDHF6EU074761", "CA762X", "WA", "Kent", BigDecimal.valueOf(130.75), convertToLocalDate("2017-09-14"), convertToLocalDate("2020-06-25"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("3HGGK5G53FM761765", "CD820Z", "WA", "Everett", BigDecimal.valueOf(442.30), convertToLocalDate("2011-03-17"), convertToLocalDate("2021-03-24"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("1HVBBAANXWH544237", "LS477D", "WA", "Tacoma", BigDecimal.valueOf(42.20), convertToLocalDate("2011-10-26"), convertToLocalDate("2023-09-25"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("1C4RJFAG0FC625797", "TH393F", "WA", "Olympia", BigDecimal.valueOf(30.45), convertToLocalDate("2013-09-02"), convertToLocalDate("2024-03-19"), new Owners(new Owner(null), Collections.emptyList())) )); public static final List VEHICLES = Collections.unmodifiableList(Arrays.asList( new Vehicle("1N4AL11D75C109151", "Sedan", 2011, "Audi", "A5", "Silver"), new Vehicle("KM8SRDHF6EU074761", "Sedan", 2015, "Tesla", "Model S", "Blue"), new Vehicle("3HGGK5G53FM761765", "Motorcycle", 2011, "Ducati", "Monster 1200", "Yellow"), new Vehicle("1HVBBAANXWH544237", "Semi", 2009, "Ford", "F 150", "Black"), new Vehicle("1C4RJFAG0FC625797", "Sedan", 2019, "Mercedes", "CLK 350", "White") )); public static final List PEOPLE = Collections.unmodifiableList(Arrays.asList( new Person("Raul", "Lewis", convertToLocalDate("1963-08-19"), "LEWISR261LL", "Driver License", "1719 University Street, Seattle, WA, 98109"), new Person("Brent", "Logan", convertToLocalDate("1967-07-03"), "LOGANB486CG", "Driver License", "43 Stockert Hollow Road, Everett, WA, 98203"), new Person("Alexis", "Pena", convertToLocalDate("1974-02-10"), "744 849 301", "SSN", "4058 Melrose Street, Spokane Valley, WA, 99206"), new Person("Melvin", "Parker", convertToLocalDate("1976-05-22"), "P626-168-229-765", "Passport", "4362 Ryder Avenue, Seattle, WA, 98101"), new Person("Salvatore", "Spencer", convertToLocalDate("1997-11-15"), "S152-780-97-415-0", "Passport", "4450 Honeysuckle Lane, Seattle, WA, 98101") )); public static final List LICENSES = Collections.unmodifiableList(Arrays.asList( new DriversLicense(null, "LEWISR261LL", "Learner", convertToLocalDate("2016-12-20"), convertToLocalDate("2020-11-15")), new DriversLicense(null, "LOGANB486CG", "Probationary", convertToLocalDate("2016-04-06"), convertToLocalDate("2020-11-15")), new DriversLicense(null, "744 849 301", "Full", convertToLocalDate("2017-12-06"), convertToLocalDate("2022-10-15")), new DriversLicense(null, "P626-168-229-765", "Learner", convertToLocalDate("2017-08-16"), convertToLocalDate("2021-11-15")), new DriversLicense(null, "S152-780-97-415-0", "Probationary", convertToLocalDate("2015-08-15"), convertToLocalDate("2021-08-21")) )); private SampleData() { } /** * Converts a date string with the format 'yyyy-MM-dd' into a {@link java.util.Date} object. * * @param date * The date string to convert. * @return {@link java.time.LocalDate} or null if there is a {@link ParseException} */ public static synchronized LocalDate convertToLocalDate(String date) { return LocalDate.parse(date, DATE_TIME_FORMAT); } /** * Convert the result set into a list of IonValues. * * @param result * The result set to convert. * @return a list of IonValues. */ public static List toIonValues(Result result) { final List valueList = new ArrayList<>(); result.iterator().forEachRemaining(valueList::add); return valueList; } /** * Get the document ID of a particular document. * * @param txn * A transaction executor object. * @param tableName * Name of the table containing the document. * @param identifier * The identifier used to narrow down the search. * @param value * Value of the identifier. * @return the list of document IDs in the result set. */ public static String getDocumentId(final TransactionExecutor txn, final String tableName, final String identifier, final String value) { try { final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(value)); final String query = String.format("SELECT metadata.id FROM _ql_committed_%s AS p WHERE p.data.%s = ?", tableName, identifier); Result result = txn.execute(query, parameters); if (result.isEmpty()) { throw new IllegalStateException("Unable to retrieve document ID using " + value); } return getStringValueOfStructField((IonStruct) result.iterator().next(), "id"); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Get the document by ID. * * @param tableName * Name of the table to insert documents into. * @param documentId * The unique ID of a document in the Person table. * @return a {@link QldbRevision} object. * @throws IllegalStateException if failed to convert parameter into {@link IonValue}. */ public static QldbRevision getDocumentById(String tableName, String documentId) { try { final IonValue ionValue = Constants.MAPPER.writeValueAsIonValue(documentId); Result result = ConnectToLedger.getDriver().execute(txn -> { return txn.execute("SELECT c.* FROM _ql_committed_" + tableName + " AS c BY docId " + "WHERE docId = ?", ionValue); }); if (result.isEmpty()) { throw new IllegalStateException("Unable to retrieve document by id " + documentId + " in table " + tableName); } return Constants.MAPPER.readValue(result.iterator().next(), QldbRevision.class); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Return a list of modified document IDs as strings from a DML {@link Result}. * * @param result * The result set from a DML operation. * @return the list of document IDs modified by the operation. */ public static List getDocumentIdsFromDmlResult(final Result result) { final List strings = new ArrayList<>(); result.iterator().forEachRemaining(row -> strings.add(getDocumentIdFromDmlResultDocument(row))); return strings; } /** * Convert the given DML result row's document ID to string. * * @param dmlResultDocument * The {@link IonValue} representing the results of a DML operation. * @return a string of document ID. */ public static String getDocumentIdFromDmlResultDocument(final IonValue dmlResultDocument) { try { DmlResultDocument result = Constants.MAPPER.readValue(dmlResultDocument, DmlResultDocument.class); return result.getDocumentId(); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Get the String value of a given {@link IonStruct} field name. * @param struct the {@link IonStruct} from which to get the value. * @param fieldName the name of the field from which to get the value. * @return the String value of the field within the given {@link IonStruct}. */ public static String getStringValueOfStructField(final IonStruct struct, final String fieldName) { return ((IonString) struct.get(fieldName)).stringValue(); } /** * Return a copy of the given driver's license with updated person Id. * * @param oldLicense * The old driver's license to update. * @param personId * The PersonId of the driver. * @return the updated {@link DriversLicense}. */ public static DriversLicense updatePersonIdDriversLicense(final DriversLicense oldLicense, final String personId) { return new DriversLicense(personId, oldLicense.getLicenseNumber(), oldLicense.getLicenseType(), oldLicense.getValidFromDate(), oldLicense.getValidToDate()); } /** * Return a copy of the given vehicle registration with updated person Id. * * @param oldRegistration * The old vehicle registration to update. * @param personId * The PersonId of the driver. * @return the updated {@link VehicleRegistration}. */ public static VehicleRegistration updateOwnerVehicleRegistration(final VehicleRegistration oldRegistration, final String personId) { return new VehicleRegistration(oldRegistration.getVin(), oldRegistration.getLicensePlateNumber(), oldRegistration.getState(), oldRegistration.getCity(), oldRegistration.getPendingPenaltyTicketAmount(), oldRegistration.getValidFromDate(), oldRegistration.getValidToDate(), new Owners(new Owner(personId), Collections.emptyList())); } } ``` ------ #### [ 1.x ] **penting** Untuk paket Amazon Ion, Anda harus menggunakan namespace `com.amazon.ion` di aplikasi Anda. AWS SDK untuk Java Tergantung pada paket Ion lain di bawah namespace`software.amazon.ion`, tetapi ini adalah paket lama yang tidak kompatibel dengan driver QLDB. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.model; import com.amazon.ion.IonString; import com.amazon.ion.IonStruct; import com.amazon.ion.IonValue; import software.amazon.qldb.QldbSession; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.Constants; import software.amazon.qldb.tutorial.qldb.DmlResultDocument; import software.amazon.qldb.tutorial.qldb.QldbRevision; import java.io.IOException; import java.math.BigDecimal; import java.text.ParseException; import java.time.LocalDate; import java.time.format.DateTimeFormatter; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; /** * Sample domain objects for use throughout this tutorial. */ public final class SampleData { public static final DateTimeFormatter DATE_TIME_FORMAT = DateTimeFormatter.ofPattern("yyyy-MM-dd"); public static final List REGISTRATIONS = Collections.unmodifiableList(Arrays.asList( new VehicleRegistration("1N4AL11D75C109151", "LEWISR261LL", "WA", "Seattle", BigDecimal.valueOf(90.25), convertToLocalDate("2017-08-21"), convertToLocalDate("2020-05-11"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("KM8SRDHF6EU074761", "CA762X", "WA", "Kent", BigDecimal.valueOf(130.75), convertToLocalDate("2017-09-14"), convertToLocalDate("2020-06-25"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("3HGGK5G53FM761765", "CD820Z", "WA", "Everett", BigDecimal.valueOf(442.30), convertToLocalDate("2011-03-17"), convertToLocalDate("2021-03-24"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("1HVBBAANXWH544237", "LS477D", "WA", "Tacoma", BigDecimal.valueOf(42.20), convertToLocalDate("2011-10-26"), convertToLocalDate("2023-09-25"), new Owners(new Owner(null), Collections.emptyList())), new VehicleRegistration("1C4RJFAG0FC625797", "TH393F", "WA", "Olympia", BigDecimal.valueOf(30.45), convertToLocalDate("2013-09-02"), convertToLocalDate("2024-03-19"), new Owners(new Owner(null), Collections.emptyList())) )); public static final List VEHICLES = Collections.unmodifiableList(Arrays.asList( new Vehicle("1N4AL11D75C109151", "Sedan", 2011, "Audi", "A5", "Silver"), new Vehicle("KM8SRDHF6EU074761", "Sedan", 2015, "Tesla", "Model S", "Blue"), new Vehicle("3HGGK5G53FM761765", "Motorcycle", 2011, "Ducati", "Monster 1200", "Yellow"), new Vehicle("1HVBBAANXWH544237", "Semi", 2009, "Ford", "F 150", "Black"), new Vehicle("1C4RJFAG0FC625797", "Sedan", 2019, "Mercedes", "CLK 350", "White") )); public static final List PEOPLE = Collections.unmodifiableList(Arrays.asList( new Person("Raul", "Lewis", convertToLocalDate("1963-08-19"), "LEWISR261LL", "Driver License", "1719 University Street, Seattle, WA, 98109"), new Person("Brent", "Logan", convertToLocalDate("1967-07-03"), "LOGANB486CG", "Driver License", "43 Stockert Hollow Road, Everett, WA, 98203"), new Person("Alexis", "Pena", convertToLocalDate("1974-02-10"), "744 849 301", "SSN", "4058 Melrose Street, Spokane Valley, WA, 99206"), new Person("Melvin", "Parker", convertToLocalDate("1976-05-22"), "P626-168-229-765", "Passport", "4362 Ryder Avenue, Seattle, WA, 98101"), new Person("Salvatore", "Spencer", convertToLocalDate("1997-11-15"), "S152-780-97-415-0", "Passport", "4450 Honeysuckle Lane, Seattle, WA, 98101") )); public static final List LICENSES = Collections.unmodifiableList(Arrays.asList( new DriversLicense(null, "LEWISR261LL", "Learner", convertToLocalDate("2016-12-20"), convertToLocalDate("2020-11-15")), new DriversLicense(null, "LOGANB486CG", "Probationary", convertToLocalDate("2016-04-06"), convertToLocalDate("2020-11-15")), new DriversLicense(null, "744 849 301", "Full", convertToLocalDate("2017-12-06"), convertToLocalDate("2022-10-15")), new DriversLicense(null, "P626-168-229-765", "Learner", convertToLocalDate("2017-08-16"), convertToLocalDate("2021-11-15")), new DriversLicense(null, "S152-780-97-415-0", "Probationary", convertToLocalDate("2015-08-15"), convertToLocalDate("2021-08-21")) )); private SampleData() { } /** * Converts a date string with the format 'yyyy-MM-dd' into a {@link java.util.Date} object. * * @param date * The date string to convert. * @return {@link LocalDate} or null if there is a {@link ParseException} */ public static synchronized LocalDate convertToLocalDate(String date) { return LocalDate.parse(date, DATE_TIME_FORMAT); } /** * Convert the result set into a list of IonValues. * * @param result * The result set to convert. * @return a list of IonValues. */ public static List toIonValues(Result result) { final List valueList = new ArrayList<>(); result.iterator().forEachRemaining(valueList::add); return valueList; } /** * Get the document ID of a particular document. * * @param txn * A transaction executor object. * @param tableName * Name of the table containing the document. * @param identifier * The identifier used to narrow down the search. * @param value * Value of the identifier. * @return the list of document IDs in the result set. */ public static String getDocumentId(final TransactionExecutor txn, final String tableName, final String identifier, final String value) { try { final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(value)); final String query = String.format("SELECT metadata.id FROM _ql_committed_%s AS p WHERE p.data.%s = ?", tableName, identifier); Result result = txn.execute(query, parameters); if (result.isEmpty()) { throw new IllegalStateException("Unable to retrieve document ID using " + value); } return getStringValueOfStructField((IonStruct) result.iterator().next(), "id"); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Get the document by ID. * * @param qldbSession * A QLDB session. * @param tableName * Name of the table to insert documents into. * @param documentId * The unique ID of a document in the Person table. * @return a {@link QldbRevision} object. * @throws IllegalStateException if failed to convert parameter into {@link IonValue}. */ public static QldbRevision getDocumentById(QldbSession qldbSession, String tableName, String documentId) { try { final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(documentId)); final String query = String.format("SELECT c.