

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。

# 使用適用於 Java 2.x 的 SDK 的 Lambda 範例
<a name="java_2_lambda_code_examples"></a>

下列程式碼範例示範如何使用 AWS SDK for Java 2.x 搭配 Lambda 執行動作和實作常見案例。

*基本概念*是程式碼範例，這些範例說明如何在服務內執行基本操作。

*Actions* 是大型程式的程式碼摘錄，必須在內容中執行。雖然動作會告訴您如何呼叫個別服務函數，但您可以在其相關情境中查看內容中的動作。

*案例*是向您展示如何呼叫服務中的多個函數或與其他 AWS 服務組合來完成特定任務的程式碼範例。

*AWS 社群貢獻*是由多個團隊所建立和維護的範例 AWS。若要提供意見回饋，請使用連結儲存庫中提供的機制。

每個範例均包含完整原始碼的連結，您可在連結中找到如何設定和執行內容中程式碼的相關指示。

**Topics**
+ [開始使用](#get_started)
+ [基本概念](#basics)
+ [動作](#actions)
+ [案例](#scenarios)
+ [無伺服器範例](#serverless_examples)
+ [AWS 社群貢獻](#aws_community_contributions)

## 開始使用
<a name="get_started"></a>

### Hello Lambda
<a name="lambda_Hello_java_2_topic"></a>

下列程式碼範例示範如何開始使用 Lambda。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Lists the AWS Lambda functions associated with the current AWS account.
     *
     * @param awsLambda an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service
     *
     * @throws LambdaException if an error occurs while interacting with the AWS Lambda service
     */
    public static void listFunctions(LambdaClient awsLambda) {
        try {
            ListFunctionsResponse functionResult = awsLambda.listFunctions();
            List<FunctionConfiguration> list = functionResult.functions();
            for (FunctionConfiguration config : list) {
                System.out.println("The function name is " + config.functionName());
            }

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [ListFunctions](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/ListFunctions)。

## 基本概念
<a name="basics"></a>

### 了解基本概念
<a name="lambda_Scenario_GettingStartedFunctions_java_2_topic"></a>

以下程式碼範例顯示做法：
+ 建立 IAM 角色和 Lambda 函數，然後上傳處理常式程式碼。
+ 調用具有單一參數的函數並取得結果。
+ 更新函數程式碼並使用環境變數進行設定。
+ 調用具有新參數的函數並取得結果。顯示傳回的執行日誌。
+ 列出您帳戶的函數，然後清理相關資源。

如需詳細資訊，請參閱[使用主控台建立 Lambda 函數](https://docs.aws.amazon.com/lambda/latest/dg/getting-started-create-function.html)。

