

文档 AWS SDK 示例 GitHub 存储库中还有更多 [S AWS DK 示例](https://github.com/awsdocs/aws-doc-sdk-examples)。

本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

# 使用 SDK for Java 2.x 的 SDK 的 Lambda 示例
<a name="java_2_lambda_code_examples"></a>

以下代码示例向您展示了如何使用 with Lambda 来执行操作和实现常见场景。 AWS SDK for Java 2.x 

*基本功能*是向您展示如何在服务中执行基本操作的代码示例。

*操作*是大型程序的代码摘录，必须在上下文中运行。您可以通过操作了解如何调用单个服务函数，还可以通过函数相关场景的上下文查看操作。

*场景*是向您展示如何通过在一个服务中调用多个函数或与其他 AWS 服务服务结合来完成特定任务的代码示例。

*AWS 社区贡献*就是由多个团队创建和维护的示例 AWS。要提供反馈，请使用链接存储库中提供的机制。

每个示例都包含一个指向完整源代码的链接，您可以从中找到有关如何在上下文中设置和运行代码的说明。

**Topics**
+ [开始使用](#get_started)
+ [基本功能](#basics)
+ [操作](#actions)
+ [场景](#scenarios)
+ [无服务器示例](#serverless_examples)
+ [AWS 社区捐款](#aws_community_contributions)

## 开始使用
<a name="get_started"></a>

### 开始使用 Lambda
<a name="lambda_Hello_java_2_topic"></a>

以下代码示例展示了如何开始使用 Lambda。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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);
        }
    }
```
+  有关 API 的详细信息，请参阅 *AWS SDK for Java 2.x API 参考[ListFunctions](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/ListFunctions)*中的。

## 基本功能
<a name="basics"></a>

### 了解基本功能
<a name="lambda_Scenario_GettingStartedFunctions_java_2_topic"></a>

以下代码示例展示了如何：
+ 创建 IAM 角色和 Lambda 函数，然后上传处理程序代码。
+ 使用单个参数来调用函数并获取结果。
+ 更新函数代码并使用环境变量进行配置。
+ 使用新参数来调用函数并获取结果。显示返回的执行日志。
+ 列出账户函数，然后清除函数。

有关更多信息，请参阅[使用控制台创建 Lambda 函数](https://docs.aws.amazon.com/lambda/latest/dg/getting-started-create-function.html)。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples) 中查找完整示例，了解如何进行设置和运行。

```
/*
 *  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);
        }
    }
}
```
+ 有关 API 详细信息，请参阅《AWS SDK for Java 2.x API Reference》**中的以下主题。
  + [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)

## 操作
<a name="actions"></a>

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

以下代码示例演示了如何使用 `CreateFunction`。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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 "";
    }
```
+  有关 API 的详细信息，请参阅 *AWS SDK for Java 2.x API 参考[CreateFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/CreateFunction)*中的。

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

以下代码示例演示了如何使用 `DeleteFunction`。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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);
        }
    }
```
+  有关 API 的详细信息，请参阅 *AWS SDK for Java 2.x API 参考[DeleteFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/DeleteFunction)*中的。

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

以下代码示例演示了如何使用 `GetFunction`。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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);
        }
    }
```
+  有关 API 的详细信息，请参阅 *AWS SDK for Java 2.x API 参考[GetFunction](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/GetFunction)*中的。

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

以下代码示例演示了如何使用 `Invoke`。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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);
        }
    }
```
+  有关 API 详细信息，请参阅《AWS SDK for Java 2.x API Reference》**中的 [Invoke](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/Invoke)。

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

以下代码示例演示了如何使用 `UpdateFunctionCode`。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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);
        }
    }
```
+  有关 API 的详细信息，请参阅 *AWS SDK for Java 2.x API 参考[UpdateFunctionCode](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/UpdateFunctionCode)*中的。