* FROM _ql_committed_%s AS c BY docId WHERE docId = ?", tableName); Result result = qldbSession.execute(query, parameters); if (result.isEmpty()) { throw new IllegalStateException("Unable to retrieve document by id " + documentId + " in table " + tableName); } return Constants.MAPPER.readValue(result.iterator().next(), QldbRevision.class); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Return a list of modified document IDs as strings from a DML {@link Result}. * * @param result * The result set from a DML operation. * @return the list of document IDs modified by the operation. */ public static List getDocumentIdsFromDmlResult(final Result result) { final List strings = new ArrayList<>(); result.iterator().forEachRemaining(row -> strings.add(getDocumentIdFromDmlResultDocument(row))); return strings; } /** * Convert the given DML result row's document ID to string. * * @param dmlResultDocument * The {@link IonValue} representing the results of a DML operation. * @return a string of document ID. */ public static String getDocumentIdFromDmlResultDocument(final IonValue dmlResultDocument) { try { DmlResultDocument result = Constants.MAPPER.readValue(dmlResultDocument, DmlResultDocument.class); return result.getDocumentId(); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Get the String value of a given {@link IonStruct} field name. * @param struct the {@link IonStruct} from which to get the value. * @param fieldName the name of the field from which to get the value. * @return the String value of the field within the given {@link IonStruct}. */ public static String getStringValueOfStructField(final IonStruct struct, final String fieldName) { return ((IonString) struct.get(fieldName)).stringValue(); } /** * Return a copy of the given driver's license with updated person Id. * * @param oldLicense * The old driver's license to update. * @param personId * The PersonId of the driver. * @return the updated {@link DriversLicense}. */ public static DriversLicense updatePersonIdDriversLicense(final DriversLicense oldLicense, final String personId) { return new DriversLicense(personId, oldLicense.getLicenseNumber(), oldLicense.getLicenseType(), oldLicense.getValidFromDate(), oldLicense.getValidToDate()); } /** * Return a copy of the given vehicle registration with updated person Id. * * @param oldRegistration * The old vehicle registration to update. * @param personId * The PersonId of the driver. * @return the updated {@link VehicleRegistration}. */ public static VehicleRegistration updateOwnerVehicleRegistration(final VehicleRegistration oldRegistration, final String personId) { return new VehicleRegistration(oldRegistration.getVin(), oldRegistration.getLicensePlateNumber(), oldRegistration.getState(), oldRegistration.getCity(), oldRegistration.getPendingPenaltyTicketAmount(), oldRegistration.getValidFromDate(), oldRegistration.getValidToDate(), new Owners(new Owner(personId), Collections.emptyList())); } } ``` ------ **catatan** Kelas ini menggunakan pustaka Ion untuk menyediakan metode pembantu yang mengonversi data Anda ke dan dari format Ion. `getDocumentId`Metode ini menjalankan query pada tabel dengan awalan`_ql_committed_`. Ini adalah awalan cadangan yang menandakan bahwa Anda ingin menanyakan *tampilan tabel yang berkomitmen*. Dalam tampilan ini, data Anda bersarang di `data` bidang, dan metadata bersarang di bidang. `metadata` 1. Kompilasi dan jalankan program berikut (`CreateTable.java`) untuk membuat tabel yang disebutkan sebelumnya. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; /** * Create tables in a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class CreateTable { public static final Logger log = LoggerFactory.getLogger(CreateTable.class); private CreateTable() { } /** * Registrations, vehicles, owners, and licenses tables being created in a single transaction. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param tableName * Name of the table to be created. * @return the number of tables created. */ public static int createTable(final TransactionExecutor txn, final String tableName) { log.info("Creating the '{}' table...", tableName); final String createTable = String.format("CREATE TABLE %s", tableName); final Result result = txn.execute(createTable); log.info("{} table created successfully.", tableName); return SampleData.toIonValues(result).size(); } public static void main(final String... args) { ConnectToLedger.getDriver().execute(txn -> { createTable(txn, Constants.DRIVERS_LICENSE_TABLE_NAME); createTable(txn, Constants.PERSON_TABLE_NAME); createTable(txn, Constants.VEHICLE_TABLE_NAME); createTable(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME); }); } } ``` ------ #### [ 1.x ] ``` /* * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; /** * Create tables in a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class CreateTable { public static final Logger log = LoggerFactory.getLogger(CreateTable.class); private CreateTable() { } /** * Registrations, vehicles, owners, and licenses tables being created in a single transaction. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param tableName * Name of the table to be created. * @return the number of tables created. */ public static int createTable(final TransactionExecutor txn, final String tableName) { log.info("Creating the '{}' table...", tableName); final String createTable = String.format("CREATE TABLE %s", tableName); final Result result = txn.execute(createTable); log.info("{} table created successfully.", tableName); return SampleData.toIonValues(result).size(); } public static void main(final String... args) { ConnectToLedger.getDriver().execute(txn -> { createTable(txn, Constants.DRIVERS_LICENSE_TABLE_NAME); createTable(txn, Constants.PERSON_TABLE_NAME); createTable(txn, Constants.VEHICLE_TABLE_NAME); createTable(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); } } ``` ------ **catatan** Program ini menunjukkan cara meneruskan `TransactionExecutor` lambda ke metode. `execute` Dalam contoh ini, Anda menjalankan beberapa pernyataan `CREATE TABLE` PartiQL dalam satu transaksi dengan menggunakan ekspresi lambda. `execute`Metode ini secara implisit memulai transaksi, menjalankan semua pernyataan di lambda, dan kemudian melakukan transaksi secara otomatis. 1. Kompilasi dan jalankan program berikut (`CreateIndex.java`) untuk membuat indeks pada tabel, seperti yang dijelaskan sebelumnya. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; /** * Create indexes on tables in a particular ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class CreateIndex { public static final Logger log = LoggerFactory.getLogger(CreateIndex.class); private CreateIndex() { } /** * In this example, create indexes for registrations and vehicles tables. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param tableName * Name of the table to be created. * @param indexAttribute * The index attribute to use. * @return the number of tables created. */ public static int createIndex(final TransactionExecutor txn, final String tableName, final String indexAttribute) { log.info("Creating an index on {}...", indexAttribute); final String createIndex = String.format("CREATE INDEX ON %s (%s)", tableName, indexAttribute); final Result r = txn.execute(createIndex); return SampleData.toIonValues(r).size(); } public static void main(final String... args) { ConnectToLedger.getDriver().execute(txn -> { createIndex(txn, Constants.PERSON_TABLE_NAME, Constants.PERSON_GOV_ID_INDEX_NAME); createIndex(txn, Constants.VEHICLE_TABLE_NAME, Constants.VIN_INDEX_NAME); createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_NUMBER_INDEX_NAME); createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_PERSONID_INDEX_NAME); createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Constants.VIN_INDEX_NAME); createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Constants.VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME); }); log.info("Indexes created successfully!"); } } ``` ------ #### [ 1.x ] ``` /* * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; /** * Create indexes on tables in a particular ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class CreateIndex { public static final Logger log = LoggerFactory.getLogger(CreateIndex.class); private CreateIndex() { } /** * In this example, create indexes for registrations and vehicles tables. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param tableName * Name of the table to be created. * @param indexAttribute * The index attribute to use. * @return the number of tables created. */ public static int createIndex(final TransactionExecutor txn, final String tableName, final String indexAttribute) { log.info("Creating an index on {}...", indexAttribute); final String createIndex = String.format("CREATE INDEX ON %s (%s)", tableName, indexAttribute); final Result r = txn.execute(createIndex); return SampleData.toIonValues(r).size(); } public static void main(final String... args) { ConnectToLedger.getDriver().execute(txn -> { createIndex(txn, Constants.PERSON_TABLE_NAME, Constants.PERSON_GOV_ID_INDEX_NAME); createIndex(txn, Constants.VEHICLE_TABLE_NAME, Constants.VIN_INDEX_NAME); createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_NUMBER_INDEX_NAME); createIndex(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Constants.DRIVER_LICENSE_PERSONID_INDEX_NAME); createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Constants.VIN_INDEX_NAME); createIndex(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Constants.VEHICLE_REGISTRATION_LICENSE_PLATE_NUMBER_INDEX_NAME); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); log.info("Indexes created successfully!"); } } ``` ------ 1. Kompilasi dan jalankan program berikut (`InsertDocument.java`) untuk memasukkan data sampel ke dalam tabel Anda. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazon.ion.IonValue; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.DriversLicense; import software.amazon.qldb.tutorial.model.SampleData; import software.amazon.qldb.tutorial.model.VehicleRegistration; /** * Insert documents into a table in a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class InsertDocument { public static final Logger log = LoggerFactory.getLogger(InsertDocument.class); private InsertDocument() { } /** * Insert the given list of documents into the specified table and return the document IDs of the inserted documents. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param tableName * Name of the table to insert documents into. * @param documents * List of documents to insert into the specified table. * @return a list of document IDs. * @throws IllegalStateException if failed to convert documents into an {@link IonValue}. */ public static List insertDocuments(final TransactionExecutor txn, final String tableName, final List documents) { log.info("Inserting some documents in the {} table...", tableName); try { final String query = String.format("INSERT INTO %s ?", tableName); final IonValue ionDocuments = Constants.MAPPER.writeValueAsIonValue(documents); return SampleData.getDocumentIdsFromDmlResult(txn.execute(query, ionDocuments)); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Update PersonIds in driver's licenses and in vehicle registrations using document IDs. * * @param documentIds * List of document IDs representing the PersonIds in DriversLicense and PrimaryOwners in VehicleRegistration. * @param licenses * List of driver's licenses to update. * @param registrations * List of registrations to update. */ public static void updatePersonId(final List documentIds, final List licenses, final List registrations) { for (int i = 0; i < documentIds.size(); ++i) { DriversLicense license = SampleData.LICENSES.get(i); VehicleRegistration registration = SampleData.REGISTRATIONS.get(i); licenses.add(SampleData.updatePersonIdDriversLicense(license, documentIds.get(i))); registrations.add(SampleData.updateOwnerVehicleRegistration(registration, documentIds.get(i))); } } public static void main(final String... args) { final List newDriversLicenses = new ArrayList<>(); final List newVehicleRegistrations = new ArrayList<>(); ConnectToLedger.getDriver().execute(txn -> { List documentIds = insertDocuments(txn, Constants.PERSON_TABLE_NAME, SampleData.PEOPLE); updatePersonId(documentIds, newDriversLicenses, newVehicleRegistrations); insertDocuments(txn, Constants.VEHICLE_TABLE_NAME, SampleData.VEHICLES); insertDocuments(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Collections.unmodifiableList(newVehicleRegistrations)); insertDocuments(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Collections.unmodifiableList(newDriversLicenses)); }); log.info("Documents inserted successfully!"); } } ``` ------ #### [ 1.x ] ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonValue; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.QldbSession; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.DriversLicense; import software.amazon.qldb.tutorial.model.SampleData; import software.amazon.qldb.tutorial.model.VehicleRegistration; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.List; /** * Insert documents into a table in a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class InsertDocument { public static final Logger log = LoggerFactory.getLogger(InsertDocument.class); private InsertDocument() { } /** * Insert the given list of documents into the specified table and return the document IDs of the inserted documents. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param tableName * Name of the table to insert documents into. * @param documents * List of documents to insert into the specified table. * @return a list of document IDs. * @throws IllegalStateException if failed to convert documents into an {@link IonValue}. */ public static List insertDocuments(final TransactionExecutor txn, final String tableName, final List documents) { log.info("Inserting some documents in the {} table...", tableName); try { final String statement = String.format("INSERT INTO %s ?", tableName); final IonValue ionDocuments = Constants.MAPPER.writeValueAsIonValue(documents); final List parameters = Collections.singletonList(ionDocuments); return SampleData.getDocumentIdsFromDmlResult(txn.execute(statement, parameters)); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Update PersonIds in driver's licenses and in vehicle registrations using document IDs. * * @param documentIds * List of document IDs representing the PersonIds in DriversLicense and PrimaryOwners in VehicleRegistration. * @param licenses * List of driver's licenses to update. * @param registrations * List of registrations to update. */ public static void updatePersonId(final List documentIds, final List licenses, final List registrations) { for (int i = 0; i < documentIds.size(); ++i) { DriversLicense license = SampleData.LICENSES.get(i); VehicleRegistration registration = SampleData.REGISTRATIONS.get(i); licenses.add(SampleData.updatePersonIdDriversLicense(license, documentIds.get(i))); registrations.add(SampleData.updateOwnerVehicleRegistration(registration, documentIds.get(i))); } } public static void main(final String... args) { final List newDriversLicenses = new ArrayList<>(); final List newVehicleRegistrations = new ArrayList<>(); ConnectToLedger.getDriver().execute(txn -> { List documentIds = insertDocuments(txn, Constants.PERSON_TABLE_NAME, SampleData.PEOPLE); updatePersonId(documentIds, newDriversLicenses, newVehicleRegistrations); insertDocuments(txn, Constants.VEHICLE_TABLE_NAME, SampleData.VEHICLES); insertDocuments(txn, Constants.VEHICLE_REGISTRATION_TABLE_NAME, Collections.unmodifiableList(newVehicleRegistrations)); insertDocuments(txn, Constants.DRIVERS_LICENSE_TABLE_NAME, Collections.unmodifiableList(newDriversLicenses)); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); log.info("Documents inserted successfully!"); } } ``` ------ **catatan** Program ini menunjukkan cara memanggil `execute` metode dengan nilai parameter. Anda dapat meneruskan parameter data tipe `IonValue` selain pernyataan PartiQL yang ingin Anda jalankan. Gunakan tanda tanya (`?