**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/lambda#code-examples)中設定和執行。

```
/*
 *  Lambda function names appear as:
 *
 *  arn:aws:lambda:us-west-2:335556666777:function:HelloFunction
 *
 *  To find this value, look at the function in the AWS Management Console.
 *
 *  Before running this Java code example, set up your development environment, including your credentials.
 *
 *  For more information, see this documentation topic:
 *
 *  https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 *
 *  This example performs the following tasks:
 *
 * 1. Creates an AWS Lambda function.
 * 2. Gets a specific AWS Lambda function.
 * 3. Lists all Lambda functions.
 * 4. Invokes a Lambda function.
 * 5. Updates the Lambda function code and invokes it again.
 * 6. Updates a Lambda function's configuration value.
 * 7. Deletes a Lambda function.
 */

public class LambdaScenario {
    public static final String DASHES = new String(new char[80]).replace("\0", "-");

    public static void main(String[] args) throws InterruptedException {
        final String usage = """

            Usage:
                <functionName> <role> <handler> <bucketName> <key>\s

            Where:
                functionName - The name of the Lambda function.\s
                role - The AWS Identity and Access Management (IAM) service role that has Lambda permissions.\s
                handler - The fully qualified method name (for example, example.Handler::handleRequest).\s
                bucketName - The Amazon Simple Storage Service (Amazon S3) bucket name that contains the .zip or .jar used to update the Lambda function's code.\s
                key - The Amazon S3 key name that represents the .zip or .jar (for example, LambdaHello-1.0-SNAPSHOT.jar).
                """;

        if (args.length != 5) {
              System.out.println(usage);
              return;
        }

        String functionName = args[0];
        String role = args[1];
        String handler = args[2];
        String bucketName = args[3];
        String key = args[4];
        LambdaClient awsLambda = LambdaClient.builder()
            .build();

        System.out.println(DASHES);
        System.out.println("Welcome to the AWS Lambda Basics scenario.");
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("1. Create an AWS Lambda function.");
        String funArn = createLambdaFunction(awsLambda, functionName, key, bucketName, role, handler);
        System.out.println("The AWS Lambda ARN is " + funArn);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("2. Get the " + functionName + " AWS Lambda function.");
        getFunction(awsLambda, functionName);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("3. List all AWS Lambda functions.");
        listFunctions(awsLambda);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("4. Invoke the Lambda function.");
        System.out.println("*** Sleep for 1 min to get Lambda function ready.");
        Thread.sleep(60000);
        invokeFunction(awsLambda, functionName);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("5. Update the Lambda function code and invoke it again.");
        updateFunctionCode(awsLambda, functionName, bucketName, key);
        System.out.println("*** Sleep for 1 min to get Lambda function ready.");
        Thread.sleep(60000);
        invokeFunction(awsLambda, functionName);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("6. Update a Lambda function's configuration value.");
        updateFunctionConfiguration(awsLambda, functionName, handler);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("7. Delete the AWS Lambda function.");
        LambdaScenario.deleteLambdaFunction(awsLambda, functionName);
        System.out.println(DASHES);

        System.out.println(DASHES);
        System.out.println("The AWS Lambda scenario completed successfully");
        System.out.println(DASHES);
        awsLambda.close();
    }

    /**
     * Creates a new Lambda function in AWS using the AWS Lambda Java API.
     *
     * @param awsLambda    the AWS Lambda client used to interact with the AWS Lambda service
     * @param functionName the name of the Lambda function to create
     * @param key          the S3 key of the function code
     * @param bucketName   the name of the S3 bucket containing the function code
     * @param role         the IAM role to assign to the Lambda function
     * @param handler      the fully qualified class name of the function handler
     * @return the Amazon Resource Name (ARN) of the created Lambda function
     */
    public static String createLambdaFunction(LambdaClient awsLambda,
                                              String functionName,
                                              String key,
                                              String bucketName,
                                              String role,
                                              String handler) {

        try {
            LambdaWaiter waiter = awsLambda.waiter();
            FunctionCode code = FunctionCode.builder()
                .s3Key(key)
                .s3Bucket(bucketName)
                .build();

            CreateFunctionRequest functionRequest = CreateFunctionRequest.builder()
                .functionName(functionName)
                .description("Created by the Lambda Java API")
                .code(code)
                .handler(handler)
                .runtime(Runtime.JAVA17)
                .role(role)
                .build();

            // Create a Lambda function using a waiter
            CreateFunctionResponse functionResponse = awsLambda.createFunction(functionRequest);
            GetFunctionRequest getFunctionRequest = GetFunctionRequest.builder()
                .functionName(functionName)
                .build();
            WaiterResponse<GetFunctionResponse> waiterResponse = waiter.waitUntilFunctionExists(getFunctionRequest);
            waiterResponse.matched().response().ifPresent(System.out::println);
            return functionResponse.functionArn();

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
        return "";
    }

    /**
     * Retrieves information about an AWS Lambda function.
     *
     * @param awsLambda    an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service
     * @param functionName the name of the AWS Lambda function to retrieve information about
     */
    public static void getFunction(LambdaClient awsLambda, String functionName) {
        try {
            GetFunctionRequest functionRequest = GetFunctionRequest.builder()
                .functionName(functionName)
                .build();

            GetFunctionResponse response = awsLambda.getFunction(functionRequest);
            System.out.println("The runtime of this Lambda function is " + response.configuration().runtime());

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

    /**
     * Lists the AWS Lambda functions associated with the current AWS account.
     *
     * @param awsLambda an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service
     *
     * @throws LambdaException if an error occurs while interacting with the AWS Lambda service
     */
    public static void listFunctions(LambdaClient awsLambda) {
        try {
            ListFunctionsResponse functionResult = awsLambda.listFunctions();
            List<FunctionConfiguration> list = functionResult.functions();
            for (FunctionConfiguration config : list) {
                System.out.println("The function name is " + config.functionName());
            }

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

    /**
     * Invokes a specific AWS Lambda function.
     *
     * @param awsLambda    an instance of {@link LambdaClient} to interact with the AWS Lambda service
     * @param functionName the name of the AWS Lambda function to be invoked
     */
    public static void invokeFunction(LambdaClient awsLambda, String functionName) {
        InvokeResponse res;
        try {
            // Need a SdkBytes instance for the payload.
            JSONObject jsonObj = new JSONObject();
            jsonObj.put("inputValue", "2000");
            String json = jsonObj.toString();
            SdkBytes payload = SdkBytes.fromUtf8String(json);

            InvokeRequest request = InvokeRequest.builder()
                .functionName(functionName)
                .payload(payload)
                .build();

            res = awsLambda.invoke(request);
            String value = res.payload().asUtf8String();
            System.out.println(value);

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

    /**
     * Updates the code for an AWS Lambda function.
     *
     * @param awsLambda  the AWS Lambda client
     * @param functionName the name of the Lambda function to update
     * @param bucketName the name of the S3 bucket where the function code is located
     * @param key the key (file name) of the function code in the S3 bucket
     * @throws LambdaException if there is an error updating the function code
     */
    public static void updateFunctionCode(LambdaClient awsLambda, String functionName, String bucketName, String key) {
        try {
            LambdaWaiter waiter = awsLambda.waiter();
            UpdateFunctionCodeRequest functionCodeRequest = UpdateFunctionCodeRequest.builder()
                .functionName(functionName)
                .publish(true)
                .s3Bucket(bucketName)
                .s3Key(key)
                .build();

            UpdateFunctionCodeResponse response = awsLambda.updateFunctionCode(functionCodeRequest);
            GetFunctionConfigurationRequest getFunctionConfigRequest = GetFunctionConfigurationRequest.builder()
                .functionName(functionName)
                .build();

            WaiterResponse<GetFunctionConfigurationResponse> waiterResponse = waiter
                .waitUntilFunctionUpdated(getFunctionConfigRequest);
            waiterResponse.matched().response().ifPresent(System.out::println);
            System.out.println("The last modified value is " + response.lastModified());

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

    /**
     * Updates the configuration of an AWS Lambda function.
     *
     * @param awsLambda     the {@link LambdaClient} instance to use for the AWS Lambda operation
     * @param functionName  the name of the AWS Lambda function to update
     * @param handler       the new handler for the AWS Lambda function
     *
     * @throws LambdaException if there is an error while updating the function configuration
     */
    public static void updateFunctionConfiguration(LambdaClient awsLambda, String functionName, String handler) {
        try {
            UpdateFunctionConfigurationRequest configurationRequest = UpdateFunctionConfigurationRequest.builder()
                .functionName(functionName)
                .handler(handler)
                .runtime(Runtime.JAVA17)
                .build();

            awsLambda.updateFunctionConfiguration(configurationRequest);

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

    /**
     * Deletes an AWS Lambda function.
     *
     * @param awsLambda     an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service
     * @param functionName  the name of the Lambda function to be deleted
     *
     * @throws LambdaException if an error occurs while deleting the Lambda function
     */
    public static void deleteLambdaFunction(LambdaClient awsLambda, String functionName) {
        try {
            DeleteFunctionRequest request = DeleteFunctionRequest.builder()
                .functionName(functionName)
                .build();

            awsLambda.deleteFunction(request);
            System.out.println("The " + functionName + " function was deleted");

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
}
```
+ 如需 API 詳細資訊，請參閱《*AWS SDK for Java 2.x API 參考*》中的下列主題。
  + [CreateFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/CreateFunction)
  + [DeleteFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/DeleteFunction)
  + [GetFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/GetFunction)
  + [Invoke](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/Invoke)
  + [ListFunctions](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/ListFunctions)
  + [UpdateFunctionCode](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/UpdateFunctionCode)
  + [UpdateFunctionConfiguration](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/UpdateFunctionConfiguration)

