使用 SDK 的 Java 2.x 的 Step Functions 示例 - 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 SDK 的 Java 2.x 的 Step Functions 示例

下列程式碼範例說明如何使用 AWS SDK for Java 2.x 與 Step Functions 來執行動作及實作常見案例。

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和跨服務範例中查看內容中的動作。

Scenarios (案例) 是向您展示如何呼叫相同服務中的多個函數來完成特定任務的程式碼範例。

每個範例都包含一個連結 GitHub,您可以在其中找到如何在內容中設定和執行程式碼的指示。

開始使用

下列程式碼範例會示範如何開始使用 Step Functions 式。

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

你好的 Java 版本。

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.sfn.SfnClient; import software.amazon.awssdk.services.sfn.model.ListStateMachinesResponse; import software.amazon.awssdk.services.sfn.model.SfnException; import software.amazon.awssdk.services.sfn.model.StateMachineListItem; import java.util.List; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class ListStateMachines { public static void main(String[] args) { Region region = Region.US_EAST_1; SfnClient sfnClient = SfnClient.builder() .region(region) .build(); listMachines(sfnClient); sfnClient.close(); } public static void listMachines(SfnClient sfnClient) { try { ListStateMachinesResponse response = sfnClient.listStateMachines(); List<StateMachineListItem> machines = response.stateMachines(); for (StateMachineListItem machine : machines) { System.out.println("The name of the state machine is: " + machine.name()); System.out.println("The ARN value is : " + machine.stateMachineArn()); } } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考ListStateMachines中的。

動作

下列程式碼範例會示範如何使用CreateActivity

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static String createActivity(SfnClient sfnClient, String activityName) { try { CreateActivityRequest activityRequest = CreateActivityRequest.builder() .name(activityName) .build(); CreateActivityResponse response = sfnClient.createActivity(activityRequest); return response.activityArn(); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考CreateActivity中的。

下列程式碼範例會示範如何使用CreateStateMachine

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static String createMachine(SfnClient sfnClient, String roleARN, String stateMachineName, String json) { try { CreateStateMachineRequest machineRequest = CreateStateMachineRequest.builder() .definition(json) .name(stateMachineName) .roleArn(roleARN) .type(StateMachineType.STANDARD) .build(); CreateStateMachineResponse response = sfnClient.createStateMachine(machineRequest); return response.stateMachineArn(); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考CreateStateMachine中的。

下列程式碼範例會示範如何使用DeleteActivity

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static void deleteActivity(SfnClient sfnClient, String actArn) { try { DeleteActivityRequest activityRequest = DeleteActivityRequest.builder() .activityArn(actArn) .build(); sfnClient.deleteActivity(activityRequest); System.out.println("You have deleted " + actArn); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考DeleteActivity中的。

下列程式碼範例會示範如何使用DeleteStateMachine

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static void deleteMachine(SfnClient sfnClient, String stateMachineArn) { try { DeleteStateMachineRequest deleteStateMachineRequest = DeleteStateMachineRequest.builder() .stateMachineArn(stateMachineArn) .build(); sfnClient.deleteStateMachine(deleteStateMachineRequest); DescribeStateMachineRequest describeStateMachine = DescribeStateMachineRequest.builder() .stateMachineArn(stateMachineArn) .build(); while (true) { DescribeStateMachineResponse response = sfnClient.describeStateMachine(describeStateMachine); System.out.println("The state machine is not deleted yet. The status is " + response.status()); Thread.sleep(3000); } } catch (SfnException | InterruptedException e) { System.err.println(e.getMessage()); } System.out.println(stateMachineArn + " was successfully deleted."); }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考DeleteStateMachine中的。