`) sebagai placeholder variabel dalam string pernyataan Anda. Jika sebuah `INSERT` pernyataan berhasil, ia mengembalikan setiap dokumen `id` yang disisipkan. Selanjutnya, Anda dapat menggunakan `SELECT` pernyataan untuk membaca data dari tabel di `vehicle-registration` buku besar. Lanjut ke [Langkah 4: Kueri tabel dalam buku besar](getting-started.java.step-4.md). # Langkah 4: Kueri tabel dalam buku besar **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Setelah membuat tabel di buku besar QLDB Amazon dan memuatnya dengan data, Anda dapat menjalankan kueri untuk meninjau data registrasi kendaraan yang baru saja Anda masukkan. QLDB [menggunakan](ql-reference.md) PartiQL sebagai [bahasa kueri dan](ion.md) Amazon Ion sebagai model data berorientasi dokumen. PartiQL adalah bahasa kueri open-source yang kompatibel dengan SQL yang telah diperluas untuk bekerja dengan Ion. Dengan PartiQL, Anda dapat menyisipkan, menanyakan, dan mengelola data Anda dengan operator SQL yang sudah dikenal. Amazon Ion adalah superset dari JSON. Ion adalah format data berbasis dokumen open-source yang memberi Anda fleksibilitas dalam menyimpan dan memproses data terstruktur, semi-terstruktur, dan bersarang. Pada langkah ini, Anda menggunakan `SELECT` pernyataan untuk membaca data dari tabel di `vehicle-registration` buku besar. **Awas** Saat Anda menjalankan kueri di QLDB tanpa pencarian yang diindeks, itu akan memanggil pemindaian tabel lengkap. PartiQL mendukung kueri seperti itu karena SQL kompatibel. Namun, *jangan* jalankan pemindaian tabel untuk kasus penggunaan produksi di QLDB. Pemindaian tabel dapat menyebabkan masalah kinerja pada tabel besar, termasuk konflik konkurensi dan batas waktu transaksi. Untuk menghindari pemindaian tabel, Anda harus menjalankan pernyataan dengan klausa `WHERE` predikat menggunakan operator *kesetaraan* pada bidang yang diindeks atau ID dokumen; misalnya, atau. `WHERE indexedField = 123` `WHERE indexedField IN (456, 789)` Untuk informasi selengkapnya, lihat [Mengoptimalkan kinerja kueri](working.optimize.md). **Untuk menanyakan tabel** + Kompilasi dan jalankan program berikut (`FindVehicles.java`) untuk menanyakan semua kendaraan yang terdaftar di bawah seseorang di buku besar Anda. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.io.IOException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazon.ion.IonValue; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.Person; import software.amazon.qldb.tutorial.model.SampleData; /** * Find all vehicles registered under a person. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class FindVehicles { public static final Logger log = LoggerFactory.getLogger(FindVehicles.class); private FindVehicles() { } /** * Find vehicles registered under a driver using their government ID. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param govId * The government ID of the owner. * @throws IllegalStateException if failed to convert parameters into {@link IonValue}. */ public static void findVehiclesForOwner(final TransactionExecutor txn, final String govId) { try { final String documentId = Person.getDocumentIdByGovId(txn, govId); final String query = "SELECT v FROM Vehicle AS v INNER JOIN VehicleRegistration AS r " + "ON v.VIN = r.VIN WHERE r.Owners.PrimaryOwner.PersonId = ?"; final Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId)); log.info("List of Vehicles for owner with GovId: {}...", govId); ScanTable.printDocuments(result); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final Person person = SampleData.PEOPLE.get(0); ConnectToLedger.getDriver().execute(txn -> { findVehiclesForOwner(txn, person.getGovId()); }); } } ``` ------ #### [ 1.x ] ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.io.IOException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazon.ion.IonValue; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.Person; import software.amazon.qldb.tutorial.model.SampleData; /** * Find all vehicles registered under a person. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class FindVehicles { public static final Logger log = LoggerFactory.getLogger(FindVehicles.class); private FindVehicles() { } /** * Find vehicles registered under a driver using their government ID. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param govId * The government ID of the owner. * @throws IllegalStateException if failed to convert parameters into {@link IonValue}. */ public static void findVehiclesForOwner(final TransactionExecutor txn, final String govId) { try { final String documentId = Person.getDocumentIdByGovId(txn, govId); final String query = "SELECT v FROM Vehicle AS v INNER JOIN VehicleRegistration AS r " + "ON v.VIN = r.VIN WHERE r.Owners.PrimaryOwner.PersonId = ?"; final Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId)); log.info("List of Vehicles for owner with GovId: {}...", govId); ScanTable.printDocuments(result); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final Person person = SampleData.PEOPLE.get(0); ConnectToLedger.getDriver().execute(txn -> { findVehiclesForOwner(txn, person.getGovId()); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); } } ``` ------ **catatan** Pertama, program ini menanyakan `Person` tabel untuk dokumen `GovId LEWISR261LL` untuk mendapatkan bidang `id` metadata-nya. Kemudian, ia menggunakan dokumen ini `id` sebagai kunci asing untuk menanyakan `VehicleRegistration` tabel dengan`PrimaryOwner.PersonId`. Itu juga bergabung `VehicleRegistration` dengan `Vehicle` meja di `VIN` lapangan. Untuk mempelajari tentang memodifikasi dokumen dalam tabel di `vehicle-registration` buku besar, lihat. [Langkah 5: Ubah dokumen dalam buku besar](getting-started.java.step-5.md) # Langkah 5: Ubah dokumen dalam buku besar **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Sekarang setelah Anda memiliki data untuk dikerjakan, Anda dapat mulai membuat perubahan pada dokumen di `vehicle-registration` buku besar di Amazon QLDB. Pada langkah ini, contoh kode berikut menunjukkan bagaimana menjalankan pernyataan bahasa manipulasi data (DHTML). Pernyataan ini memperbarui pemilik utama satu kendaraan dan menambahkan pemilik sekunder ke kendaraan lain. **Untuk memodifikasi dokumen** 1. Kompilasi dan jalankan program berikut (`TransferVehicleOwnership.java`) untuk memperbarui pemilik utama kendaraan dengan VIN `1N4AL11D75C109151` di buku besar Anda. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonReader; import com.amazon.ion.IonStruct; import com.amazon.ion.IonValue; import com.amazon.ion.system.IonReaderBuilder; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.LinkedHashMap; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.Owner; import software.amazon.qldb.tutorial.model.Person; import software.amazon.qldb.tutorial.model.SampleData; /** * Find primary owner for a particular vehicle's VIN. * Transfer to another primary owner for a particular vehicle's VIN. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class TransferVehicleOwnership { public static final Logger log = LoggerFactory.getLogger(TransferVehicleOwnership.class); private TransferVehicleOwnership() { } /** * Query a driver's information using the given ID. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param documentId * The unique ID of a document in the Person table. * @return a {@link Person} object. * @throws IllegalStateException if failed to convert parameter into {@link IonValue}. */ public static Person findPersonFromDocumentId(final TransactionExecutor txn, final String documentId) { try { log.info("Finding person for documentId: {}...", documentId); final String query = "SELECT p.* FROM Person AS p BY pid WHERE pid = ?"; Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId)); if (result.isEmpty()) { throw new IllegalStateException("Unable to find person with ID: " + documentId); } return Constants.MAPPER.readValue(result.iterator().next(), Person.class); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Find the primary owner for the given VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @return a {@link Person} object. * @throws IllegalStateException if failed to convert parameter into {@link IonValue}. */ public static Person findPrimaryOwnerForVehicle(final TransactionExecutor txn, final String vin) { try { log.info("Finding primary owner for vehicle with Vin: {}...", vin); final String query = "SELECT Owners.PrimaryOwner.PersonId FROM VehicleRegistration AS v WHERE v.VIN = ?"; final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin)); Result result = txn.execute(query, parameters); final List documents = ScanTable.toIonStructs(result); ScanTable.printDocuments(documents); if (documents.isEmpty()) { throw new IllegalStateException("Unable to find registrations with VIN: " + vin); } final IonReader reader = IonReaderBuilder.standard().build(documents.get(0)); final String personId = Constants.MAPPER.readValue(reader, LinkedHashMap.class).get("PersonId").toString(); return findPersonFromDocumentId(txn, personId); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Update the primary owner for a vehicle registration with the given documentId. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @param documentId * New PersonId for the primary owner. * @throws IllegalStateException if no vehicle registration was found using the given document ID and VIN, or if failed * to convert parameters into {@link IonValue}. */ public static void updateVehicleRegistration(final TransactionExecutor txn, final String vin, final String documentId) { try { log.info("Updating primary owner for vehicle with Vin: {}...", vin); final String query = "UPDATE VehicleRegistration AS v SET v.Owners.PrimaryOwner = ? WHERE v.VIN = ?"; final List parameters = new ArrayList<>(); parameters.add(Constants.MAPPER.writeValueAsIonValue(new Owner(documentId))); parameters.add(Constants.MAPPER.writeValueAsIonValue(vin)); Result result = txn.execute(query, parameters); ScanTable.printDocuments(result); if (result.isEmpty()) { throw new IllegalStateException("Unable to transfer vehicle, could not find registration."); } else { log.info("Successfully transferred vehicle with VIN '{}' to new owner.", vin); } } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final String vin = SampleData.VEHICLES.get(0).getVin(); final String primaryOwnerGovId = SampleData.PEOPLE.get(0).getGovId(); final String newPrimaryOwnerGovId = SampleData.PEOPLE.get(1).getGovId(); ConnectToLedger.getDriver().execute(txn -> { final Person primaryOwner = findPrimaryOwnerForVehicle(txn, vin); if (!primaryOwner.getGovId().equals(primaryOwnerGovId)) { // Verify the primary owner. throw new IllegalStateException("Incorrect primary owner identified for vehicle, unable to transfer."); } final String newOwner = Person.getDocumentIdByGovId(txn, newPrimaryOwnerGovId); updateVehicleRegistration(txn, vin, newOwner); }); log.info("Successfully transferred vehicle ownership!"); } } ``` ------ #### [ 1.x ] ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonReader; import com.amazon.ion.IonStruct; import com.amazon.ion.IonValue; import com.amazon.ion.system.IonReaderBuilder; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.LinkedHashMap; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.Owner; import software.amazon.qldb.tutorial.model.Person; import software.amazon.qldb.tutorial.model.SampleData; /** * Find primary owner for a particular vehicle's VIN. * Transfer to another primary owner for a particular vehicle's VIN. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class TransferVehicleOwnership { public static final Logger log = LoggerFactory.getLogger(TransferVehicleOwnership.class); private TransferVehicleOwnership() { } /** * Query a driver's information using the given ID. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param documentId * The unique ID of a document in the Person table. * @return a {@link Person} object. * @throws IllegalStateException if failed to convert parameter into {@link IonValue}. */ public static Person findPersonFromDocumentId(final TransactionExecutor txn, final String documentId) { try { log.info("Finding person for documentId: {}...", documentId); final String query = "SELECT p.* FROM Person AS p BY pid WHERE pid = ?"; Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(documentId)); if (result.isEmpty()) { throw new IllegalStateException("Unable to find person with ID: " + documentId); } return Constants.MAPPER.readValue(result.iterator().next(), Person.class); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Find the primary owner for the given VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @return a {@link Person} object. * @throws IllegalStateException if failed to convert parameter into {@link IonValue}. */ public static Person findPrimaryOwnerForVehicle(final TransactionExecutor txn, final String vin) { try { log.info("Finding primary owner for vehicle with Vin: {}...", vin); final String query = "SELECT Owners.PrimaryOwner.PersonId FROM VehicleRegistration AS v WHERE v.VIN = ?"; final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin)); Result result = txn.execute(query, parameters); final List documents = ScanTable.toIonStructs(result); ScanTable.printDocuments(documents); if (documents.isEmpty()) { throw new IllegalStateException("Unable to find registrations with VIN: " + vin); } final IonReader reader = IonReaderBuilder.standard().build(documents.get(0)); final String personId = Constants.MAPPER.readValue(reader, LinkedHashMap.class).get("PersonId").toString(); return findPersonFromDocumentId(txn, personId); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Update the primary owner for a vehicle registration with the given documentId. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @param documentId * New PersonId for the primary owner. * @throws IllegalStateException if no vehicle registration was found using the given document ID and VIN, or if failed * to convert parameters into {@link IonValue}. */ public static void updateVehicleRegistration(final TransactionExecutor txn, final String vin, final String documentId) { try { log.info("Updating primary owner for vehicle with Vin: {}...", vin); final String query = "UPDATE VehicleRegistration AS v SET v.Owners.PrimaryOwner = ? WHERE v.VIN = ?"; final List parameters = new ArrayList<>(); parameters.add(Constants.MAPPER.writeValueAsIonValue(new Owner(documentId))); parameters.add(Constants.MAPPER.writeValueAsIonValue(vin)); Result result = txn.execute(query, parameters); ScanTable.printDocuments(result); if (result.isEmpty()) { throw new IllegalStateException("Unable to transfer vehicle, could not find registration."); } else { log.info("Successfully transferred vehicle with VIN '{}' to new owner.", vin); } } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final String vin = SampleData.VEHICLES.get(0).getVin(); final String primaryOwnerGovId = SampleData.PEOPLE.get(0).getGovId(); final String newPrimaryOwnerGovId = SampleData.PEOPLE.get(1).getGovId(); ConnectToLedger.getDriver().execute(txn -> { final Person primaryOwner = findPrimaryOwnerForVehicle(txn, vin); if (!primaryOwner.getGovId().equals(primaryOwnerGovId)) { // Verify the primary owner. throw new IllegalStateException("Incorrect primary owner identified for vehicle, unable to transfer."); } final String newOwner = Person.getDocumentIdByGovId(txn, newPrimaryOwnerGovId); updateVehicleRegistration(txn, vin, newOwner); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); log.info("Successfully transferred vehicle ownership!"); } } ``` ------ 1. Kompilasi dan jalankan program berikut (`AddSecondaryOwner.java`) untuk menambahkan pemilik sekunder ke kendaraan dengan VIN `KM8SRDHF6EU074761` di buku besar Anda. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.io.IOException; import java.util.Collections; import java.util.Iterator; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazon.ion.IonValue; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.Owner; import software.amazon.qldb.tutorial.model.Owners; import software.amazon.qldb.tutorial.model.Person; import software.amazon.qldb.tutorial.model.SampleData; /** * Finds and adds secondary owners for a vehicle. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class AddSecondaryOwner { public static final Logger log = LoggerFactory.getLogger(AddSecondaryOwner.class); private AddSecondaryOwner() { } /** * Check whether a secondary owner has already been registered for the given VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @param secondaryOwnerId * The secondary owner to add. * @return {@code true} if the given secondary owner has already been registered, {@code false} otherwise. * @throws IllegalStateException if failed to convert VIN to an {@link IonValue}. */ public static boolean isSecondaryOwnerForVehicle(final TransactionExecutor txn, final String vin, final String secondaryOwnerId) { try { log.info("Finding secondary owners for vehicle with VIN: {}...", vin); final String query = "SELECT Owners.SecondaryOwners FROM VehicleRegistration AS v WHERE v.VIN = ?"; final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin)); final Result result = txn.execute(query, parameters); final Iterator itr = result.iterator(); if (!itr.hasNext()) { return false; } final Owners owners = Constants.MAPPER.readValue(itr.next(), Owners.class); if (null != owners.getSecondaryOwners()) { for (Owner owner : owners.getSecondaryOwners()) { if (secondaryOwnerId.equalsIgnoreCase(owner.getPersonId())) { return true; } } } return false; } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Adds a secondary owner for the specified VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @param secondaryOwner * The secondary owner to add. * @throws IllegalStateException if failed to convert parameter into an {@link IonValue}. */ public static void addSecondaryOwnerForVin(final TransactionExecutor txn, final String vin, final String secondaryOwner) { try { log.info("Inserting secondary owner for vehicle with VIN: {}...", vin); final String query = String.format("FROM VehicleRegistration AS v WHERE v.VIN = ?" + "INSERT INTO v.Owners.SecondaryOwners VALUE ?"); final IonValue newOwner = Constants.MAPPER.writeValueAsIonValue(new Owner(secondaryOwner)); final IonValue vinAsIonValue = Constants.MAPPER.writeValueAsIonValue(vin); Result result = txn.execute(query, vinAsIonValue, newOwner); log.info("VehicleRegistration Document IDs which had secondary owners added: "); ScanTable.printDocuments(result); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final String vin = SampleData.VEHICLES.get(1).getVin(); final String govId = SampleData.PEOPLE.get(0).getGovId(); ConnectToLedger.getDriver().execute(txn -> { final String documentId = Person.getDocumentIdByGovId(txn, govId); if (isSecondaryOwnerForVehicle(txn, vin, documentId)) { log.info("Person with ID {} has already been added as a secondary owner of this vehicle.", govId); } else { addSecondaryOwnerForVin(txn, vin, documentId); } }); log.info("Secondary owners successfully updated."); } } ``` ------ #### [ 1.x ] ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.io.IOException; import java.util.Collections; import java.util.Iterator; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazon.ion.IonValue; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.Owner; import software.amazon.qldb.tutorial.model.Owners; import software.amazon.qldb.tutorial.model.Person; import software.amazon.qldb.tutorial.model.SampleData; /** * Finds and adds secondary owners for a vehicle. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class AddSecondaryOwner { public static final Logger log = LoggerFactory.getLogger(AddSecondaryOwner.class); private AddSecondaryOwner() { } /** * Check whether a secondary owner has already been registered for the given VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @param secondaryOwnerId * The secondary owner to add. * @return {@code true} if the given secondary owner has already been registered, {@code false} otherwise. * @throws IllegalStateException if failed to convert VIN to an {@link IonValue}. */ public static boolean isSecondaryOwnerForVehicle(final TransactionExecutor txn, final String vin, final String secondaryOwnerId) { try { log.info("Finding secondary owners for vehicle with VIN: {}...", vin); final String query = "SELECT Owners.SecondaryOwners FROM VehicleRegistration AS v WHERE v.VIN = ?"; final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin)); final Result result = txn.execute(query, parameters); final Iterator itr = result.iterator(); if (!itr.hasNext()) { return false; } final Owners owners = Constants.MAPPER.readValue(itr.next(), Owners.class); if (null != owners.getSecondaryOwners()) { for (Owner owner : owners.getSecondaryOwners()) { if (secondaryOwnerId.equalsIgnoreCase(owner.getPersonId())) { return true; } } } return false; } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Adds a secondary owner for the specified VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * Unique VIN for a vehicle. * @param secondaryOwner * The secondary owner to add. * @throws IllegalStateException if failed to convert parameter into an {@link IonValue}. */ public static void addSecondaryOwnerForVin(final TransactionExecutor txn, final String vin, final String secondaryOwner) { try { log.info("Inserting secondary owner for vehicle with VIN: {}...", vin); final String query = String.format("FROM VehicleRegistration AS v WHERE v.VIN = '%s' " + "INSERT INTO v.Owners.SecondaryOwners VALUE ?", vin); final IonValue newOwner = Constants.MAPPER.writeValueAsIonValue(new Owner(secondaryOwner)); Result result = txn.execute(query, newOwner); log.info("VehicleRegistration Document IDs which had secondary owners added: "); ScanTable.printDocuments(result); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final String vin = SampleData.VEHICLES.get(1).getVin(); final String govId = SampleData.PEOPLE.get(0).getGovId(); ConnectToLedger.getDriver().execute(txn -> { final String documentId = Person.getDocumentIdByGovId(txn, govId); if (isSecondaryOwnerForVehicle(txn, vin, documentId)) { log.info("Person with ID {} has already been added as a secondary owner of this vehicle.", govId); } else { addSecondaryOwnerForVin(txn, vin, documentId); } }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); log.info("Secondary owners successfully updated."); } } ``` ------ Untuk meninjau perubahan ini di `vehicle-registration` buku besar, lihat[Langkah 6: Lihat riwayat revisi untuk dokumen](getting-started.java.step-6.md). # Langkah 6: Lihat riwayat revisi untuk dokumen **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Setelah memodifikasi data registrasi untuk kendaraan pada langkah sebelumnya, Anda dapat menanyakan riwayat semua pemilik terdaftar dan bidang yang diperbarui lainnya. Pada langkah ini, Anda menanyakan riwayat revisi dokumen dalam `VehicleRegistration` tabel di `vehicle-registration` buku besar Anda. **Untuk melihat riwayat revisi** 1. Tinjau program berikut (`QueryHistory.java`). ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.io.IOException; import java.time.Instant; import java.time.temporal.ChronoUnit; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazon.ion.IonValue; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; import software.amazon.qldb.tutorial.model.VehicleRegistration; /** * Query a table's history for a particular set of documents. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class QueryHistory { public static final Logger log = LoggerFactory.getLogger(QueryHistory.class); private static final int THREE_MONTHS = 90; private QueryHistory() { } /** * In this example, query the 'VehicleRegistration' history table to find all previous primary owners for a VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * VIN to find previous primary owners for. * @param query * The query to find previous primary owners. * @throws IllegalStateException if failed to convert document ID to an {@link IonValue}. */ public static void previousPrimaryOwners(final TransactionExecutor txn, final String vin, final String query) { try { final String docId = VehicleRegistration.getDocumentIdByVin(txn, vin); log.info("Querying the 'VehicleRegistration' table's history using VIN: {}...", vin); final Result result = txn.execute(query, Constants.MAPPER.writeValueAsIonValue(docId)); ScanTable.printDocuments(result); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final String threeMonthsAgo = Instant.now().minus(THREE_MONTHS, ChronoUnit.DAYS).toString(); final String query = String.format("SELECT data.Owners.PrimaryOwner, metadata.version " + "FROM history(VehicleRegistration, `%s`) " + "AS h WHERE h.metadata.id = ?", threeMonthsAgo); ConnectToLedger.getDriver().execute(txn -> { final String vin = SampleData.VEHICLES.get(0).getVin(); previousPrimaryOwners(txn, vin, query); }); log.info("Successfully queried history."); } } ``` ------ #### [ 1.x ] ``` /* * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonValue; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.QldbSession; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; import software.amazon.qldb.tutorial.model.VehicleRegistration; import java.io.IOException; import java.time.Instant; import java.time.temporal.ChronoUnit; import java.util.Collections; import java.util.List; /** * Query a table's history for a particular set of documents. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class QueryHistory { public static final Logger log = LoggerFactory.getLogger(QueryHistory.class); private static final int THREE_MONTHS = 90; private QueryHistory() { } /** * In this example, query the 'VehicleRegistration' history table to find all previous primary owners for a VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * VIN to find previous primary owners for. * @param query * The query to find previous primary owners. * @throws IllegalStateException if failed to convert document ID to an {@link IonValue}. */ public static void previousPrimaryOwners(final TransactionExecutor txn, final String vin, final String query) { try { final String docId = VehicleRegistration.getDocumentIdByVin(txn, vin); final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(docId)); log.info("Querying the 'VehicleRegistration' table's history using VIN: {}...", vin); final Result result = txn.execute(query, parameters); ScanTable.printDocuments(result); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } public static void main(final String... args) { final String threeMonthsAgo = Instant.now().minus(THREE_MONTHS, ChronoUnit.DAYS).toString(); final String query = String.format("SELECT data.Owners.PrimaryOwner, metadata.version " + "FROM history(VehicleRegistration, `%s`) " + "AS h WHERE h.metadata.id = ?", threeMonthsAgo); ConnectToLedger.getDriver().execute(txn -> { final String vin = SampleData.VEHICLES.get(0).getVin(); previousPrimaryOwners(txn, vin, query); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); log.info("Successfully queried history."); } } ``` ------ **catatan** Anda dapat melihat riwayat revisi dokumen dengan menanyakan built-in [Fungsi sejarah](working.history.md#working.history.function) dalam sintaks berikut. ``` SELECT * FROM history( table_name [, `start-time` [, `end-time` ] ] ) AS h [ WHERE h.metadata.id = 'id' ] ``` Waktu *mulai dan akhir waktu* *keduanya opsional*. Itu adalah nilai literal Amazon Ion yang dapat dilambangkan dengan backticks (). ``...`` Untuk mempelajari selengkapnya, lihat [Meminta Ion dengan PartiQL di Amazon QLDB](ql-reference.query.md). Sebagai praktik terbaik, kualifikasikan kueri riwayat dengan rentang tanggal (waktu mulai *dan *akhir waktu**) dan ID dokumen (). `metadata.id` [QLDB `SELECT` memproses kueri dalam transaksi, yang tunduk pada batas waktu tunggu transaksi.](limits.md#limits.fixed) Riwayat QLDB diindeks oleh ID dokumen, dan Anda tidak dapat membuat indeks riwayat tambahan saat ini. Pertanyaan sejarah yang mencakup waktu mulai dan waktu akhir mendapatkan manfaat dari kualifikasi rentang tanggal. 