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

以下代码示例演示了如何使用 `UpdateFunctionConfiguration`。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在 [AWS 代码示例存储库](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/lambda#code-examples)中查找完整示例，了解如何进行设置和运行。

```
    /**
     * 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);
        }
    }
```
+  有关 API 的详细信息，请参阅 *AWS SDK for Java 2.x API 参考[UpdateFunctionConfiguration](https://docs.aws.amazon.com/goto/SdkForJavaV2/lambda-2015-03-31/UpdateFunctionConfiguration)*中的。

## 场景
<a name="scenarios"></a>

### 创建无服务器应用程序来管理照片
<a name="cross_PAM_java_2_topic"></a>

以下代码示例演示如何创建无服务器应用程序，让用户能够使用标签管理照片。

**适用于 Java 的 SDK 2.x**  
 演示如何开发照片资产管理应用程序，该应用程序使用 Amazon Rekognition 检测图像中的标签并将其存储以供日后检索。  
有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[ GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/pam_source_files)。  
要深入了解这个例子的起源，请参阅 [AWS 社区](https://community.aws/posts/cloud-journeys/01-serverless-image-recognition-app)上的博文。  

**本示例中使用的服务**
+ API Gateway
+ DynamoDB
+ Lambda
+ Amazon Rekognition
+ Amazon S3
+ Amazon SNS

### 创建用于分析客户反馈的应用程序
<a name="cross_FSA_java_2_topic"></a>

以下代码示例说明如何创建应用程序来分析客户意见卡、翻译其母语、确定其情绪并根据译后的文本生成音频文件。

**适用于 Java 的 SDK 2.x**  
 此示例应用程序可分析并存储客户反馈卡。具体来说，它满足了纽约市一家虚构酒店的需求。酒店以实体意见卡的形式收集来自不同语种的客人的反馈。该反馈通过 Web 客户端上传到应用程序中。意见卡图片上传后，将执行以下步骤：  
+ 使用 Amazon Textract 从图片中提取文本。
+ Amazon Comprehend 确定所提取文本的情绪及其语言。
+ 使用 Amazon Translate 将所提取文本翻译为英语。
+ Amazon Polly 根据所提取文本合成音频文件。
 完整的应用程序可使用  AWS CDK 进行部署。有关源代码和部署说明，请参阅中的项目[ GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_fsa_app)。  

**本示例中使用的服务**
+ Amazon Comprehend
+ Lambda
+ Amazon Polly
+ Amazon Textract
+ Amazon Translate

### 使用 API Gateway 调用 Lambda 函数
<a name="cross_LambdaAPIGateway_java_2_topic"></a>

以下代码示例展示了如何创建由 Amazon API Gateway 调用的 AWS Lambda 函数。

**适用于 Java 的 SDK 2.x**  
 演示如何使用 Lambda Java 运行时 API 创建 AWS Lambda 函数。此示例调用不同的 AWS 服务来执行特定的用例。此示例展示了如何创建通过 Amazon API Gateway 调用的 Lambda 函数，该函数扫描 Amazon DynamoDB 表获取工作周年纪念日，并使用 Amazon Simple Notiﬁcation Service (Amazon SNS)向员工发送文本消息，祝贺他们的周年纪念日。  
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_lambda_apigateway)。  

**本示例中使用的服务**
+ API Gateway
+ DynamoDB
+ Lambda
+ Amazon SNS

### 使用 Step Functions 调用 Lambda 函数
<a name="cross_ServerlessWorkflows_java_2_topic"></a>

以下代码示例显示如何创建按顺序调用 AWS Lambda 函数的 AWS Step Functions 状态机。

**适用于 Java 的 SDK 2.x**  
 演示如何使用 AWS Step Functions 和创建 AWS 无服务器工作流程。 AWS SDK for Java 2.x每个工作流程步骤都是使用 AWS Lambda 函数实现的。  
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_workflows_stepfunctions)。  