下列程式碼範例會示範如何使用DescribeExecution

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static void describeExe(SfnClient sfnClient, String executionArn) { try { DescribeExecutionRequest executionRequest = DescribeExecutionRequest.builder() .executionArn(executionArn) .build(); String status = ""; boolean hasSucceeded = false; while (!hasSucceeded) { DescribeExecutionResponse response = sfnClient.describeExecution(executionRequest); status = response.statusAsString(); if (status.compareTo("RUNNING") == 0) { System.out.println("The state machine is still running, let's wait for it to finish."); Thread.sleep(2000); } else if (status.compareTo("SUCCEEDED") == 0) { System.out.println("The Step Function workflow has succeeded"); hasSucceeded = true; } else { System.out.println("The Status is neither running or succeeded"); } } System.out.println("The Status is " + status); } catch (SfnException | InterruptedException 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DescribeExecution中的。

下列程式碼範例會示範如何使用DescribeStateMachine

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static void describeStateMachine(SfnClient sfnClient, String stateMachineArn) { try { DescribeStateMachineRequest stateMachineRequest = DescribeStateMachineRequest.builder() .stateMachineArn(stateMachineArn) .build(); DescribeStateMachineResponse response = sfnClient.describeStateMachine(stateMachineRequest); System.out.println("The name of the State machine is " + response.name()); System.out.println("The status of the State machine is " + response.status()); System.out.println("The ARN value of the State machine is " + response.stateMachineArn()); System.out.println("The role ARN value is " + response.roleArn()); } catch (SfnException e) { System.err.println(e.getMessage()); } }

下列程式碼範例會示範如何使用GetActivityTask

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static List<String> getActivityTask(SfnClient sfnClient, String actArn) { List<String> myList = new ArrayList<>(); GetActivityTaskRequest getActivityTaskRequest = GetActivityTaskRequest.builder() .activityArn(actArn) .build(); GetActivityTaskResponse response = sfnClient.getActivityTask(getActivityTaskRequest); myList.add(response.taskToken()); myList.add(response.input()); return myList; } /// <summary> /// Stop execution of a Step Functions workflow. /// </summary> /// <param name="executionArn">The Amazon Resource Name (ARN) of /// the Step Functions execution to stop.</param> /// <returns>A Boolean value indicating the success of the action.</returns> public async Task<bool> StopExecution(string executionArn) { var response = await _amazonStepFunctions.StopExecutionAsync(new StopExecutionRequest { ExecutionArn = executionArn }); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考GetActivityTask中的。

下列程式碼範例會示範如何使用ListActivities

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.sfn.SfnClient; import software.amazon.awssdk.services.sfn.model.ListActivitiesRequest; import software.amazon.awssdk.services.sfn.model.ListActivitiesResponse; import software.amazon.awssdk.services.sfn.model.SfnException; import software.amazon.awssdk.services.sfn.model.ActivityListItem; import java.util.List; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class ListActivities { public static void main(String[] args) { Region region = Region.US_EAST_1; SfnClient sfnClient = SfnClient.builder() .region(region) .build(); listAllActivites(sfnClient); sfnClient.close(); } public static void listAllActivites(SfnClient sfnClient) { try { ListActivitiesRequest activitiesRequest = ListActivitiesRequest.builder() .maxResults(10) .build(); ListActivitiesResponse response = sfnClient.listActivities(activitiesRequest); List<ActivityListItem> items = response.activities(); for (ActivityListItem item : items) { System.out.println("The activity ARN is " + item.activityArn()); System.out.println("The activity name is " + item.name()); } } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考ListActivities中的。

下列程式碼範例會示範如何使用ListExecutions

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static void getExeHistory(SfnClient sfnClient, String exeARN) { try { GetExecutionHistoryRequest historyRequest = GetExecutionHistoryRequest.builder() .executionArn(exeARN) .maxResults(10) .build(); GetExecutionHistoryResponse historyResponse = sfnClient.getExecutionHistory(historyRequest); List<HistoryEvent> events = historyResponse.events(); for (HistoryEvent event : events) { System.out.println("The event type is " + event.type().toString()); } } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考ListExecutions中的。