1. Kompilasi dan jalankan `QueryHistory.java` program untuk menanyakan riwayat revisi `VehicleRegistration` dokumen dengan VIN. `1N4AL11D75C109151` Untuk memverifikasi revisi dokumen secara kriptografis di `vehicle-registration` buku besar, lanjutkan ke. [Langkah 7: Verifikasi dokumen dalam buku besar](getting-started.java.step-7.md) # Langkah 7: Verifikasi dokumen dalam buku besar **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Dengan Amazon QLDB, Anda dapat memverifikasi integritas dokumen secara efisien dalam jurnal buku besar Anda dengan menggunakan hashing kriptografi dengan SHA-256. Untuk mempelajari lebih lanjut tentang cara kerja verifikasi dan hashing kriptografi di QLDB, lihat. [Verifikasi data di Amazon QLDB](verification.md) Pada langkah ini, Anda memverifikasi revisi dokumen dalam `VehicleRegistration` tabel di `vehicle-registration` buku besar Anda. Pertama, Anda meminta intisari, yang dikembalikan sebagai file output dan bertindak sebagai tanda tangan dari seluruh riwayat perubahan buku besar Anda. Kemudian, Anda meminta bukti untuk revisi relatif terhadap intisari itu. Dengan menggunakan bukti ini, integritas revisi Anda diverifikasi jika semua pemeriksaan validasi lulus. **Untuk memverifikasi revisi dokumen** 1. Tinjau `.java` file berikut, yang mewakili objek QLDB yang diperlukan untuk verifikasi dan kelas utilitas dengan metode pembantu untuk nilai Ion dan string. 1. `BlockAddress.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import java.util.Objects; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; /** * Represents the BlockAddress field of a QLDB document. */ public final class BlockAddress { private static final Logger log = LoggerFactory.getLogger(BlockAddress.class); private final String strandId; private final long sequenceNo; @JsonCreator public BlockAddress(@JsonProperty("strandId") final String strandId, @JsonProperty("sequenceNo") final long sequenceNo) { this.strandId = strandId; this.sequenceNo = sequenceNo; } public long getSequenceNo() { return sequenceNo; } public String getStrandId() { return strandId; } @Override public String toString() { return "BlockAddress{" + "strandId='" + strandId + '\'' + ", sequenceNo=" + sequenceNo + '}'; } @Override public boolean equals(final Object o) { if (this == o) { return true; } if (o == null || getClass() != o.getClass()) { return false; } BlockAddress that = (BlockAddress) o; return sequenceNo == that.sequenceNo && strandId.equals(that.strandId); } @Override public int hashCode() { // CHECKSTYLE:OFF - Disabling as we are generating a hashCode of multiple properties. return Objects.hash(strandId, sequenceNo); // CHECKSTYLE:ON } } ``` 1. `Proof.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.amazon.ion.IonReader; import com.amazon.ion.IonSystem; import com.amazon.ion.system.IonSystemBuilder; import com.amazonaws.services.qldb.model.GetRevisionRequest; import com.amazonaws.services.qldb.model.GetRevisionResult; import java.util.ArrayList; import java.util.List; /** * A Java representation of the {@link Proof} object. * Returned from the {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision(GetRevisionRequest)} api. */ public final class Proof { private static final IonSystem SYSTEM = IonSystemBuilder.standard().build(); private List internalHashes; public Proof(final List internalHashes) { this.internalHashes = internalHashes; } public List getInternalHashes() { return internalHashes; } /** * Decodes a {@link Proof} from an ion text String. This ion text is returned in * a {@link GetRevisionResult#getProof()} * * @param ionText * The ion text representing a {@link Proof} object. * @return {@link JournalBlock} parsed from the ion text. * @throws IllegalStateException if failed to parse the {@link Proof} object from the given ion text. */ public static Proof fromBlob(final String ionText) { try { IonReader reader = SYSTEM.newReader(ionText); List list = new ArrayList<>(); reader.next(); reader.stepIn(); while (reader.next() != null) { list.add(reader.newBytes()); } return new Proof(list); } catch (Exception e) { throw new IllegalStateException("Failed to parse a Proof from byte array"); } } } ``` 1. `QldbIonUtils.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.amazon.ion.IonReader; import com.amazon.ion.IonValue; import com.amazon.ionhash.IonHashReader; import com.amazon.ionhash.IonHashReaderBuilder; import com.amazon.ionhash.MessageDigestIonHasherProvider; import software.amazon.qldb.tutorial.Constants; public class QldbIonUtils { private static MessageDigestIonHasherProvider ionHasherProvider = new MessageDigestIonHasherProvider("SHA-256"); private QldbIonUtils() {} /** * Builds a hash value from the given {@link IonValue}. * * @param ionValue * The {@link IonValue} to hash. * @return a byte array representing the hash value. */ public static byte[] hashIonValue(final IonValue ionValue) { IonReader reader = Constants.SYSTEM.newReader(ionValue); IonHashReader hashReader = IonHashReaderBuilder.standard() .withHasherProvider(ionHasherProvider) .withReader(reader) .build(); while (hashReader.next() != null) { } return hashReader.digest(); } } ``` 1. `QldbStringUtils.java` ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.amazon.ion.IonWriter; import com.amazon.ion.system.IonReaderBuilder; import com.amazon.ion.system.IonTextWriterBuilder; import com.amazonaws.services.qldb.model.GetBlockResult; import com.amazonaws.services.qldb.model.GetDigestResult; import com.amazonaws.services.qldb.model.ValueHolder; import java.io.IOException; /** * Helper methods to pretty-print certain QLDB response types. */ public class QldbStringUtils { private QldbStringUtils() {} /** * Returns the string representation of a given {@link ValueHolder}. * Adapted from the AWS SDK autogenerated {@code toString()} method, with sensitive values un-redacted. * Additionally, this method pretty-prints any IonText included in the {@link ValueHolder}. * * @param valueHolder the {@link ValueHolder} to convert to a String. * @return the String representation of the supplied {@link ValueHolder}. */ public static String toUnredactedString(ValueHolder valueHolder) { StringBuilder sb = new StringBuilder(); sb.append("{"); if (valueHolder.getIonText() != null) { sb.append("IonText: "); IonWriter prettyWriter = IonTextWriterBuilder.pretty().build(sb); try { prettyWriter.writeValues(IonReaderBuilder.standard().build(valueHolder.getIonText())); } catch (IOException ioe) { sb.append("**Exception while printing this IonText**"); } } sb.append("}"); return sb.toString(); } /** * Returns the string representation of a given {@link GetBlockResult}. * Adapted from the AWS SDK autogenerated {@code toString()} method, with sensitive values un-redacted. * * @param getBlockResult the {@link GetBlockResult} to convert to a String. * @return the String representation of the supplied {@link GetBlockResult}. */ public static String toUnredactedString(GetBlockResult getBlockResult) { StringBuilder sb = new StringBuilder(); sb.append("{"); if (getBlockResult.getBlock() != null) { sb.append("Block: ").append(toUnredactedString(getBlockResult.getBlock())).append(","); } if (getBlockResult.getProof() != null) { sb.append("Proof: ").append(toUnredactedString(getBlockResult.getProof())); } sb.append("}"); return sb.toString(); } /** * Returns the string representation of a given {@link GetDigestResult}. * Adapted from the AWS SDK autogenerated {@code toString()} method, with sensitive values un-redacted. * * @param getDigestResult the {@link GetDigestResult} to convert to a String. * @return the String representation of the supplied {@link GetDigestResult}. */ public static String toUnredactedString(GetDigestResult getDigestResult) { StringBuilder sb = new StringBuilder(); sb.append("{"); if (getDigestResult.getDigest() != null) { sb.append("Digest: ").append(getDigestResult.getDigest()).append(","); } if (getDigestResult.getDigestTipAddress() != null) { sb.append("DigestTipAddress: ").append(toUnredactedString(getDigestResult.getDigestTipAddress())); } sb.append("}"); return sb.toString(); } } ``` 1. `Verifier.java` ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import java.nio.ByteBuffer; import java.nio.charset.StandardCharsets; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.ArrayList; import java.util.Arrays; import java.util.Comparator; import java.util.Iterator; import java.util.List; import java.util.concurrent.ThreadLocalRandom; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazonaws.util.Base64; import software.amazon.qldb.tutorial.qldb.Proof; /** * Encapsulates the logic to verify the integrity of revisions or blocks in a QLDB ledger. * * The main entry point is {@link #verify(byte[], byte[], String)}. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class Verifier { public static final Logger log = LoggerFactory.getLogger(Verifier.class); private static final int HASH_LENGTH = 32; private static final int UPPER_BOUND = 8; /** * Compares two hashes by their signed byte values in little-endian order. */ private static Comparator hashComparator = (h1, h2) -> { if (h1.length != HASH_LENGTH || h2.length != HASH_LENGTH) { throw new IllegalArgumentException("Invalid hash."); } for (int i = h1.length - 1; i >= 0; i--) { int byteEqual = Byte.compare(h1[i], h2[i]); if (byteEqual != 0) { return byteEqual; } } return 0; }; private Verifier() { } /** * Verify the integrity of a document with respect to a QLDB ledger digest. * * The verification algorithm includes the following steps: * * 1. {@link #buildCandidateDigest(Proof, byte[])} build the candidate digest from the internal hashes * in the {@link Proof}. * 2. Check that the {@code candidateLedgerDigest} is equal to the {@code ledgerDigest}. * * @param documentHash * The hash of the document to be verified. * @param digest * The QLDB ledger digest. This digest should have been retrieved using * {@link com.amazonaws.services.qldb.AmazonQLDB#getDigest} * @param proofBlob * The ion encoded bytes representing the {@link Proof} associated with the supplied * {@code digestTipAddress} and {@code address} retrieved using * {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}. * @return {@code true} if the record is verified or {@code false} if it is not verified. */ public static boolean verify( final byte[] documentHash, final byte[] digest, final String proofBlob ) { Proof proof = Proof.fromBlob(proofBlob); byte[] candidateDigest = buildCandidateDigest(proof, documentHash); return Arrays.equals(digest, candidateDigest); } /** * Build the candidate digest representing the entire ledger from the internal hashes of the {@link Proof}. * * @param proof * A Java representation of {@link Proof} * returned from {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}. * @param leafHash * Leaf hash to build the candidate digest with. * @return a byte array of the candidate digest. */ private static byte[] buildCandidateDigest(final Proof proof, final byte[] leafHash) { return calculateRootHashFromInternalHashes(proof.getInternalHashes(), leafHash); } /** * Get a new instance of {@link MessageDigest} using the SHA-256 algorithm. * * @return an instance of {@link MessageDigest}. * @throws IllegalStateException if the algorithm is not available on the current JVM. */ static MessageDigest newMessageDigest() { try { return MessageDigest.getInstance("SHA-256"); } catch (NoSuchAlgorithmException e) { log.error("Failed to create SHA-256 MessageDigest", e); throw new IllegalStateException("SHA-256 message digest is unavailable", e); } } /** * Takes two hashes, sorts them, concatenates them, and then returns the * hash of the concatenated array. * * @param h1 * Byte array containing one of the hashes to compare. * @param h2 * Byte array containing one of the hashes to compare. * @return the concatenated array of hashes. */ public static byte[] dot(final byte[] h1, final byte[] h2) { if (h1.length == 0) { return h2; } if (h2.length == 0) { return h1; } byte[] concatenated = new byte[h1.length + h2.length]; if (hashComparator.compare(h1, h2) < 0) { System.arraycopy(h1, 0, concatenated, 0, h1.length); System.arraycopy(h2, 0, concatenated, h1.length, h2.length); } else { System.arraycopy(h2, 0, concatenated, 0, h2.length); System.arraycopy(h1, 0, concatenated, h2.length, h1.length); } MessageDigest messageDigest = newMessageDigest(); messageDigest.update(concatenated); return messageDigest.digest(); } /** * Starting with the provided {@code leafHash} combined with the provided {@code internalHashes} * pairwise until only the root hash remains. * * @param internalHashes * Internal hashes of Merkle tree. * @param leafHash * Leaf hashes of Merkle tree. * @return the root hash. */ private static byte[] calculateRootHashFromInternalHashes(final List internalHashes, final byte[] leafHash) { return internalHashes.stream().reduce(leafHash, Verifier::dot); } /** * Flip a single random bit in the given byte array. This method is used to demonstrate * QLDB's verification features. * * @param original * The original byte array. * @return the altered byte array with a single random bit changed. */ public static byte[] flipRandomBit(final byte[] original) { if (original.length == 0) { throw new IllegalArgumentException("Array cannot be empty!"); } int alteredPosition = ThreadLocalRandom.current().nextInt(original.length); int b = ThreadLocalRandom.current().nextInt(UPPER_BOUND); byte[] altered = new byte[original.length]; System.arraycopy(original, 0, altered, 0, original.length); altered[alteredPosition] = (byte) (altered[alteredPosition] ^ (1 << b)); return altered; } public static String toBase64(byte[] arr) { return new String(Base64.encode(arr), StandardCharsets.UTF_8); } /** * Convert a {@link ByteBuffer} into byte array. * * @param buffer * The {@link ByteBuffer} to convert. * @return the converted byte array. */ public static byte[] convertByteBufferToByteArray(final ByteBuffer buffer) { byte[] arr = new byte[buffer.remaining()]; buffer.get(arr); return arr; } /** * Calculates the root hash from a list of hashes that represent the base of a Merkle tree. * * @param hashes * The list of byte arrays representing hashes making up base of a Merkle tree. * @return a byte array that is the root hash of the given list of hashes. */ public static byte[] calculateMerkleTreeRootHash(List hashes) { if (hashes.isEmpty()) { return new byte[0]; } List remaining = combineLeafHashes(hashes); while (remaining.size() > 1) { remaining = combineLeafHashes(remaining); } return remaining.get(0); } private static List combineLeafHashes(List hashes) { List combinedHashes = new ArrayList<>(); Iterator it = hashes.stream().iterator(); while (it.hasNext()) { byte[] left = it.next(); if (it.hasNext()) { byte[] right = it.next(); byte[] combined = dot(left, right); combinedHashes.add(combined); } else { combinedHashes.add(left); } } return combinedHashes; } } ``` ------ #### [ 1.