**本示例中使用的服务**
+ DynamoDB
+ Lambda
+ Amazon SES
+ Step Functions

### 使用计划的事件调用 Lambda 函数
<a name="cross_LambdaScheduledEvents_java_2_topic"></a>

以下代码示例显示如何创建由 Amazon EventBridge 计划事件调用的 AWS Lambda 函数。

**适用于 Java 的 SDK 2.x**  
 演示如何创建调用函数的 Amazon EventBridge 计划事件。 AWS Lambda 配置 EventBridge 为使用 cron 表达式来调度 Lambda 函数的调用时间。在本示例中，您使用 Lambda Java 运行时 API 创建 Lambda 函数。此示例调用不同的 AWS 服务来执行特定的用例。此示例展示了如何创建一个应用程序，在其一周年纪念日时向员工发送移动短信表示祝贺。  
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_scheduled_events)。  

**本示例中使用的服务**
+ CloudWatch 日志
+ DynamoDB
+ EventBridge
+ Lambda
+ Amazon SNS

### 使用 Neptune API 查询图形数据
<a name="cross_Neptune_Query_java_2_topic"></a>

以下代码示例展示了如何使用 Neptune API 查询图形数据。

**适用于 Java 的 SDK 2.x**  
 展示如何使用 Amazon Neptune Java API 创建查询 VPC 内的图形数据的 Lambda 函数。  
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/creating_neptune_lambda)。  

**本示例中使用的服务**
+ Lambda
+ Neptune

## 无服务器示例
<a name="serverless_examples"></a>

### 使用 Lambda 函数连接到 Amazon RDS 数据库
<a name="serverless_connect_RDS_Lambda_java_2_topic"></a>

以下代码示例显示如何实现连接到 RDS 数据库的 Lambda 函数。该函数发出一个简单的数据库请求并返回结果。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/lambda-function-connect-rds-iam)存储库中查找完整示例，并了解如何进行设置和运行。
在 Lambda 函数中使用 Java 连接到 Amazon RDS 数据库。  

```
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();
    }
}
```

### 通过 Kinesis 触发器调用 Lambda 函数
<a name="serverless_Kinesis_Lambda_java_2_topic"></a>

以下代码示例展示了如何实现一个 Lambda 函数，该函数接收因接收来自 Kinesis 流的记录而触发的事件。该函数检索 Kinesis 有效负载，将 Base64 解码，并记录下记录内容。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-kinesis-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
使用 Java 将 Kinesis 事件与 Lambda 结合使用。  

```
// 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;
    }

}
```

### 通过 DynamoDB 触发器调用 Lambda 函数
<a name="serverless_DynamoDB_Lambda_java_2_topic"></a>

以下代码示例演示如何实现一个 Lambda 函数，该函数接收通过接收来自 DynamoDB 流的记录而触发的事件。该函数检索 DynamoDB 有效负载，并记录下记录内容。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-ddb-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
使用 Java 将 DynamoDB 事件与 Lambda 结合使用。  

```
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()));
    }
}
```

### 通过 Amazon DocumentDB 触发器调用 Lambda 函数
<a name="serverless_DocumentDB_Lambda_java_2_topic"></a>

以下代码示例演示如何实现一个 Lambda 函数，该函数接收通过接收来自 DocumentDB 更改流的记录而触发的事件。该函数检索 DocumentDB 有效负载，并记录下记录内容。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-docdb-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
使用 Java 将 Amazon DocumentDB 事件与 Lambda 结合使用。  

```
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));
    }

}
```

### 通过 Amazon MSK 触发器调用 Lambda 函数
<a name="serverless_MSK_Lambda_java_2_topic"></a>

以下代码示例演示如何实现一个 Lambda 函数，该函数接收通过接收来自 Amazon MSK 集群的记录而触发的事件。该函数检索 MSK 有效负载，并记录下记录内容。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-msk-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
通过 Java 将 Amazon MSK 事件与 Lambda 结合使用。  

```
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;
    }
}
```

### 通过 Amazon S3 触发器调用 Lambda 函数
<a name="serverless_S3_Lambda_java_2_topic"></a>

以下代码示例展示了如何实现一个 Lambda 函数，该函数接收通过将对象上传到 S3 桶而触发的事件。该函数从事件参数中检索 S3 存储桶名称和对象密钥，并调用 Amazon S3 API 来检索和记录对象的内容类型。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-s3-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
使用 Java 将 S3 事件与 Lambda 结合使用。  

```
// 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);
    }
}
```

