Get Mapping Template from API Gateway as JSON in AWS Lambda Java Project

Thanks to Ka Hou leong for the direction, I've solved with the following:

1) Added dependency in Maven for aws-serverless-java-container

<dependency>    <groupId>com.amazonaws.serverless</groupId>    <artifactId>aws-serverless-java-container-core</artifactId>    <version>0.4</version></dependency>

2) Modified my LambdaFunctionHandler class to use AwsProxyRequest and AwsProxyResponse:

import com.amazonaws.serverless.proxy.internal.model.AwsProxyRequest;import com.amazonaws.serverless.proxy.internal.model.AwsProxyResponse;import com.amazonaws.services.lambda.runtime.Context;import com.amazonaws.services.lambda.runtime.RequestHandler;public class LambdaFunctionHandler implements RequestHandler<AwsProxyRequest, Object> {    public Object handleRequest(AwsProxyRequest input, Context context) {        AwsProxyResponse response = new AwsProxyResponse();        String resourcePath = input.getRequestContext().getResourcePath();        response.setStatusCode(200);        response.setBody(resourcePath);    return response;    }}

3) Modified my API Gateway method Integration Request settings to Use Lambda Proxy Integration.

From here I have access to everything in the input object as an AwsProxyRequest, and will manipulate response as an AwsProxyResponse with anything I want to respond with.

You can write your own POJO to match the request from API Gateway, then you will be able to access the resource path from a getter.

POJOs example:

public class LambdaFunctionHandler implements RequestHandler<Object, Object> {    @Override    public Object handleRequest(AwsProxyRequest input, Context context) {        String resourcePath = input.getRequestContext().getResourcePath();        return resourcePath;    }}public class AwsProxyRequest {    //-------------------------------------------------------------    // Variables - Private    //-------------------------------------------------------------    private ApiGatewayRequestContext requestContext;    ....    //-------------------------------------------------------------    // Methods - Getter/Setter    //-------------------------------------------------------------    public ApiGatewayRequestContext getRequestContext() {        return requestContext;    }    public void setRequestContext(ApiGatewayRequestContext requestContext) {        this.requestContext = requestContext;    }    ....}public class ApiGatewayRequestContext {    //-------------------------------------------------------------    // Variables - Private    //-------------------------------------------------------------    private String resourcePath;    ...    //-------------------------------------------------------------    // Methods - Getter/Setter    //-------------------------------------------------------------    public String getResourcePath() {        return resourcePath;    }    public void setResourcePath(String resourcePath) {        this.resourcePath = resourcePath;    }    ....}

If you want the full proxy request POJO, you can find them from here.