## 動作
<a name="actions"></a>

### `CreateFunction`
<a name="lambda_CreateFunction_java_2_topic"></a>

以下程式碼範例顯示如何使用 `CreateFunction`。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Creates a new Lambda function in AWS using the AWS Lambda Java API.
     *
     * @param awsLambda    the AWS Lambda client used to interact with the AWS Lambda service
     * @param functionName the name of the Lambda function to create
     * @param key          the S3 key of the function code
     * @param bucketName   the name of the S3 bucket containing the function code
     * @param role         the IAM role to assign to the Lambda function
     * @param handler      the fully qualified class name of the function handler
     * @return the Amazon Resource Name (ARN) of the created Lambda function
     */
    public static String createLambdaFunction(LambdaClient awsLambda,
                                              String functionName,
                                              String key,
                                              String bucketName,
                                              String role,
                                              String handler) {

        try {
            LambdaWaiter waiter = awsLambda.waiter();
            FunctionCode code = FunctionCode.builder()
                .s3Key(key)
                .s3Bucket(bucketName)
                .build();

            CreateFunctionRequest functionRequest = CreateFunctionRequest.builder()
                .functionName(functionName)
                .description("Created by the Lambda Java API")
                .code(code)
                .handler(handler)
                .runtime(Runtime.JAVA17)
                .role(role)
                .build();

            // Create a Lambda function using a waiter
            CreateFunctionResponse functionResponse = awsLambda.createFunction(functionRequest);
            GetFunctionRequest getFunctionRequest = GetFunctionRequest.builder()
                .functionName(functionName)
                .build();
            WaiterResponse<GetFunctionResponse> waiterResponse = waiter.waitUntilFunctionExists(getFunctionRequest);
            waiterResponse.matched().response().ifPresent(System.out::println);
            return functionResponse.functionArn();

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
        return "";
    }
```
+  如需 API 詳細資訊，請參閱《*AWS SDK for Java 2.x API 參考*》中的「[CreateFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/CreateFunction)」。

### `DeleteFunction`
<a name="lambda_DeleteFunction_java_2_topic"></a>

以下程式碼範例顯示如何使用 `DeleteFunction`。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Deletes an AWS Lambda function.
     *
     * @param awsLambda     an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service
     * @param functionName  the name of the Lambda function to be deleted
     *
     * @throws LambdaException if an error occurs while deleting the Lambda function
     */
    public static void deleteLambdaFunction(LambdaClient awsLambda, String functionName) {
        try {
            DeleteFunctionRequest request = DeleteFunctionRequest.builder()
                .functionName(functionName)
                .build();

            awsLambda.deleteFunction(request);
            System.out.println("The " + functionName + " function was deleted");

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
```
+  如需 API 詳細資訊，請參閱*《AWS SDK for Java 2.x API 參考》*中的 [DeleteFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/DeleteFunction)。

### `GetFunction`
<a name="lambda_GetFunction_java_2_topic"></a>

以下程式碼範例顯示如何使用 `GetFunction`。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Retrieves information about an AWS Lambda function.
     *
     * @param awsLambda    an instance of the {@link LambdaClient} class, which is used to interact with the AWS Lambda service
     * @param functionName the name of the AWS Lambda function to retrieve information about
     */
    public static void getFunction(LambdaClient awsLambda, String functionName) {
        try {
            GetFunctionRequest functionRequest = GetFunctionRequest.builder()
                .functionName(functionName)
                .build();

            GetFunctionResponse response = awsLambda.getFunction(functionRequest);
            System.out.println("The runtime of this Lambda function is " + response.configuration().runtime());

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [GetFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/GetFunction)。