### 通过 Amazon SNS 触发器调用 Lambda 函数
<a name="serverless_SNS_Lambda_java_2_topic"></a>

以下代码示例展示了如何实现一个 Lambda 函数，该函数接收因接收来自 SNS 主题的消息而触发的事件。该函数从事件参数检索消息并记录每条消息的内容。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-sns-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
通过 Java 将 SNS 事件与 Lambda 结合使用。  

```
// 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);
        }
    }

}
```

### 通过 Amazon SQS 触发器调用 Lambda 函数
<a name="serverless_SQS_Lambda_java_2_topic"></a>

以下代码示例展示了如何实现一个 Lambda 函数，该函数接收因接收来自 SNS 队列的消息而触发的事件。该函数从事件参数检索消息并记录每条消息的内容。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-sqs-to-lambda)存储库中查找完整示例，并了解如何进行设置和运行。
通过 Java 将 SQS 事件与 Lambda 结合使用。  

```
// 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;
        }

    }
}
```

### 通过 Kinesis 触发器报告 Lambda 函数批处理项目失败
<a name="serverless_Kinesis_Lambda_batch_item_failures_java_2_topic"></a>

以下代码示例展示了如何为接收来自 Kinesis 流的事件的 Lambda 函数实现部分批处理响应。该函数在响应中报告批处理项目失败，并指示 Lambda 稍后重试这些消息。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-kinesis-to-lambda-with-batch-item-handling)存储库中查找完整示例，并了解如何进行设置和运行。
报告使用 Java 进行 Lambda Kinesis 批处理项目失败。  

```
// 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);   
    }
}
```

### 通过 DynamoDB 触发器报告 Lambda 函数批处理项目失败
<a name="serverless_DynamoDB_Lambda_batch_item_failures_java_2_topic"></a>

以下代码示例演示如何为接收来自 DynamoDB 流的事件的 Lambda 函数实现部分批处理响应。该函数在响应中报告批处理项目失败，并指示 Lambda 稍后重试这些消息。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/integration-ddb-to-lambda-with-batch-item-handling)存储库中查找完整示例，并了解如何进行设置和运行。
报告使用 Java 通过 Lambda 进行 DynamoDB 批处理项目失败。  

```
// 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();   
    }
}
```

### 报告使用 Amazon SQS 触发器进行 Lambda 函数批处理项目失败
<a name="serverless_SQS_Lambda_batch_item_failures_java_2_topic"></a>

以下代码示例展示了如何为接收来自 SQS 队列的事件的 Lambda 函数实现部分批处理响应。该函数在响应中报告批处理项目失败，并指示 Lambda 稍后重试这些消息。

**适用于 Java 的 SDK 2.x**  
 还有更多相关信息 GitHub。在[无服务器示例](https://github.com/aws-samples/serverless-snippets/tree/main/lambda-function-sqs-report-batch-item-failures)存储库中查找完整示例，并了解如何进行设置和运行。
报告使用 Java 进行 Lambda SQS 批处理项目失败。  

```
// 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 社区捐款
<a name="aws_community_contributions"></a>

### 构建和测试无服务器应用程序
<a name="tributary-lite_serverless-application_java_2_topic"></a>

以下代码示例演示如何使用 API Gateway 与 Lambda 和 DynamoDB 构建和测试无服务器应用程序

**适用于 Java 的 SDK 2.x**  
 演示如何使用 Java SDK 构建和测试包含 API Gateway 以及 Lambda 和 DynamoDB 的无服务器应用程序。  
 有关如何设置和运行的完整源代码和说明，请参阅上的完整示例[GitHub](https://github.com/aws-samples/serverless-java-frameworks-samples)。  

**本示例中使用的服务**
+ API Gateway
+ DynamoDB
+ Lambda