title: nullpointer exception with amazonhttpclient
body: <p>I have put this in sample main class when I execute it I am getting nullpointerexception.it's not giving more details.</p>
  
  <p>My intentions are I am having AWS lambda function which will trigger the above code when any node fails
  I am calling a post request in the above code but it's not working
  could you please anyone guide me to the write steps or links for this amazonhttpclient related queries.</p>
  
  <pre><code>ClientConfiguration configuration = new ClientConfiguration();
      configuration.setMaxErrorRetry(3);
      configuration.setConnectionTimeout(501000);
      configuration.setSocketTimeout(501000);
      configuration.setProtocol(Protocol.HTTP);
              AmazonHttpClient httpClient = new AmazonHttpClient(
                      configuration);
              RequestExecutionBuilder httpRequestBuilder = httpClient.requestExecutionBuilder();
              @SuppressWarnings("rawtypes")
              String url = "http://localhost:8080/spring4upgrade/processFailureNode"; 
              AmazonWebServiceRequest amazonWebServiceRequest = new AmazonWebServiceRequest() {
              };
  
              Request paramRequest = new DefaultRequest(amazonWebServiceRequest,"execute-api");
              paramRequest.setEndpoint(URI.create(url));
              paramRequest.setHttpMethod(HttpMethodName.POST);
              paramRequest.addParameter("sgroup", "xyz");
              paramRequest.addParameter("host", "localhost");
              paramRequest.addParameter("port", "8080");
              httpRequestBuilder.request(paramRequest);
              httpRequestBuilder.execute();
  </code></pre>