### `Invoke`
<a name="lambda_Invoke_java_2_topic"></a>

以下程式碼範例顯示如何使用 `Invoke`。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Invokes a specific AWS Lambda function.
     *
     * @param awsLambda    an instance of {@link LambdaClient} to interact with the AWS Lambda service
     * @param functionName the name of the AWS Lambda function to be invoked
     */
    public static void invokeFunction(LambdaClient awsLambda, String functionName) {
        InvokeResponse res;
        try {
            // Need a SdkBytes instance for the payload.
            JSONObject jsonObj = new JSONObject();
            jsonObj.put("inputValue", "2000");
            String json = jsonObj.toString();
            SdkBytes payload = SdkBytes.fromUtf8String(json);

            InvokeRequest request = InvokeRequest.builder()
                .functionName(functionName)
                .payload(payload)
                .build();

            res = awsLambda.invoke(request);
            String value = res.payload().asUtf8String();
            System.out.println(value);

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [Invoke](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/Invoke)。

### `UpdateFunctionCode`
<a name="lambda_UpdateFunctionCode_java_2_topic"></a>

以下程式碼範例顯示如何使用 `UpdateFunctionCode`。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Updates the code for an AWS Lambda function.
     *
     * @param awsLambda  the AWS Lambda client
     * @param functionName the name of the Lambda function to update
     * @param bucketName the name of the S3 bucket where the function code is located
     * @param key the key (file name) of the function code in the S3 bucket
     * @throws LambdaException if there is an error updating the function code
     */
    public static void updateFunctionCode(LambdaClient awsLambda, String functionName, String bucketName, String key) {
        try {
            LambdaWaiter waiter = awsLambda.waiter();
            UpdateFunctionCodeRequest functionCodeRequest = UpdateFunctionCodeRequest.builder()
                .functionName(functionName)
                .publish(true)
                .s3Bucket(bucketName)
                .s3Key(key)
                .build();

            UpdateFunctionCodeResponse response = awsLambda.updateFunctionCode(functionCodeRequest);
            GetFunctionConfigurationRequest getFunctionConfigRequest = GetFunctionConfigurationRequest.builder()
                .functionName(functionName)
                .build();

            WaiterResponse<GetFunctionConfigurationResponse> waiterResponse = waiter
                .waitUntilFunctionUpdated(getFunctionConfigRequest);
            waiterResponse.matched().response().ifPresent(System.out::println);
            System.out.println("The last modified value is " + response.lastModified());

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [UpdateFunctionCode](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/UpdateFunctionCode)。