下列程式碼範例會示範如何使用ListStateMachines

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

import software.amazon.awssdk.regions.Region; import software.amazon.awssdk.services.sfn.SfnClient; import software.amazon.awssdk.services.sfn.model.ListStateMachinesResponse; import software.amazon.awssdk.services.sfn.model.SfnException; import software.amazon.awssdk.services.sfn.model.StateMachineListItem; import java.util.List; /** * Before running this Java V2 code example, set up your development * environment, including your credentials. * * For more information, see the following documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html */ public class ListStateMachines { public static void main(String[] args) { Region region = Region.US_EAST_1; SfnClient sfnClient = SfnClient.builder() .region(region) .build(); listMachines(sfnClient); sfnClient.close(); } public static void listMachines(SfnClient sfnClient) { try { ListStateMachinesResponse response = sfnClient.listStateMachines(); List<StateMachineListItem> machines = response.stateMachines(); for (StateMachineListItem machine : machines) { System.out.println("The name of the state machine is: " + machine.name()); System.out.println("The ARN value is : " + machine.stateMachineArn()); } } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考ListStateMachines中的。

下列程式碼範例會示範如何使用SendTaskSuccess

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static void sendTaskSuccess(SfnClient sfnClient, String token, String json) { try { SendTaskSuccessRequest successRequest = SendTaskSuccessRequest.builder() .taskToken(token) .output(json) .build(); sfnClient.sendTaskSuccess(successRequest); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考SendTaskSuccess中的。

下列程式碼範例會示範如何使用StartExecution

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

public static String startWorkflow(SfnClient sfnClient, String stateMachineArn, String jsonEx) { UUID uuid = UUID.randomUUID(); String uuidValue = uuid.toString(); try { StartExecutionRequest executionRequest = StartExecutionRequest.builder() .input(jsonEx) .stateMachineArn(stateMachineArn) .name(uuidValue) .build(); StartExecutionResponse response = sfnClient.startExecution(executionRequest); return response.executionArn(); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; }
  • 如需 API 詳細資訊,請參閱 AWS SDK for Java 2.x API 參考StartExecution中的。

案例

以下程式碼範例顯示做法:

