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使用適用於 Java 2.x 的 SDK 的 Lambda 範例 - AWS SDK for Java 2.x

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

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。

開始使用

下列程式碼範例示範如何開始使用 Lambda。

SDK for Java 2.x
注意

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

基本概念

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

SDK for Java 2.x
注意

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); } } }

動作

以下程式碼範例顯示如何使用 CreateFunction

SDK for Java 2.x
注意

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」。

以下程式碼範例顯示如何使用 DeleteFunction

SDK for Java 2.x
注意

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

以下程式碼範例顯示如何使用 GetFunction

SDK for Java 2.x
注意

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

以下程式碼範例顯示如何使用 Invoke

SDK for Java 2.x
注意

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

以下程式碼範例顯示如何使用 UpdateFunctionCode

SDK for Java 2.x
注意

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

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

SDK for Java 2.x
注意

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); } }

案例

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 上的完整範例。

如要深入探索此範例的來源,請參閱 AWS 社群上的文章。

此範例中使用的服務
  • API Gateway

  • DynamoDB

  • Lambda

  • Amazon Rekognition

  • Amazon S3

  • Amazon SNS

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 中的專案。

此範例中使用的服務
  • Amazon Comprehend

  • Lambda

  • Amazon Polly

  • Amazon Textract

  • Amazon Translate

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 上的完整範例。

此範例中使用的服務
  • API Gateway

  • DynamoDB

  • Lambda

  • Amazon SNS

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 上的完整範例。

此範例中使用的服務
  • DynamoDB

  • Lambda

  • Amazon SES

  • 步驟函數

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 上的完整範例。

此範例中使用的服務
  • CloudWatch Logs

  • DynamoDB

  • EventBridge

  • Lambda

  • Amazon SNS

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 上的完整範例。

此範例中使用的服務
  • Lambda

  • Neptune

無伺服器範例

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
注意

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(); } }

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
注意

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; } }

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
注意

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())); } }

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
注意

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)); } }

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
注意

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; } }

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
注意

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); } }

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
注意

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); } } }

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
注意

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; } } }

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
注意

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); } }

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
注意

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(); } }

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
注意

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

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 上的完整範例。

此範例中使用的服務
  • API Gateway

  • DynamoDB

  • Lambda