### `UpdateFunctionConfiguration`
<a name="lambda_UpdateFunctionConfiguration_java_2_topic"></a>

以下程式碼範例顯示如何使用 `UpdateFunctionConfiguration`。

**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/lambda#code-examples)中設定和執行。

```
    /**
     * Updates the configuration of an AWS Lambda function.
     *
     * @param awsLambda     the {@link LambdaClient} instance to use for the AWS Lambda operation
     * @param functionName  the name of the AWS Lambda function to update
     * @param handler       the new handler for the AWS Lambda function
     *
     * @throws LambdaException if there is an error while updating the function configuration
     */
    public static void updateFunctionConfiguration(LambdaClient awsLambda, String functionName, String handler) {
        try {
            UpdateFunctionConfigurationRequest configurationRequest = UpdateFunctionConfigurationRequest.builder()
                .functionName(functionName)
                .handler(handler)
                .runtime(Runtime.JAVA17)
                .build();

            awsLambda.updateFunctionConfiguration(configurationRequest);

        } catch (LambdaException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [UpdateFunctionConfiguration](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/UpdateFunctionConfiguration)。

## 案例
<a name="scenarios"></a>

### 建立無伺服器應用程式來管理相片
<a name="cross_PAM_java_2_topic"></a>

下列程式碼範例示範如何建立無伺服器應用程式，讓使用者以標籤管理相片。

**適用於 Java 2.x 的 SDK**  
 顯示如何開發照片資產管理應用程式，以便使用 Amazon Rekognition 偵測圖片中的標籤，並將其儲存以供日後擷取。  
如需完整的原始碼和如何設定及執行的指示，請參閱 [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/pam_source_files) 上的完整範例。  
如要深入探索此範例的來源，請參閱 [AWS  社群](https://community.aws/posts/cloud-journeys/01-serverless-image-recognition-app)上的文章。  

**此範例中使用的服務**
+ API Gateway
+ DynamoDB
+ Lambda
+ Amazon Rekognition
+ Amazon S3
+ Amazon SNS

### 建立應用程式以分析客戶意見回饋
<a name="cross_FSA_java_2_topic"></a>

下列程式碼範例會示範如何建立可分析客戶評論卡、從其原始語言進行翻譯、判斷對方情緒，以及透過翻譯後的文字產生音訊檔案的應用程式。

**適用於 Java 2.x 的 SDK**  
 此範例應用程式會分析和存儲客戶的意見回饋卡。具體來說，它滿足了紐約市一家虛構飯店的需求。飯店以實體評論卡的形式收到賓客以各種語言撰寫的意見回饋。這些意見回饋透過 Web 用戶端上傳至應用程式。評論卡的影像上傳後，系統會執行下列步驟：  
+ 文字內容是使用 Amazon Textract 從影像中擷取。
+ Amazon Comprehend 會決定擷取文字及其用語的情感。
+ 擷取的文字內容會使用 Amazon Translate 翻譯成英文。
+ Amazon Polly 會使用擷取的文字內容合成音訊檔案。
 完整的應用程式可透過  AWS CDK 部署。如需原始程式碼和部署的說明，請參閱 [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_fsa_app) 中的專案。  

**此範例中使用的服務**
+ Amazon Comprehend
+ Lambda
+ Amazon Polly
+ Amazon Textract
+ Amazon Translate

### 使用 API Gateway 來調用 Lambda 函式
<a name="cross_LambdaAPIGateway_java_2_topic"></a>

下列程式碼範例示範如何建立 Amazon API Gateway 調用的 AWS Lambda 函數。

**適用於 Java 2.x 的 SDK**  
 顯示如何使用 Lambda Java 執行時間 API 建立 AWS Lambda 函數。此範例會叫用不同的 AWS 服務來執行特定的使用案例。此範例示範如何建立 Amazon API Gateway 調用的 Lambda 函式，該函數會掃描 Amazon DynamoDB 資料表中的工作週年紀念日，並使用 Amazon Simple Notification Service (Amazon SNS) 傳送文字訊息給您的員工，在他們的週年紀念日向他們道賀。  
 如需完整的原始碼和如何設定及執行的指示，請參閱 [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_lambda_apigateway) 上的完整範例。  

**此範例中使用的服務**
+ API Gateway
+ DynamoDB
+ Lambda
+ Amazon SNS

### 使用 Step Functions 調用 Lambda 函式
<a name="cross_ServerlessWorkflows_java_2_topic"></a>

下列程式碼範例示範如何建立依序叫用 AWS Lambda 函數 AWS Step Functions 的狀態機器。

**適用於 Java 2.x 的 SDK**  
 顯示如何使用 AWS Step Functions 和 建立無 AWS 伺服器工作流程 AWS SDK for Java 2.x。每個工作流程步驟都是使用 AWS Lambda 函數實作。  
 如需完整的原始碼和如何設定及執行的指示，請參閱 [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_workflows_stepfunctions) 上的完整範例。  

**此範例中使用的服務**
+ DynamoDB
+ Lambda
+ Amazon SES
+ 步驟函數

### 使用排程事件來調用 Lambda 函式
<a name="cross_LambdaScheduledEvents_java_2_topic"></a>

下列程式碼範例示範如何建立由 Amazon EventBridge 排程事件呼叫的 AWS Lambda 函數。

**適用於 Java 2.x 的 SDK**  
 顯示如何建立叫用 AWS Lambda 函數的 Amazon EventBridge 排程事件。將 EventBridge 設定為在調用 Lambda 函式時使用 Cron 表達式來進行排程。在此範例中，您會使用 Lambda Java 執行時期 API 建立 Lambda 函式。此範例會叫用不同的 AWS 服務來執行特定的使用案例。此範例示範如何建立應用程式，將行動裝置文字訊息傳送給員工，在他們的週年紀念日向他們道賀。  
 如需完整的原始碼和如何設定及執行的指示，請參閱 [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_scheduled_events) 上的完整範例。  

**此範例中使用的服務**
+ CloudWatch Logs
+ DynamoDB
+ EventBridge
+ Lambda
+ Amazon SNS

### 使用 Neptune API 查詢圖形資料
<a name="cross_Neptune_Query_java_2_topic"></a>

下列程式碼範例示範如何使用 Neptune API 查詢圖形資料。

**適用於 Java 2.x 的 SDK**  
 示範如何使用 Amazon Neptune Java API 建立 Lambda 函式，查詢 VPC 中的圖形資料。  
 如需完整的原始碼和如何設定及執行的指示，請參閱 [GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_neptune_lambda) 上的完整範例。  

**此範例中使用的服務**
+ Lambda
+ Neptune

## 無伺服器範例
<a name="serverless_examples"></a>

### 連線至 Lambda 函數中的 Amazon RDS 資料庫
<a name="serverless_connect_RDS_Lambda_java_2_topic"></a>

以下程式碼範例示範如何實作連線至 RDS 資料庫的 Lambda 函式。該函數會提出簡單的資料庫請求並傳回結果。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/lambda-function-connect-rds-iam)儲存庫中設定和執行。
使用 Java 連線至 Lambda 函數中的 Amazon RDS 資料庫。  

```
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyRequestEvent;
import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent;
import software.amazon.awssdk.auth.credentials.DefaultCredentialsProvider;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.rdsdata.RdsDataClient;
import software.amazon.awssdk.services.rdsdata.model.ExecuteStatementRequest;
import software.amazon.awssdk.services.rdsdata.model.ExecuteStatementResponse;
import software.amazon.awssdk.services.rdsdata.model.Field;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

public class RdsLambdaHandler implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {

    @Override
    public APIGatewayProxyResponseEvent handleRequest(APIGatewayProxyRequestEvent event, Context context) {
        APIGatewayProxyResponseEvent response = new APIGatewayProxyResponseEvent();

        try {
            // Obtain auth token
            String token = createAuthToken();

            // Define connection configuration
            String connectionString = String.format("jdbc:mysql://%s:%s/%s?useSSL=true&requireSSL=true",
                    System.getenv("ProxyHostName"),
                    System.getenv("Port"),
                    System.getenv("DBName"));

            // Establish a connection to the database
            try (Connection connection = DriverManager.getConnection(connectionString, System.getenv("DBUserName"), token);
                 PreparedStatement statement = connection.prepareStatement("SELECT ? + ? AS sum")) {

                statement.setInt(1, 3);
                statement.setInt(2, 2);

                try (ResultSet resultSet = statement.executeQuery()) {
                    if (resultSet.next()) {
                        int sum = resultSet.getInt("sum");
                        response.setStatusCode(200);
                        response.setBody("The selected sum is: " + sum);
                    }
                }
            }