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.util.Base64; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.tutorial.qldb.Proof; import java.nio.ByteBuffer; import java.nio.charset.StandardCharsets; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.*; import java.util.concurrent.ThreadLocalRandom; /** * Encapsulates the logic to verify the integrity of revisions or blocks in a QLDB ledger. * * The main entry point is {@link #verify(byte[], byte[], String)}. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class Verifier { public static final Logger log = LoggerFactory.getLogger(Verifier.class); private static final int HASH_LENGTH = 32; private static final int UPPER_BOUND = 8; /** * Compares two hashes by their signed byte values in little-endian order. */ private static Comparator hashComparator = (h1, h2) -> { if (h1.length != HASH_LENGTH || h2.length != HASH_LENGTH) { throw new IllegalArgumentException("Invalid hash."); } for (int i = h1.length - 1; i >= 0; i--) { int byteEqual = Byte.compare(h1[i], h2[i]); if (byteEqual != 0) { return byteEqual; } } return 0; }; private Verifier() { } /** * Verify the integrity of a document with respect to a QLDB ledger digest. * * The verification algorithm includes the following steps: * * 1. {@link #buildCandidateDigest(Proof, byte[])} build the candidate digest from the internal hashes * in the {@link Proof}. * 2. Check that the {@code candidateLedgerDigest} is equal to the {@code ledgerDigest}. * * @param documentHash * The hash of the document to be verified. * @param digest * The QLDB ledger digest. This digest should have been retrieved using * {@link com.amazonaws.services.qldb.AmazonQLDB#getDigest} * @param proofBlob * The ion encoded bytes representing the {@link Proof} associated with the supplied * {@code digestTipAddress} and {@code address} retrieved using * {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}. * @return {@code true} if the record is verified or {@code false} if it is not verified. */ public static boolean verify( final byte[] documentHash, final byte[] digest, final String proofBlob ) { Proof proof = Proof.fromBlob(proofBlob); byte[] candidateDigest = buildCandidateDigest(proof, documentHash); return Arrays.equals(digest, candidateDigest); } /** * Build the candidate digest representing the entire ledger from the internal hashes of the {@link Proof}. * * @param proof * A Java representation of {@link Proof} * returned from {@link com.amazonaws.services.qldb.AmazonQLDB#getRevision}. * @param leafHash * Leaf hash to build the candidate digest with. * @return a byte array of the candidate digest. */ private static byte[] buildCandidateDigest(final Proof proof, final byte[] leafHash) { return calculateRootHashFromInternalHashes(proof.getInternalHashes(), leafHash); } /** * Get a new instance of {@link MessageDigest} using the SHA-256 algorithm. * * @return an instance of {@link MessageDigest}. * @throws IllegalStateException if the algorithm is not available on the current JVM. */ static MessageDigest newMessageDigest() { try { return MessageDigest.getInstance("SHA-256"); } catch (NoSuchAlgorithmException e) { log.error("Failed to create SHA-256 MessageDigest", e); throw new IllegalStateException("SHA-256 message digest is unavailable", e); } } /** * Takes two hashes, sorts them, concatenates them, and then returns the * hash of the concatenated array. * * @param h1 * Byte array containing one of the hashes to compare. * @param h2 * Byte array containing one of the hashes to compare. * @return the concatenated array of hashes. */ public static byte[] dot(final byte[] h1, final byte[] h2) { if (h1.length == 0) { return h2; } if (h2.length == 0) { return h1; } byte[] concatenated = new byte[h1.length + h2.length]; if (hashComparator.compare(h1, h2) < 0) { System.arraycopy(h1, 0, concatenated, 0, h1.length); System.arraycopy(h2, 0, concatenated, h1.length, h2.length); } else { System.arraycopy(h2, 0, concatenated, 0, h2.length); System.arraycopy(h1, 0, concatenated, h2.length, h1.length); } MessageDigest messageDigest = newMessageDigest(); messageDigest.update(concatenated); return messageDigest.digest(); } /** * Starting with the provided {@code leafHash} combined with the provided {@code internalHashes} * pairwise until only the root hash remains. * * @param internalHashes * Internal hashes of Merkle tree. * @param leafHash * Leaf hashes of Merkle tree. * @return the root hash. */ private static byte[] calculateRootHashFromInternalHashes(final List internalHashes, final byte[] leafHash) { return internalHashes.stream().reduce(leafHash, Verifier::dot); } /** * Flip a single random bit in the given byte array. This method is used to demonstrate * QLDB's verification features. * * @param original * The original byte array. * @return the altered byte array with a single random bit changed. */ public static byte[] flipRandomBit(final byte[] original) { if (original.length == 0) { throw new IllegalArgumentException("Array cannot be empty!"); } int alteredPosition = ThreadLocalRandom.current().nextInt(original.length); int b = ThreadLocalRandom.current().nextInt(UPPER_BOUND); byte[] altered = new byte[original.length]; System.arraycopy(original, 0, altered, 0, original.length); altered[alteredPosition] = (byte) (altered[alteredPosition] ^ (1 << b)); return altered; } public static String toBase64(byte[] arr) { return new String(Base64.encode(arr), StandardCharsets.UTF_8); } /** * Convert a {@link ByteBuffer} into byte array. * * @param buffer * The {@link ByteBuffer} to convert. * @return the converted byte array. */ public static byte[] convertByteBufferToByteArray(final ByteBuffer buffer) { byte[] arr = new byte[buffer.remaining()]; buffer.get(arr); return arr; } /** * Calculates the root hash from a list of hashes that represent the base of a Merkle tree. * * @param hashes * The list of byte arrays representing hashes making up base of a Merkle tree. * @return a byte array that is the root hash of the given list of hashes. */ public static byte[] calculateMerkleTreeRootHash(List hashes) { if (hashes.isEmpty()) { return new byte[0]; } List remaining = combineLeafHashes(hashes); while (remaining.size() > 1) { remaining = combineLeafHashes(remaining); } return remaining.get(0); } private static List combineLeafHashes(List hashes) { List combinedHashes = new ArrayList<>(); Iterator it = hashes.stream().iterator(); while (it.hasNext()) { byte[] left = it.next(); if (it.hasNext()) { byte[] right = it.next(); byte[] combined = dot(left, right); combinedHashes.add(combined); } else { combinedHashes.add(left); } } return combinedHashes; } } ``` ------ 1. Gunakan dua `.java` file (`GetDigest.java`dan`GetRevision.java`) untuk melakukan langkah-langkah berikut: + Minta intisari baru dari `vehicle-registration` buku besar. + Minta bukti untuk setiap revisi dokumen dari `VehicleRegistration` tabel. + Verifikasi revisi menggunakan intisari dan bukti yang dikembalikan dengan menghitung ulang intisari. `GetDigest.java`Program ini berisi kode berikut. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.model.GetDigestRequest; import com.amazonaws.services.qldb.model.GetDigestResult; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.tutorial.qldb.QldbStringUtils; /** * This is an example for retrieving the digest of a particular ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class GetDigest { public static final Logger log = LoggerFactory.getLogger(GetDigest.class); public static AmazonQLDB client = CreateLedger.getClient(); private GetDigest() { } /** * Calls {@link #getDigest(String)} for a ledger. * * @param args * Arbitrary command-line arguments. * @throws Exception if failed to get a ledger digest. */ public static void main(final String... args) throws Exception { try { getDigest(Constants.LEDGER_NAME); } catch (Exception e) { log.error("Unable to get a ledger digest!", e); throw e; } } /** * Get the digest for the specified ledger. * * @param ledgerName * The ledger to get digest from. * @return {@link GetDigestResult}. */ public static GetDigestResult getDigest(final String ledgerName) { log.info("Let's get the current digest of the ledger named {}.", ledgerName); GetDigestRequest request = new GetDigestRequest() .withName(ledgerName); GetDigestResult result = client.getDigest(request); log.info("Success. LedgerDigest: {}.", QldbStringUtils.toUnredactedString(result)); return result; } } ``` **catatan** Gunakan `getDigest` metode ini untuk meminta intisari yang mencakup *ujung* jurnal saat ini di buku besar Anda. Tip jurnal mengacu pada blok komitmen terbaru pada saat QLDB menerima permintaan Anda. `GetRevision.java`Program ini berisi kode berikut. ------ #### [ 2.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonReader; import com.amazon.ion.IonStruct; import com.amazon.ion.IonSystem; import com.amazon.ion.IonValue; import com.amazon.ion.IonWriter; import com.amazon.ion.system.IonReaderBuilder; import com.amazon.ion.system.IonSystemBuilder; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.model.GetDigestResult; import com.amazonaws.services.qldb.model.GetRevisionRequest; import com.amazonaws.services.qldb.model.GetRevisionResult; import com.amazonaws.services.qldb.model.ValueHolder; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.QldbDriver; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; import software.amazon.qldb.tutorial.qldb.BlockAddress; import software.amazon.qldb.tutorial.qldb.QldbRevision; import software.amazon.qldb.tutorial.qldb.QldbStringUtils; /** * Verify the integrity of a document revision in a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class GetRevision { public static final Logger log = LoggerFactory.getLogger(GetRevision.class); public static AmazonQLDB client = CreateLedger.getClient(); private static final IonSystem SYSTEM = IonSystemBuilder.standard().build(); private GetRevision() { } public static void main(String... args) throws Exception { final String vin = SampleData.REGISTRATIONS.get(0).getVin(); verifyRegistration(ConnectToLedger.getDriver(), Constants.LEDGER_NAME, vin); } /** * Verify each version of the registration for the given VIN. * * @param driver * A QLDB driver. * @param ledgerName * The ledger to get digest from. * @param vin * VIN to query the revision history of a specific registration with. * @throws Exception if failed to verify digests. * @throws AssertionError if document revision verification failed. */ public static void verifyRegistration(final QldbDriver driver, final String ledgerName, final String vin) throws Exception { log.info(String.format("Let's verify the registration with VIN=%s, in ledger=%s.", vin, ledgerName)); try { log.info("First, let's get a digest."); GetDigestResult digestResult = GetDigest.getDigest(ledgerName); ValueHolder digestTipAddress = digestResult.getDigestTipAddress(); byte[] digestBytes = Verifier.convertByteBufferToByteArray(digestResult.getDigest()); log.info("Got a ledger digest. Digest end address={}, digest={}.", QldbStringUtils.toUnredactedString(digestTipAddress), Verifier.toBase64(digestBytes)); log.info(String.format("Next, let's query the registration with VIN=%s. " + "Then we can verify each version of the registration.", vin)); List documentsWithMetadataList = new ArrayList<>(); driver.execute(txn -> { documentsWithMetadataList.addAll(queryRegistrationsByVin(txn, vin)); }); log.info("Registrations queried successfully!"); log.info(String.format("Found %s revisions of the registration with VIN=%s.", documentsWithMetadataList.size(), vin)); for (IonStruct ionStruct : documentsWithMetadataList) { QldbRevision document = QldbRevision.fromIon(ionStruct); log.info(String.format("Let's verify the document: %s", document)); log.info("Let's get a proof for the document."); GetRevisionResult proofResult = getRevision( ledgerName, document.getMetadata().getId(), digestTipAddress, document.getBlockAddress() ); final IonValue proof = Constants.MAPPER.writeValueAsIonValue(proofResult.getProof()); final IonReader reader = IonReaderBuilder.standard().build(proof); reader.next(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); IonWriter writer = SYSTEM.newBinaryWriter(baos); writer.writeValue(reader); writer.close(); baos.flush(); baos.close(); byte[] byteProof = baos.toByteArray(); log.info(String.format("Got back a proof: %s", Verifier.toBase64(byteProof))); boolean verified = Verifier.verify( document.getHash(), digestBytes, proofResult.getProof().getIonText() ); if (!verified) { throw new AssertionError("Document revision is not verified!"); } else { log.info("Success! The document is verified"); } byte[] alteredDigest = Verifier.flipRandomBit(digestBytes); log.info(String.format("Flipping one bit in the digest and assert that the document is NOT verified. " + "The altered digest is: %s", Verifier.toBase64(alteredDigest))); verified = Verifier.verify( document.getHash(), alteredDigest, proofResult.getProof().getIonText() ); if (verified) { throw new AssertionError("Expected document to not be verified against altered digest."); } else { log.info("Success! As expected flipping a bit in the digest causes verification to fail."); } byte[] alteredDocumentHash = Verifier.flipRandomBit(document.getHash()); log.info(String.format("Flipping one bit in the document's hash and assert that it is NOT verified. " + "The altered document hash is: %s.", Verifier.toBase64(alteredDocumentHash))); verified = Verifier.verify( alteredDocumentHash, digestBytes, proofResult.getProof().getIonText() ); if (verified) { throw new AssertionError("Expected altered document hash to not be verified against digest."); } else { log.info("Success! As expected flipping a bit in the document hash causes verification to fail."); } } } catch (Exception e) { log.error("Failed to verify digests.", e); throw e; } log.info(String.format("Finished verifying the registration with VIN=%s in ledger=%s.", vin, ledgerName)); } /** * Get the revision of a particular document specified by the given document ID and block address. * * @param ledgerName * Name of the ledger containing the document. * @param documentId * Unique ID for the document to be verified, contained in the committed view of the document. * @param digestTipAddress * The latest block location covered by the digest. * @param blockAddress * The location of the block to request. * @return the requested revision. */ public static GetRevisionResult getRevision(final String ledgerName, final String