  • 建立活動。

  • 從 Amazon States 語言定義建立狀態機,其中包含先前建立的活動作為一個步驟。

  • 運行狀態機並使用用戶輸入響應活動。

  • 在執行完成後取得最終狀態和輸出,然後清理資源。

適用於 Java 2.x 的 SDK
注意

還有更多關於 GitHub。尋找完整範例,並了解如何在AWS 設定和執行程式碼範例儲存庫

/** * You can obtain the JSON file to create a state machine in the following * GitHub location. * * https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/resources/sample_files * * To run this code example, place the chat_sfn_state_machine.json file into * your project's resources folder. * * Also, set up your development environment, including your credentials. * * For information, see this documentation topic: * * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html * * This Java code example performs the following tasks: * * 1. Creates an activity. * 2. Creates a state machine. * 3. Describes the state machine. * 4. Starts execution of the state machine and interacts with it. * 5. Describes the execution. * 6. Delete the activity. * 7. Deletes the state machine. */ public class StepFunctionsScenario { public static final String DASHES = new String(new char[80]).replace("\0", "-"); public static void main(String[] args) throws Exception { final String usage = """ Usage: <roleARN> <activityName> <stateMachineName> Where: roleName - The name of the IAM role to create for this state machine. activityName - The name of an activity to create. stateMachineName - The name of the state machine to create. """; if (args.length != 3) { System.out.println(usage); System.exit(1); } String roleName = args[0]; String activityName = args[1]; String stateMachineName = args[2]; String polJSON = "{\n" + " \"Version\": \"2012-10-17\",\n" + " \"Statement\": [\n" + " {\n" + " \"Sid\": \"\",\n" + " \"Effect\": \"Allow\",\n" + " \"Principal\": {\n" + " \"Service\": \"states.amazonaws.com\"\n" + " },\n" + " \"Action\": \"sts:AssumeRole\"\n" + " }\n" + " ]\n" + "}"; Scanner sc = new Scanner(System.in); boolean action = false; Region region = Region.US_EAST_1; SfnClient sfnClient = SfnClient.builder() .region(region) .build(); Region regionGl = Region.AWS_GLOBAL; IamClient iam = IamClient.builder() .region(regionGl) .build(); System.out.println(DASHES); System.out.println("Welcome to the AWS Step Functions example scenario."); System.out.println(DASHES); System.out.println(DASHES); System.out.println("1. Create an activity."); String activityArn = createActivity(sfnClient, activityName); System.out.println("The ARN of the activity is " + activityArn); System.out.println(DASHES); // Get JSON to use for the state machine and place the activityArn value into // it. InputStream input = StepFunctionsScenario.class.getClassLoader() .getResourceAsStream("chat_sfn_state_machine.json"); ObjectMapper mapper = new ObjectMapper(); JsonNode jsonNode = mapper.readValue(input, JsonNode.class); String jsonString = mapper.writeValueAsString(jsonNode); // Modify the Resource node. ObjectMapper objectMapper = new ObjectMapper(); JsonNode root = objectMapper.readTree(jsonString); ((ObjectNode) root.path("States").path("GetInput")).put("Resource", activityArn); // Convert the modified Java object back to a JSON string. String stateDefinition = objectMapper.writeValueAsString(root); System.out.println(stateDefinition); System.out.println(DASHES); System.out.println("2. Create a state machine."); String roleARN = createIAMRole(iam, roleName, polJSON); String stateMachineArn = createMachine(sfnClient, roleARN, stateMachineName, stateDefinition); System.out.println("The ARN of the state machine is " + stateMachineArn); System.out.println(DASHES); System.out.println(DASHES); System.out.println("3. Describe the state machine."); describeStateMachine(sfnClient, stateMachineArn); System.out.println("What should ChatSFN call you?"); String userName = sc.nextLine(); System.out.println("Hello " + userName); System.out.println(DASHES); System.out.println(DASHES); // The JSON to pass to the StartExecution call. String executionJson = "{ \"name\" : \"" + userName + "\" }"; System.out.println(executionJson); System.out.println("4. Start execution of the state machine and interact with it."); String runArn = startWorkflow(sfnClient, stateMachineArn, executionJson); System.out.println("The ARN of the state machine execution is " + runArn); List<String> myList; while (!action) { myList = getActivityTask(sfnClient, activityArn); System.out.println("ChatSFN: " + myList.get(1)); System.out.println(userName + " please specify a value."); String myAction = sc.nextLine(); if (myAction.compareTo("done") == 0) action = true; System.out.println("You have selected " + myAction); String taskJson = "{ \"action\" : \"" + myAction + "\" }"; System.out.println(taskJson); sendTaskSuccess(sfnClient, myList.get(0), taskJson); } System.out.println(DASHES); System.out.println(DASHES); System.out.println("5. Describe the execution."); describeExe(sfnClient, runArn); System.out.println(DASHES); System.out.println(DASHES); System.out.println("6. Delete the activity."); deleteActivity(sfnClient, activityArn); System.out.println(DASHES); System.out.println(DASHES); System.out.println("7. Delete the state machines."); deleteMachine(sfnClient, stateMachineArn); System.out.println(DASHES); System.out.println(DASHES); System.out.println("The AWS Step Functions