

文件 AWS 開發套件範例 GitHub 儲存庫中有更多可用的 [AWS SDK 範例](https://github.com/awsdocs/aws-doc-sdk-examples)。

本文為英文版的機器翻譯版本，如內容有任何歧義或不一致之處，概以英文版為準。

# `StartDBCluster` 搭配 AWS SDK 使用
<a name="neptune_example_neptune_StartDBCluster_section"></a>

下列程式碼範例示範如何使用 `StartDBCluster`。

動作範例是大型程式的程式碼摘錄，必須在內容中執行。您可以在下列程式碼範例的內容中看到此動作：
+  [了解基本概念](neptune_example_neptune_Scenario_section.md) 

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#### [ Java ]

**SDK for Java 2.x**  
 GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/neptune#code-examples)中設定和執行。

```
    /**
     * Starts an Amazon Neptune DB cluster.
     *
     * @param clusterIdentifier the unique identifier of the DB cluster to be stopped
     */
    public CompletableFuture<StartDbClusterResponse> startDBClusterAsync(String clusterIdentifier) {
        StartDbClusterRequest clusterRequest = StartDbClusterRequest.builder()
                .dbClusterIdentifier(clusterIdentifier)
                .build();

        return getAsyncClient().startDBCluster(clusterRequest)
                .whenComplete((response, error) -> {
                    if (error != null) {
                        Throwable cause = error.getCause() != null ? error.getCause() : error;

                        if (cause instanceof ResourceNotFoundException) {
                            throw (ResourceNotFoundException) cause;
                        }

                        throw new RuntimeException("Failed to start DB cluster: " + cause.getMessage(), cause);
                    } else {
                        logger.info("DB Cluster starting: " + clusterIdentifier);
                    }
                });
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [StartDBCluster](https://docs.aws.amazon.com/goto/SdkForJavaV2/neptune-2014-10-31/StartDBCluster)。

------
#### [ Python ]

**適用於 Python 的 SDK (Boto3)**  
 GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/neptune#code-examples)中設定和執行。

```
def start_db_cluster(neptune_client, cluster_identifier: str):
    """
    Starts an Amazon Neptune DB cluster and waits until it reaches 'available'.

    Args:
        neptune_client (boto3.client): The Neptune client.
        cluster_identifier (str): The DB cluster identifier.

    Raises:
        ClientError: Propagates AWS API issues like resource not found.
        RuntimeError: If cluster doesn't reach 'available' within timeout.
    """
    try:
        # Initial wait in case the cluster was just stopped
        time.sleep(30)
        neptune_client.start_db_cluster(DBClusterIdentifier=cluster_identifier)
    except ClientError as err:
        code = err.response["Error"]["Code"]
        message = err.response["Error"]["Message"]

        if code == "AccessDeniedException":
            print("Access denied. Please ensure you have the necessary permissions.")
        else:
            print(f"Couldn't start DB cluster. Here's why: {code}: {message}")
        raise

    start_time = time.time()
    paginator = neptune_client.get_paginator('describe_db_clusters')

    while True:
        try:
            pages = paginator.paginate(DBClusterIdentifier=cluster_identifier)
            clusters = []
            for page in pages:
                clusters.extend(page.get('DBClusters', []))
        except ClientError as err:
            code = err.response["Error"]["Code"]
            message = err.response["Error"]["Message"]

            if code == "DBClusterNotFound":
                print(f"Cluster '{cluster_identifier}' not found while polling. It may have been deleted.")
            else:
                print(f"Couldn't describe DB cluster. Here's why: {code}: {message}")
            raise

        status = clusters[0].get('Status') if clusters else None
        elapsed = time.time() - start_time

        print(f"\rElapsed: {int(elapsed)}s – Cluster status: {status}", end="", flush=True)

        if status and status.lower() == 'available':
            print(f"\n🎉 Cluster '{cluster_identifier}' is available.")
            return

        if elapsed > TIMEOUT_SECONDS:
            raise RuntimeError(f"Timeout waiting for cluster '{cluster_identifier}' to become available.")

        time.sleep(POLL_INTERVAL_SECONDS)
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Python (Boto3) API 參考》**中的 [StartDBCluster](https://docs.aws.amazon.com/goto/boto3/neptune-2014-10-31/StartDBCluster)。

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