documentId, final ValueHolder digestTipAddress, final BlockAddress blockAddress) { try { GetRevisionRequest request = new GetRevisionRequest() .withName(ledgerName) .withDigestTipAddress(digestTipAddress) .withBlockAddress(new ValueHolder().withIonText(Constants.MAPPER.writeValueAsIonValue(blockAddress) .toString())) .withDocumentId(documentId); return client.getRevision(request); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Query the registration history for the given VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * The unique VIN to query. * @return a list of {@link IonStruct} representing the registration history. * @throws IllegalStateException if failed to convert parameters into {@link IonValue} */ public static List queryRegistrationsByVin(final TransactionExecutor txn, final String vin) { log.info(String.format("Let's query the 'VehicleRegistration' table for VIN: %s...", vin)); log.info("Let's query the 'VehicleRegistration' table for VIN: {}...", vin); final String query = String.format("SELECT * FROM _ql_committed_%s WHERE data.VIN = ?", Constants.VEHICLE_REGISTRATION_TABLE_NAME); try { final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin)); final Result result = txn.execute(query, parameters); List list = ScanTable.toIonStructs(result); log.info(String.format("Found %d document(s)!", list.size())); return list; } catch (IOException ioe) { throw new IllegalStateException(ioe); } } } ``` ------ #### [ 1.x ] ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazon.ion.IonReader; import com.amazon.ion.IonStruct; import com.amazon.ion.IonValue; import com.amazon.ion.IonWriter; import com.amazon.ion.system.IonReaderBuilder; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.model.GetDigestResult; import com.amazonaws.services.qldb.model.GetRevisionRequest; import com.amazonaws.services.qldb.model.GetRevisionResult; import com.amazonaws.services.qldb.model.ValueHolder; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.QldbSession; import software.amazon.qldb.Result; import software.amazon.qldb.TransactionExecutor; import software.amazon.qldb.tutorial.model.SampleData; import software.amazon.qldb.tutorial.qldb.BlockAddress; import software.amazon.qldb.tutorial.qldb.QldbRevision; import software.amazon.qldb.tutorial.qldb.QldbStringUtils; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.List; /** * Verify the integrity of a document revision in a QLDB ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class GetRevision { public static final Logger log = LoggerFactory.getLogger(GetRevision.class); public static AmazonQLDB client = CreateLedger.getClient(); private GetRevision() { } public static void main(String... args) throws Exception { final String vin = SampleData.REGISTRATIONS.get(0).getVin(); try (QldbSession qldbSession = ConnectToLedger.createQldbSession()) { verifyRegistration(qldbSession, Constants.LEDGER_NAME, vin); } } /** * Verify each version of the registration for the given VIN. * * @param qldbSession * A QLDB session. * @param ledgerName * The ledger to get digest from. * @param vin * VIN to query the revision history of a specific registration with. * @throws Exception if failed to verify digests. * @throws AssertionError if document revision verification failed. */ public static void verifyRegistration(final QldbSession qldbSession, final String ledgerName, final String vin) throws Exception { log.info(String.format("Let's verify the registration with VIN=%s, in ledger=%s.", vin, ledgerName)); try { log.info("First, let's get a digest."); GetDigestResult digestResult = GetDigest.getDigest(ledgerName); ValueHolder digestTipAddress = digestResult.getDigestTipAddress(); byte[] digestBytes = Verifier.convertByteBufferToByteArray(digestResult.getDigest()); log.info("Got a ledger digest. Digest end address={}, digest={}.", QldbStringUtils.toUnredactedString(digestTipAddress), Verifier.toBase64(digestBytes)); log.info(String.format("Next, let's query the registration with VIN=%s. " + "Then we can verify each version of the registration.", vin)); List documentsWithMetadataList = new ArrayList<>(); qldbSession.execute(txn -> { documentsWithMetadataList.addAll(queryRegistrationsByVin(txn, vin)); }, (retryAttempt) -> log.info("Retrying due to OCC conflict...")); log.info("Registrations queried successfully!"); log.info(String.format("Found %s revisions of the registration with VIN=%s.", documentsWithMetadataList.size(), vin)); for (IonStruct ionStruct : documentsWithMetadataList) { QldbRevision document = QldbRevision.fromIon(ionStruct); log.info(String.format("Let's verify the document: %s", document)); log.info("Let's get a proof for the document."); GetRevisionResult proofResult = getRevision( ledgerName, document.getMetadata().getId(), digestTipAddress, document.getBlockAddress() ); final IonValue proof = Constants.MAPPER.writeValueAsIonValue(proofResult.getProof()); final IonReader reader = IonReaderBuilder.standard().build(proof); reader.next(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); IonWriter writer = Constants.SYSTEM.newBinaryWriter(baos); writer.writeValue(reader); writer.close(); baos.flush(); baos.close(); byte[] byteProof = baos.toByteArray(); log.info(String.format("Got back a proof: %s", Verifier.toBase64(byteProof))); boolean verified = Verifier.verify( document.getHash(), digestBytes, proofResult.getProof().getIonText() ); if (!verified) { throw new AssertionError("Document revision is not verified!"); } else { log.info("Success! The document is verified"); } byte[] alteredDigest = Verifier.flipRandomBit(digestBytes); log.info(String.format("Flipping one bit in the digest and assert that the document is NOT verified. " + "The altered digest is: %s", Verifier.toBase64(alteredDigest))); verified = Verifier.verify( document.getHash(), alteredDigest, proofResult.getProof().getIonText() ); if (verified) { throw new AssertionError("Expected document to not be verified against altered digest."); } else { log.info("Success! As expected flipping a bit in the digest causes verification to fail."); } byte[] alteredDocumentHash = Verifier.flipRandomBit(document.getHash()); log.info(String.format("Flipping one bit in the document's hash and assert that it is NOT verified. " + "The altered document hash is: %s.", Verifier.toBase64(alteredDocumentHash))); verified = Verifier.verify( alteredDocumentHash, digestBytes, proofResult.getProof().getIonText() ); if (verified) { throw new AssertionError("Expected altered document hash to not be verified against digest."); } else { log.info("Success! As expected flipping a bit in the document hash causes verification to fail."); } } } catch (Exception e) { log.error("Failed to verify digests.", e); throw e; } log.info(String.format("Finished verifying the registration with VIN=%s in ledger=%s.", vin, ledgerName)); } /** * Get the revision of a particular document specified by the given document ID and block address. * * @param ledgerName * Name of the ledger containing the document. * @param documentId * Unique ID for the document to be verified, contained in the committed view of the document. * @param digestTipAddress * The latest block location covered by the digest. * @param blockAddress * The location of the block to request. * @return the requested revision. */ public static GetRevisionResult getRevision(final String ledgerName, final String documentId, final ValueHolder digestTipAddress, final BlockAddress blockAddress) { try { GetRevisionRequest request = new GetRevisionRequest() .withName(ledgerName) .withDigestTipAddress(digestTipAddress) .withBlockAddress(new ValueHolder().withIonText(Constants.MAPPER.writeValueAsIonValue(blockAddress) .toString())) .withDocumentId(documentId); return client.getRevision(request); } catch (IOException ioe) { throw new IllegalStateException(ioe); } } /** * Query the registration history for the given VIN. * * @param txn * The {@link TransactionExecutor} for lambda execute. * @param vin * The unique VIN to query. * @return a list of {@link IonStruct} representing the registration history. * @throws IllegalStateException if failed to convert parameters into {@link IonValue} */ public static List queryRegistrationsByVin(final TransactionExecutor txn, final String vin) { log.info(String.format("Let's query the 'VehicleRegistration' table for VIN: %s...", vin)); log.info("Let's query the 'VehicleRegistration' table for VIN: {}...", vin); final String query = String.format("SELECT * FROM _ql_committed_%s WHERE data.VIN = ?", Constants.VEHICLE_REGISTRATION_TABLE_NAME); try { final List parameters = Collections.singletonList(Constants.MAPPER.writeValueAsIonValue(vin)); final Result result = txn.execute(query, parameters); List list = ScanTable.toIonStructs(result); log.info(String.format("Found %d document(s)!", list.size())); return list; } catch (IOException ioe) { throw new IllegalStateException(ioe); } } } ``` ------ **catatan** Setelah `getRevision` metode mengembalikan bukti untuk revisi dokumen yang ditentukan, program ini menggunakan API sisi klien untuk memverifikasi revisi tersebut. Untuk ikhtisar algoritma yang digunakan oleh API ini, lihat[Menggunakan bukti untuk menghitung ulang intisari Anda](verification.results.md#verification.results.recalc). 1. Kompilasi dan jalankan `GetRevision.java` program untuk memverifikasi `VehicleRegistration` dokumen secara kriptografi dengan VIN. `1N4AL11D75C109151` Untuk mengekspor dan memvalidasi data jurnal dalam `vehicle-registration` buku besar, lanjutkan ke. [Langkah 8: Ekspor dan validasi data jurnal dalam buku besar](getting-started.java.step-8.md) # Langkah 8: Ekspor dan validasi data jurnal dalam buku besar **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Di Amazon QLDB, Anda dapat mengakses konten jurnal di buku besar Anda untuk berbagai tujuan seperti retensi data, analitik, dan audit. Untuk informasi selengkapnya, lihat [Mengekspor data jurnal dari Amazon QLDB](export-journal.md). Pada langkah ini, Anda mengekspor [blok jurnal](journal-contents.md) dari `vehicle-registration` buku besar ke bucket Amazon S3. Kemudian, Anda menggunakan data yang diekspor untuk memvalidasi rantai hash antara blok jurnal dan komponen hash individu dalam setiap blok. Entitas utama AWS Identity and Access Management (IAM) yang Anda gunakan harus memiliki izin IAM yang memadai untuk membuat bucket Amazon S3 di bucket Anda. Akun AWS Untuk selengkapnya, lihat [Kebijakan dan Izin di Amazon](https://docs.aws.amazon.com/AmazonS3/latest/userguide/access-policy-language-overview.html) S3 di Panduan Pengguna *Amazon S3*. Anda juga harus memiliki izin untuk membuat peran IAM dengan kebijakan izin terlampir yang memungkinkan QLDB menulis objek ke dalam bucket Amazon S3 Anda. Untuk mempelajari lebih lanjut, lihat [Izin yang diperlukan untuk mengakses sumber daya IAM](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_permissions-required.html) di Panduan Pengguna *IAM*. **Mengekspor dan memvalidasi data jurnal** 1. Tinjau file berikut (`JournalBlock.java`), yang mewakili blok jurnal dan isi datanya. Ini termasuk metode bernama `verifyBlockHash()` yang menunjukkan bagaimana menghitung setiap komponen individu dari hash blok. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial.qldb; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.annotation.JsonSerialize; import com.fasterxml.jackson.dataformat.ion.IonTimestampSerializers; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.tutorial.Constants; import software.amazon.qldb.tutorial.Verifier; import java.io.IOException; import java.nio.ByteBuffer; import java.util.Arrays; import java.util.Date; import java.util.HashSet; import java.util.List; import java.util.Set; import java.util.stream.Collectors; import static java.nio.ByteBuffer.wrap; /** * Represents a JournalBlock that was recorded after executing a transaction * in the ledger. */ public final class JournalBlock { private static final Logger log = LoggerFactory.getLogger(JournalBlock.class); private BlockAddress blockAddress; private String transactionId; @JsonSerialize(using = IonTimestampSerializers.IonTimestampJavaDateSerializer.class) private Date blockTimestamp; private byte[] blockHash; private byte[] entriesHash; private byte[] previousBlockHash; private byte[][] entriesHashList; private TransactionInfo transactionInfo; private RedactionInfo redactionInfo; private List revisions; @JsonCreator public JournalBlock(@JsonProperty("blockAddress") final BlockAddress blockAddress, @JsonProperty("transactionId") final String transactionId, @JsonProperty("blockTimestamp") final Date blockTimestamp, @JsonProperty("blockHash") final byte[] blockHash, @JsonProperty("entriesHash") final byte[] entriesHash, @JsonProperty("previousBlockHash") final byte[] previousBlockHash, @JsonProperty("entriesHashList") final byte[][] entriesHashList, @JsonProperty("transactionInfo") final TransactionInfo transactionInfo, @JsonProperty("redactionInfo") final RedactionInfo redactionInfo, @JsonProperty("revisions") final List revisions) { this.blockAddress = blockAddress; this.transactionId = transactionId; this.blockTimestamp = blockTimestamp; this.blockHash = blockHash; this.entriesHash = entriesHash; this.previousBlockHash = previousBlockHash; this.entriesHashList = entriesHashList; this.transactionInfo = transactionInfo; this.redactionInfo = redactionInfo; this.revisions = revisions; } public BlockAddress getBlockAddress() { return blockAddress; } public String getTransactionId() { return transactionId; } public Date getBlockTimestamp() { return blockTimestamp; } public byte[][] getEntriesHashList() { return entriesHashList; } public TransactionInfo getTransactionInfo() { return transactionInfo; } public RedactionInfo getRedactionInfo() { return redactionInfo; } public List getRevisions() { return revisions; } public byte[] getEntriesHash() { return entriesHash; } public byte[] getBlockHash() { return blockHash; } public byte[] getPreviousBlockHash() { return previousBlockHash; } @Override public String toString() { return "JournalBlock{" + "blockAddress=" + blockAddress + ", transactionId='" + transactionId + '\'' + ", blockTimestamp=" + blockTimestamp + ", blockHash=" + Arrays.toString(blockHash) + ", entriesHash=" + Arrays.toString(entriesHash) + ", previousBlockHash=" + Arrays.toString(previousBlockHash) + ", entriesHashList=" + Arrays.toString(entriesHashList) + ", transactionInfo=" + transactionInfo + ", redactionInfo=" + redactionInfo + ", revisions=" + revisions + '}'; } @Override public boolean equals(final Object o) { if (this == o) { return true; } if (!