example scenario is complete."); System.out.println(DASHES); } public static String createIAMRole(IamClient iam, String rolename, String polJSON) { try { CreateRoleRequest request = CreateRoleRequest.builder() .roleName(rolename) .assumeRolePolicyDocument(polJSON) .description("Created using the AWS SDK for Java") .build(); CreateRoleResponse response = iam.createRole(request); return response.role().arn(); } catch (IamException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; } public static void describeExe(SfnClient sfnClient, String executionArn) { try { DescribeExecutionRequest executionRequest = DescribeExecutionRequest.builder() .executionArn(executionArn) .build(); String status = ""; boolean hasSucceeded = false; while (!hasSucceeded) { DescribeExecutionResponse response = sfnClient.describeExecution(executionRequest); status = response.statusAsString(); if (status.compareTo("RUNNING") == 0) { System.out.println("The state machine is still running, let's wait for it to finish."); Thread.sleep(2000); } else if (status.compareTo("SUCCEEDED") == 0) { System.out.println("The Step Function workflow has succeeded"); hasSucceeded = true; } else { System.out.println("The Status is neither running or succeeded"); } } System.out.println("The Status is " + status); } catch (SfnException | InterruptedException e) { System.err.println(e.getMessage()); System.exit(1); } } public static void sendTaskSuccess(SfnClient sfnClient, String token, String json) { try { SendTaskSuccessRequest successRequest = SendTaskSuccessRequest.builder() .taskToken(token) .output(json) .build(); sfnClient.sendTaskSuccess(successRequest); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static List<String> getActivityTask(SfnClient sfnClient, String actArn) { List<String> myList = new ArrayList<>(); GetActivityTaskRequest getActivityTaskRequest = GetActivityTaskRequest.builder() .activityArn(actArn) .build(); GetActivityTaskResponse response = sfnClient.getActivityTask(getActivityTaskRequest); myList.add(response.taskToken()); myList.add(response.input()); return myList; } public static void deleteActivity(SfnClient sfnClient, String actArn) { try { DeleteActivityRequest activityRequest = DeleteActivityRequest.builder() .activityArn(actArn) .build(); sfnClient.deleteActivity(activityRequest); System.out.println("You have deleted " + actArn); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } } public static void describeStateMachine(SfnClient sfnClient, String stateMachineArn) { try { DescribeStateMachineRequest stateMachineRequest = DescribeStateMachineRequest.builder() .stateMachineArn(stateMachineArn) .build(); DescribeStateMachineResponse response = sfnClient.describeStateMachine(stateMachineRequest); System.out.println("The name of the State machine is " + response.name()); System.out.println("The status of the State machine is " + response.status()); System.out.println("The ARN value of the State machine is " + response.stateMachineArn()); System.out.println("The role ARN value is " + response.roleArn()); } catch (SfnException e) { System.err.println(e.getMessage()); } } public static void deleteMachine(SfnClient sfnClient, String stateMachineArn) { try { DeleteStateMachineRequest deleteStateMachineRequest = DeleteStateMachineRequest.builder() .stateMachineArn(stateMachineArn) .build(); sfnClient.deleteStateMachine(deleteStateMachineRequest); DescribeStateMachineRequest describeStateMachine = DescribeStateMachineRequest.builder() .stateMachineArn(stateMachineArn) .build(); while (true) { DescribeStateMachineResponse response = sfnClient.describeStateMachine(describeStateMachine); System.out.println("The state machine is not deleted yet. The status is " + response.status()); Thread.sleep(3000); } } catch (SfnException | InterruptedException e) { System.err.println(e.getMessage()); } System.out.println(stateMachineArn + " was successfully deleted."); } public static String startWorkflow(SfnClient sfnClient, String stateMachineArn, String jsonEx) { UUID uuid = UUID.randomUUID(); String uuidValue = uuid.toString(); try { StartExecutionRequest executionRequest = StartExecutionRequest.builder() .input(jsonEx) .stateMachineArn(stateMachineArn) .name(uuidValue) .build(); StartExecutionResponse response = sfnClient.startExecution(executionRequest); return response.executionArn(); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; } public static String createMachine(SfnClient sfnClient, String roleARN, String stateMachineName, String json) { try { CreateStateMachineRequest machineRequest = CreateStateMachineRequest.builder() .definition(json) .name(stateMachineName) .roleArn(roleARN) .type(StateMachineType.STANDARD) .build(); CreateStateMachineResponse response = sfnClient.createStateMachine(machineRequest); return response.stateMachineArn(); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; } public static String createActivity(SfnClient sfnClient, String activityName) { try { CreateActivityRequest activityRequest = CreateActivityRequest.builder() .name(activityName) .build(); CreateActivityResponse response = sfnClient.createActivity(activityRequest); return response.activityArn(); } catch (SfnException e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; } }