        } catch (Exception e) {
            response.setStatusCode(500);
            response.setBody("Error: " + e.getMessage());
        }

        return response;
    }

    private String createAuthToken() {
        // Create RDS Data Service client
        RdsDataClient rdsDataClient = RdsDataClient.builder()
                .region(Region.of(System.getenv("AWS_REGION")))
                .credentialsProvider(DefaultCredentialsProvider.create())
                .build();

        // Define authentication request
        ExecuteStatementRequest request = ExecuteStatementRequest.builder()
                .resourceArn(System.getenv("ProxyHostName"))
                .secretArn(System.getenv("DBUserName"))
                .database(System.getenv("DBName"))
                .sql("SELECT 'RDS IAM Authentication'")
                .build();

        // Execute request and obtain authentication token
        ExecuteStatementResponse response = rdsDataClient.executeStatement(request);
        Field tokenField = response.records().get(0).get(0);

        return tokenField.stringValue();
    }
}
```

### 使用 Kinesis 觸發條件調用 Lambda 函數
<a name="serverless_Kinesis_Lambda_java_2_topic"></a>

以下程式碼範例示範如何實作 Lambda 函式，該函式會透過接收 Kinesis 串流的記錄來接收所觸發的事件。此函數會擷取 Kinesis 承載、從 Base64 解碼，並記錄記錄內容。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-kinesis-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 來使用 Kinesis 事件。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
package example;

import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.LambdaLogger;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.KinesisEvent;

public class Handler implements RequestHandler<KinesisEvent, Void> {
    @Override
    public Void handleRequest(final KinesisEvent event, final Context context) {
        LambdaLogger logger = context.getLogger();
        if (event.getRecords().isEmpty()) {
            logger.log("Empty Kinesis Event received");
            return null;
        }
        for (KinesisEvent.KinesisEventRecord record : event.getRecords()) {
            try {
                logger.log("Processed Event with EventId: "+record.getEventID());
                String data = new String(record.getKinesis().getData().array());
                logger.log("Data:"+ data);
                // TODO: Do interesting work based on the new data
            }
            catch (Exception ex) {
                logger.log("An error occurred:"+ex.getMessage());
                throw ex;
            }
        }
        logger.log("Successfully processed:"+event.getRecords().size()+" records");
        return null;
    }

}
```

### 使用 DynamoDB 觸發條件調用 Lambda 函式
<a name="serverless_DynamoDB_Lambda_java_2_topic"></a>

以下程式碼範例示範如何實作 Lambda 函式，該函式會透過接收 DynamoDB 串流的記錄來接收所觸發的事件。函數會擷取 DynamoDB 承載並記下記錄內容。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-ddb-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 來使用 DynamoDB 事件。  

```
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.DynamodbEvent;
import com.amazonaws.services.lambda.runtime.events.DynamodbEvent.DynamodbStreamRecord;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

public class example implements RequestHandler<DynamodbEvent, Void> {

    private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();

    @Override
    public Void handleRequest(DynamodbEvent event, Context context) {
        System.out.println(GSON.toJson(event));
        event.getRecords().forEach(this::logDynamoDBRecord);
        return null;
    }

    private void logDynamoDBRecord(DynamodbStreamRecord record) {
        System.out.println(record.getEventID());
        System.out.println(record.getEventName());
        System.out.println("DynamoDB Record: " + GSON.toJson(record.getDynamodb()));
    }
}
```

### 使用 Amazon DocumentDB 觸發條件調用 Lambda 函數
<a name="serverless_DocumentDB_Lambda_java_2_topic"></a>

以下程式碼範例示範如何實作 Lambda 函式，該函式會透過接收 DocumentDB 變更串流的記錄來接收所觸發的事件。函數會擷取 DocumentDB 承載並記下記錄內容。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-docdb-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 使用 Amazon DocumentDB 事件。  

```
import java.util.List;
import java.util.Map;

import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;

public class Example implements RequestHandler<Map<String, Object>, String> {

    @SuppressWarnings("unchecked")
    @Override
    public String handleRequest(Map<String, Object> event, Context context) {
        List<Map<String, Object>> events = (List<Map<String, Object>>) event.get("events");
        for (Map<String, Object> record : events) {
            Map<String, Object> eventData = (Map<String, Object>) record.get("event");
            processEventData(eventData);
        }

        return "OK";
    }

    @SuppressWarnings("unchecked")
    private void processEventData(Map<String, Object> eventData) {
        String operationType = (String) eventData.get("operationType");
        System.out.println("operationType: %s".formatted(operationType));

        Map<String, Object> ns = (Map<String, Object>) eventData.get("ns");

        String db = (String) ns.get("db");
        System.out.println("db: %s".formatted(db));
        String coll = (String) ns.get("coll");
        System.out.println("coll: %s".formatted(coll));

        Map<String, Object> fullDocument = (Map<String, Object>) eventData.get("fullDocument");
        System.out.println("fullDocument: %s".formatted(fullDocument));
    }

}
```