(o instanceof JournalBlock)) { return false; } final JournalBlock that = (JournalBlock) o; if (!getBlockAddress().equals(that.getBlockAddress())) { return false; } if (!getTransactionId().equals(that.getTransactionId())) { return false; } if (!getBlockTimestamp().equals(that.getBlockTimestamp())) { return false; } if (!Arrays.equals(getBlockHash(), that.getBlockHash())) { return false; } if (!Arrays.equals(getEntriesHash(), that.getEntriesHash())) { return false; } if (!Arrays.equals(getPreviousBlockHash(), that.getPreviousBlockHash())) { return false; } if (!Arrays.deepEquals(getEntriesHashList(), that.getEntriesHashList())) { return false; } if (!getTransactionInfo().equals(that.getTransactionInfo())) { return false; } if (getRedactionInfo() != null ? !getRedactionInfo().equals(that.getRedactionInfo()) : that.getRedactionInfo() != null) { return false; } return getRevisions() != null ? getRevisions().equals(that.getRevisions()) : that.getRevisions() == null; } @Override public int hashCode() { int result = getBlockAddress().hashCode(); result = 31 * result + getTransactionId().hashCode(); result = 31 * result + getBlockTimestamp().hashCode(); result = 31 * result + Arrays.hashCode(getBlockHash()); result = 31 * result + Arrays.hashCode(getEntriesHash()); result = 31 * result + Arrays.hashCode(getPreviousBlockHash()); result = 31 * result + Arrays.deepHashCode(getEntriesHashList()); result = 31 * result + getTransactionInfo().hashCode(); result = 31 * result + (getRedactionInfo() != null ? getRedactionInfo().hashCode() : 0); result = 31 * result + (getRevisions() != null ? getRevisions().hashCode() : 0); return result; } /** * This method validates that the hashes of the components of a journal block make up the block * hash that is provided with the block itself. * * The components that contribute to the hash of the journal block consist of the following: * - user transaction information (contained in [transactionInfo]) * - user redaction information (contained in [redactionInfo]) * - user revisions (contained in [revisions]) * - hashes of internal-only system metadata (contained in [revisions] and in [entriesHashList]) * - the previous block hash * * If any of the computed hashes of user information cannot be validated or any of the system * hashes do not result in the correct computed values, this method will throw an IllegalArgumentException. * * Internal-only system metadata is represented by its hash, and can be present in the form of certain * items in the [revisions] list that only contain a hash and no user data, as well as some hashes * in [entriesHashList]. * * To validate that the hashes of the user data are valid components of the [blockHash], this method * performs the following steps: * * 1. Compute the hash of the [transactionInfo] and validate that it is included in the [entriesHashList]. * 2. Compute the hash of the [redactionInfo], if present, and validate that it is included in the [entriesHashList]. * 3. Validate the hash of each user revision was correctly computed and matches the hash published * with that revision. * 4. Compute the hash of the [revisions] by treating the revision hashes as the leaf nodes of a Merkle tree * and calculating the root hash of that tree. Then validate that hash is included in the [entriesHashList]. * 5. Compute the hash of the [entriesHashList] by treating the hashes as the leaf nodes of a Merkle tree * and calculating the root hash of that tree. Then validate that hash matches [entriesHash]. * 6. Finally, compute the block hash by computing the hash resulting from concatenating the [entriesHash] * and previous block hash, and validate that the result matches the [blockHash] provided by QLDB with the block. * * This method is called by ValidateQldbHashChain::verify for each journal block to validate its * contents before verifying that the hash chain between consecutive blocks is correct. */ public void verifyBlockHash() { Set entriesHashSet = new HashSet<>(); Arrays.stream(entriesHashList).forEach(hash -> entriesHashSet.add(wrap(hash).asReadOnlyBuffer())); byte[] computedTransactionInfoHash = computeTransactionInfoHash(); if (!entriesHashSet.contains(wrap(computedTransactionInfoHash).asReadOnlyBuffer())) { throw new IllegalArgumentException( "Block transactionInfo hash is not contained in the QLDB block entries hash list."); } if (redactionInfo != null) { byte[] computedRedactionInfoHash = computeRedactionInfoHash(); if (!entriesHashSet.contains(wrap(computedRedactionInfoHash).asReadOnlyBuffer())) { throw new IllegalArgumentException( "Block redactionInfo hash is not contained in the QLDB block entries hash list."); } } if (revisions != null) { revisions.forEach(QldbRevision::verifyRevisionHash); byte[] computedRevisionsHash = computeRevisionsHash(); if (!entriesHashSet.contains(wrap(computedRevisionsHash).asReadOnlyBuffer())) { throw new IllegalArgumentException( "Block revisions list hash is not contained in the QLDB block entries hash list."); } } byte[] computedEntriesHash = computeEntriesHash(); if (!Arrays.equals(computedEntriesHash, entriesHash)) { throw new IllegalArgumentException("Computed entries hash does not match entries hash provided in the block."); } byte[] computedBlockHash = Verifier.dot(computedEntriesHash, previousBlockHash); if (!Arrays.equals(computedBlockHash, blockHash)) { throw new IllegalArgumentException("Computed block hash does not match block hash provided in the block."); } } private byte[] computeTransactionInfoHash() { try { return QldbIonUtils.hashIonValue(Constants.MAPPER.writeValueAsIonValue(transactionInfo)); } catch (IOException e) { throw new IllegalArgumentException("Could not compute transactionInfo hash to verify block hash.", e); } } private byte[] computeRedactionInfoHash() { try { return QldbIonUtils.hashIonValue(Constants.MAPPER.writeValueAsIonValue(redactionInfo)); } catch (IOException e) { throw new IllegalArgumentException("Could not compute redactionInfo hash to verify block hash.", e); } } private byte[] computeRevisionsHash() { return Verifier.calculateMerkleTreeRootHash(revisions.stream().map(QldbRevision::getHash).collect(Collectors.toList())); } private byte[] computeEntriesHash() { return Verifier.calculateMerkleTreeRootHash(Arrays.asList(entriesHashList)); } } ``` 1. Kompilasi dan jalankan program berikut (`ValidateQldbHashChain.java`) untuk melakukan langkah-langkah berikut: 1. Ekspor blok jurnal dari `vehicle-registration` buku besar ke bucket Amazon S3 **qldb-tutorial-journal-export-*111122223333*** bernama (ganti dengan nomor Akun AWS Anda). 1. Validasi komponen hash individual dalam setiap blok dengan memanggil. `verifyBlockHash()` 1. Validasi rantai hash antara blok jurnal. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.services.qldb.model.ExportJournalToS3Result; import com.amazonaws.services.qldb.model.S3EncryptionConfiguration; import com.amazonaws.services.qldb.model.S3ObjectEncryptionType; import com.amazonaws.services.s3.AmazonS3ClientBuilder; import java.time.Instant; import java.util.Arrays; import java.util.List; import com.amazonaws.services.securitytoken.AWSSecurityTokenServiceClientBuilder; import com.amazonaws.services.securitytoken.model.GetCallerIdentityRequest; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import software.amazon.qldb.tutorial.qldb.JournalBlock; /** * Validate the hash chain of a QLDB ledger by stepping through its S3 export. * * This code accepts an exportId as an argument, if exportId is passed the code * will use that or request QLDB to generate a new export to perform QLDB hash * chain validation. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class ValidateQldbHashChain { public static final Logger log = LoggerFactory.getLogger(ValidateQldbHashChain.class); private static final int TIME_SKEW = 20; private ValidateQldbHashChain() { } /** * Export journal contents to a S3 bucket. * * @return the ExportId of the journal export. * @throws InterruptedException if the thread is interrupted while waiting for export to complete. */ private static String createExport() throws InterruptedException { String accountId = AWSSecurityTokenServiceClientBuilder.defaultClient() .getCallerIdentity(new GetCallerIdentityRequest()).getAccount(); String bucketName = Constants.JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX + "-" + accountId; String prefix = Constants.LEDGER_NAME + "-" + Instant.now().getEpochSecond() + "/"; S3EncryptionConfiguration encryptionConfiguration = new S3EncryptionConfiguration() .withObjectEncryptionType(S3ObjectEncryptionType.SSE_S3); ExportJournalToS3Result exportJournalToS3Result = ExportJournal.createJournalExportAndAwaitCompletion(Constants.LEDGER_NAME, bucketName, prefix, null, encryptionConfiguration, ExportJournal.DEFAULT_EXPORT_TIMEOUT_MS); return exportJournalToS3Result.getExportId(); } /** * Validates that the chain hash on the {@link JournalBlock} is valid. * * @param journalBlocks * {@link JournalBlock} containing hashes to validate. * @throws IllegalStateException if previous block hash does not match. */ public static void verify(final List journalBlocks) { if (journalBlocks.size() == 0) { return; } journalBlocks.stream().reduce(null, (previousJournalBlock, journalBlock) -> { journalBlock.verifyBlockHash(); if (previousJournalBlock == null) { return journalBlock; } if (!Arrays.equals(previousJournalBlock.getBlockHash(), journalBlock.getPreviousBlockHash())) { throw new IllegalStateException("Previous block hash doesn't match."); } byte[] blockHash = Verifier.dot(journalBlock.getEntriesHash(), previousJournalBlock.getBlockHash()); if (!Arrays.equals(blockHash, journalBlock.getBlockHash())) { throw new IllegalStateException("Block hash doesn't match entriesHash dot previousBlockHash, the chain is " + "broken."); } return journalBlock; }); } public static void main(final String... args) throws InterruptedException { try { String exportId; if (args.length == 1) { exportId = args[0]; log.info("Validating QLDB hash chain for exportId: " + exportId); } else { log.info("Requesting QLDB to create an export."); exportId = createExport(); } List journalBlocks = JournalS3ExportReader.readExport(DescribeJournalExport.describeExport(Constants.LEDGER_NAME, exportId), AmazonS3ClientBuilder.defaultClient()); verify(journalBlocks); } catch (Exception e) { log.error("Unable to perform hash chain verification.", e); throw e; } } } ``` Jika Anda tidak perlu lagi menggunakan `vehicle-registration` buku besar, lanjutkan ke[Langkah 9 (opsional): Bersihkan sumber daya](getting-started.java.step-9.md). # Langkah 9 (opsional): Bersihkan sumber daya **penting** Pemberitahuan akhir dukungan: Pelanggan yang ada akan dapat menggunakan Amazon QLDB hingga akhir dukungan pada 07/31/2025. Untuk detail selengkapnya, lihat [Memigrasi Buku Besar QLDB Amazon ke Amazon](https://aws.amazon.com/blogs/database/migrate-an-amazon-qldb-ledger-to-amazon-aurora-postgresql/) Aurora PostgreSQL. Anda dapat terus menggunakan `vehicle-registration` buku besar. Namun, jika Anda tidak lagi membutuhkannya, Anda harus menghapusnya. **Untuk menghapus buku besar** 1. Kompilasi dan jalankan program berikut (`DeleteLedger.java`) untuk menghapus `vehicle-registration` buku besar Anda dan semua isinya. ``` /* * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: MIT-0 * * Permission is hereby granted, free of charge, to any person obtaining a copy of this * software and associated documentation files (the "Software"), to deal in the Software * without restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package software.amazon.qldb.tutorial; import com.amazonaws.services.qldb.AmazonQLDB; import com.amazonaws.services.qldb.model.DeleteLedgerRequest; import com.amazonaws.services.qldb.model.DeleteLedgerResult; import com.amazonaws.services.qldb.model.ResourceNotFoundException; import com.amazonaws.services.qldb.model.UpdateLedgerRequest; import com.amazonaws.services.qldb.model.UpdateLedgerResult; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Delete a ledger. * * This code expects that you have AWS credentials setup per: * http://docs.aws.amazon.com/java-sdk/latest/developer-guide/setup-credentials.html */ public final class DeleteLedger { public static final Logger log = LoggerFactory.getLogger(DeleteLedger.class); public static final Long LEDGER_DELETION_POLL_PERIOD_MS = 20_000L; public static AmazonQLDB client = CreateLedger.getClient(); private DeleteLedger() { } public static void main(String... args) throws Exception { try { setDeletionProtection(Constants.LEDGER_NAME, false); delete(Constants.LEDGER_NAME); waitForDeleted(Constants.LEDGER_NAME); } catch (Exception e) { log.error("Unable to delete the ledger.", e); throw e; } } /** * Send a request to the QLDB database to delete the specified ledger. * * @param ledgerName * Name of the ledger to be deleted. * @return DeleteLedgerResult. */ public static DeleteLedgerResult delete(final String ledgerName) { log.info("Attempting to delete the ledger with name: {}...", ledgerName); DeleteLedgerRequest request = new DeleteLedgerRequest().withName(ledgerName); DeleteLedgerResult result = client.deleteLedger(request); log.info("Success."); return result; } /** * Wait for the ledger to be deleted. * * @param ledgerName * Name of the ledger being deleted. * @throws InterruptedException if thread is being interrupted. */ public static void waitForDeleted(final String ledgerName) throws InterruptedException { log.info("Waiting for the ledger to be deleted..."); while (true) { try { DescribeLedger.describe(ledgerName); log.info("The ledger is still being deleted. Please wait..."); Thread.sleep(LEDGER_DELETION_POLL_PERIOD_MS); } catch (ResourceNotFoundException ex) { log.info("Success. The ledger is deleted."); break; } } } public static UpdateLedgerResult setDeletionProtection(String ledgerName, boolean deletionProtection) { log.info("Let's set deletionProtection to {} for the ledger with name {}", deletionProtection, ledgerName); UpdateLedgerRequest request = new UpdateLedgerRequest() .withName(ledgerName) .withDeletionProtection(deletionProtection); UpdateLedgerResult result = client.updateLedger(request); log.info("Success. Ledger updated: {}", result); return result; } } ``` **catatan** Jika proteksi penghapusan diaktifkan untuk buku besar Anda, Anda harus menonaktifkannya terlebih dahulu sebelum dapat menghapus buku besar menggunakan QLDB API. 1. Jika Anda mengekspor data jurnal pada [langkah sebelumnya](getting-started.java.step-8.md) dan tidak lagi membutuhkannya, gunakan konsol Amazon S3 untuk menghapus bucket S3 Anda. Buka konsol Amazon S3 di. [https://console.aws.amazon.com/s3/](https://console.aws.amazon.com/s3/)