package com.serverless; import java.util.Collections; import java.util.Map; import com.amazonaws.services.lambda.runtime.Context; import com.amazonaws.services.lambda.runtime.RequestHandler; public class Handler implements RequestHandler, ApiGatewayResponse> { @Override public ApiGatewayResponse handleRequest(Map input, Context context) { Response responseBody = new Response("Hello world!", null); return ApiGatewayResponse.builder() .setStatusCode(200) .setObjectBody(responseBody) .setHeaders(Collections.singletonMap("X-Powered-By", "AWS Lambda & serverless")) .build(); } }