### 使用 Amazon MSK 觸發條件調用 Lambda 函數
<a name="serverless_MSK_Lambda_java_2_topic"></a>

以下程式碼範例示範如何實作 Lambda 函式，該函式會透過接收 Amazon MSK 叢集的記錄來接收所觸發的事件。函數會擷取 MSK 承載並記下記錄內容。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-msk-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 來取用 Amazon MSK 事件。  

```
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.KafkaEvent;
import com.amazonaws.services.lambda.runtime.events.KafkaEvent.KafkaEventRecord;

import java.util.Base64;
import java.util.Map;

public class Example implements RequestHandler<KafkaEvent, Void> {

    @Override
    public Void handleRequest(KafkaEvent event, Context context) {
        for (Map.Entry<String, java.util.List<KafkaEventRecord>> entry : event.getRecords().entrySet()) {
            String key = entry.getKey();
            System.out.println("Key: " + key);

            for (KafkaEventRecord record : entry.getValue()) {
                System.out.println("Record: " + record);

                byte[] value = Base64.getDecoder().decode(record.getValue());
                String message = new String(value);
                System.out.println("Message: " + message);
            }
        }

        return null;
    }
}
```

### 使用 Amazon S3 觸發條件調用 Lambda 函數
<a name="serverless_S3_Lambda_java_2_topic"></a>

下列程式碼範例示範如何實作 Lambda 函式，該函式接收透過上傳物件至 S3 儲存貯體時所觸發的事件。此函數會從事件參數擷取 S3 儲存貯體名稱和物件金鑰，並呼叫 Amazon S3 API 以擷取和記錄物件的內容類型。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-s3-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 來使用 S3 事件。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
package example;

import software.amazon.awssdk.services.s3.model.HeadObjectRequest;
import software.amazon.awssdk.services.s3.model.HeadObjectResponse;
import software.amazon.awssdk.services.s3.S3Client;

import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.S3Event;
import com.amazonaws.services.lambda.runtime.events.models.s3.S3EventNotification.S3EventNotificationRecord;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Handler implements RequestHandler<S3Event, String> {
    private static final Logger logger = LoggerFactory.getLogger(Handler.class);
    @Override
    public String handleRequest(S3Event s3event, Context context) {
        try {
          S3EventNotificationRecord record = s3event.getRecords().get(0);
          String srcBucket = record.getS3().getBucket().getName();
          String srcKey = record.getS3().getObject().getUrlDecodedKey();

          S3Client s3Client = S3Client.builder().build();
          HeadObjectResponse headObject = getHeadObject(s3Client, srcBucket, srcKey);

          logger.info("Successfully retrieved " + srcBucket + "/" + srcKey + " of type " + headObject.contentType());

          return "Ok";
        } catch (Exception e) {
          throw new RuntimeException(e);
        }
    }

    private HeadObjectResponse getHeadObject(S3Client s3Client, String bucket, String key) {
        HeadObjectRequest headObjectRequest = HeadObjectRequest.builder()
                .bucket(bucket)
                .key(key)
                .build();
        return s3Client.headObject(headObjectRequest);
    }
}
```

### 使用 Amazon SNS 觸發條件調用 Lambda 函數
<a name="serverless_SNS_Lambda_java_2_topic"></a>

下列程式碼範例示範如何實作 Lambda 函式，該函式會透過接收 SNS 主題的訊息來接收所觸發的事件。函數會從事件參數擷取訊息，並記錄每一則訊息的內容。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-sns-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 來使用 SNS 事件。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
package example;

import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.LambdaLogger;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.SNSEvent;
import com.amazonaws.services.lambda.runtime.events.SNSEvent.SNSRecord;


import java.util.Iterator;
import java.util.List;

public class SNSEventHandler implements RequestHandler<SNSEvent, Boolean> {
    LambdaLogger logger;

    @Override
    public Boolean handleRequest(SNSEvent event, Context context) {
        logger = context.getLogger();
        List<SNSRecord> records = event.getRecords();
        if (!records.isEmpty()) {
            Iterator<SNSRecord> recordsIter = records.iterator();
            while (recordsIter.hasNext()) {
                processRecord(recordsIter.next());
            }
        }
        return Boolean.TRUE;
    }

    public void processRecord(SNSRecord record) {
        try {
            String message = record.getSNS().getMessage();
            logger.log("message: " + message);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

}
```

### 使用 Amazon SQS 觸發條件調用 Lambda 函數
<a name="serverless_SQS_Lambda_java_2_topic"></a>

下列程式碼範例示範如何實作 Lambda 函式，該函式會透過接收 SQS 佇列的訊息來接收所觸發的事件。函數會從事件參數擷取訊息，並記錄每一則訊息的內容。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-sqs-to-lambda)儲存庫中設定和執行。
使用 Java 搭配 Lambda 來使用 SQS 事件。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.SQSEvent;
import com.amazonaws.services.lambda.runtime.events.SQSEvent.SQSMessage;

public class Function implements RequestHandler<SQSEvent, Void> {
    @Override
    public Void handleRequest(SQSEvent sqsEvent, Context context) {
        for (SQSMessage msg : sqsEvent.getRecords()) {
            processMessage(msg, context);
        }
        context.getLogger().log("done");
        return null;
    }

    private void processMessage(SQSMessage msg, Context context) {
        try {
            context.getLogger().log("Processed message " + msg.getBody());

            // TODO: Do interesting work based on the new message

        } catch (Exception e) {
            context.getLogger().log("An error occurred");
            throw e;
        }

