Using Lambda To Trigger a State Function

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publicclassStepFnExecutorLambdaimplements RequestHandler<String, Boolean>{

private AWSStepFunctions awsStepFunctionsClient;

publicStepFnExecutorLambda(){
        AWSCredentials awsCredentials =new BasicAWSCredentials("AccessKey","SecretKey");
        AWSCredentialsProvider awsCredentialsProvider =new AWSStaticCredentialsProvider(awsCredentials);

        ClientConfiguration clientConfiguration =new ClientConfiguration();
        clientConfiguration.setClientExecutionTimeout(2*60*1000);//2 mins
        awsStepFunctionsClient = AWSStepFunctionsClient.builder()
.withCredentials(awsCredentialsProvider)
.withRegion(Regions.US_EAST_1)
.withClientConfiguration(clientConfiguration)
.build();
}

@Override
public Boolean handleRequest(String input, Context context){
        LambdaLogger logger = context.getLogger();
        logger.log("In Handler: Executing "+ context.getFunctionName()

                   +", "+ context.getFunctionVersion());
        logger.log(input);//This input is not really used now

// Start state machine
        StartExecutionRequest startExecutionRequest =new StartExecutionRequest();
startExecutionRequest.setStateMachineArn("arn:aws:states:us-east-1:360767005075:stateMachine:TestStateMachine");

        StartExecutionResult startExecutionResult =

awsStepFunctionsClient.startExecution(startExecutionRequest);
        String executionArn = startExecutionResult.getExecutionArn();
        logger.log("Execution started with arn "+ executionArn);

//Check Step Execution Completion
        String status ="";
do{
            DescribeExecutionRequest describeExecutionRequest =

                     new DescribeExecutionRequest();
            describeExecutionRequest.setExecutionArn(executionArn);
            DescribeExecutionResult describeExecutionResult =

awsStepFunctionsClient.describeExecution(describeExecutionRequest);
            status = describeExecutionResult.getStatus();
            logger.log("Execution with arn "+ executionArn +" returned status "+ status);
}while("RUNNING".equals(status));
//return execution arn
        logger.log("Final Status "+ executionArn +" : "+ status);
return"SUCCEEDED".equals(status);
}
}

Amazon Resource Names (ARNs) uniquely identify AWS resources. We require an 

ARN when you need to specify a resource unambiguously across all of AWS, 

such as in IAM policies, Amazon Relational Database Service (Amazon RDS) tags,

and API calls.