    }
}
```

### 使用 Kinesis 觸發條件報告 Lambda 函數的批次項目失敗
<a name="serverless_Kinesis_Lambda_batch_item_failures_java_2_topic"></a>

下列程式碼範例示範如何針對接收來自 Kinesis 串流之事件的 Lambda 函式，實作部分批次回應。此函數會在回應中報告批次項目失敗，指示 Lambda 稍後重試這些訊息。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-kinesis-to-lambda-with-batch-item-handling)儲存庫中設定和執行。
透過使用 Java 的 Lambda 報告 Kinesis 批次項目失敗。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.KinesisEvent;
import com.amazonaws.services.lambda.runtime.events.StreamsEventResponse;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;

public class ProcessKinesisRecords implements RequestHandler<KinesisEvent, StreamsEventResponse> {

    @Override
    public StreamsEventResponse handleRequest(KinesisEvent input, Context context) {

        List<StreamsEventResponse.BatchItemFailure> batchItemFailures = new ArrayList<>();
        String curRecordSequenceNumber = "";

        for (KinesisEvent.KinesisEventRecord kinesisEventRecord : input.getRecords()) {
            try {
                //Process your record
                KinesisEvent.Record kinesisRecord = kinesisEventRecord.getKinesis();
                curRecordSequenceNumber = kinesisRecord.getSequenceNumber();

            } catch (Exception e) {
                /* Since we are working with streams, we can return the failed item immediately.
                   Lambda will immediately begin to retry processing from this failed item onwards. */
                batchItemFailures.add(new StreamsEventResponse.BatchItemFailure(curRecordSequenceNumber));
                return new StreamsEventResponse(batchItemFailures);
            }
        }
       
       return new StreamsEventResponse(batchItemFailures);   
    }
}
```

### 使用 DynamoDB 觸發條件報告 Lambda 函式的批次項目失敗
<a name="serverless_DynamoDB_Lambda_batch_item_failures_java_2_topic"></a>

下列程式碼範例示範如何針對接收來自 DynamoDB 串流之事件的 Lambda 函式，實作部分批次回應。此函數會在回應中報告批次項目失敗，指示 Lambda 稍後重試這些訊息。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-ddb-to-lambda-with-batch-item-handling)儲存庫中設定和執行。
使用 Java 搭配 Lambda 報告 DynamoDB 批次項目失敗。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.DynamodbEvent;
import com.amazonaws.services.lambda.runtime.events.StreamsEventResponse;
import com.amazonaws.services.lambda.runtime.events.models.dynamodb.StreamRecord;

import java.util.ArrayList;
import java.util.List;

public class ProcessDynamodbRecords implements RequestHandler<DynamodbEvent, StreamsEventResponse> {

    @Override
    public StreamsEventResponse handleRequest(DynamodbEvent input, Context context) {

        List<StreamsEventResponse.BatchItemFailure> batchItemFailures = new ArrayList<>();
        String curRecordSequenceNumber = "";

        for (DynamodbEvent.DynamodbStreamRecord dynamodbStreamRecord : input.getRecords()) {
          try {
                //Process your record
                StreamRecord dynamodbRecord = dynamodbStreamRecord.getDynamodb();
                curRecordSequenceNumber = dynamodbRecord.getSequenceNumber();
                
            } catch (Exception e) {
                /* Since we are working with streams, we can return the failed item immediately.
                   Lambda will immediately begin to retry processing from this failed item onwards. */
                batchItemFailures.add(new StreamsEventResponse.BatchItemFailure(curRecordSequenceNumber));
                return new StreamsEventResponse(batchItemFailures);
            }
        }
       
       return new StreamsEventResponse();   
    }
}
```

### 使用 Amazon SQS 觸發條件報告 Lambda 函數的批次項目失敗
<a name="serverless_SQS_Lambda_batch_item_failures_java_2_topic"></a>

下列程式碼範例示範如何為接收從 SQS 佇列接收事件的 Lambda 函式，實作部分批次回應。此函數會在回應中報告批次項目失敗，指示 Lambda 稍後重試這些訊息。

**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[無伺服器範例](https://github.com/aws-samples/serverless-snippets/tree/main/lambda-function-sqs-report-batch-item-failures)儲存庫中設定和執行。
使用 Java 搭配 Lambda 報告 SQS 批次項目失敗。  

```
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.events.SQSEvent;
import com.amazonaws.services.lambda.runtime.events.SQSBatchResponse;
 
import java.util.ArrayList;
import java.util.List;
 
public class ProcessSQSMessageBatch implements RequestHandler<SQSEvent, SQSBatchResponse> {
    @Override
    public SQSBatchResponse handleRequest(SQSEvent sqsEvent, Context context) {
         List<SQSBatchResponse.BatchItemFailure> batchItemFailures = new ArrayList<SQSBatchResponse.BatchItemFailure>();

         for (SQSEvent.SQSMessage message : sqsEvent.getRecords()) {
             try {
                 //process your message
             } catch (Exception e) {
                 //Add failed message identifier to the batchItemFailures list
                 batchItemFailures.add(new SQSBatchResponse.BatchItemFailure(message.getMessageId()));
             }
         }
         return new SQSBatchResponse(batchItemFailures);
     }
}
```

## AWS 社群貢獻
<a name="aws_community_contributions"></a>

### 建置和測試無伺服器應用程式
<a name="tributary-lite_serverless-application_java_2_topic"></a>

下列程式碼範例示範如何搭配 Lambda 和 DynamoDB 使用 API Gateway，建置和測試無伺服器應用程式

**適用於 Java 2.x 的 SDK**  
 示範如何使用 Java SDK 建置和測試無伺服器應用程式，而該應用程式是由具有 Lambda 和 DynamoDB 的 API Gateway 組成。  
 如需完整的原始碼和如何設定及執行的指示，請參閱 [GitHub](https://github.com/aws-samples/serverless-java-frameworks-samples) 上的完整範例。  

**此範例中使用的服務**
+ API Gateway
+ DynamoDB
+ Lambda