@Override
 public void doGet(HttpServletRequest request, HttpServletResponse response)
     throws ServletException, IOException {
   String callback;
   ServletUtils.setJsonContentType(response);
   ResponsePayload responsePayload = new ResponsePayload();
   try {
     callback = ServletUtils.getCallbackParameter(request);
     try {
       String action = ServletUtils.getSelectActionParameter(request);
       executeAction(action, request, responsePayload);
     } catch (AWInvalidParameterException
         | AWNoSuchEntityException
         | AWInvalidResourceIdException ex) {
       responsePayload.addError(ex.getMessage());
     } finally {
       ServletUtils.printResponse(response, callback, mResponseFormatter.toJson(responsePayload));
     }
   } catch (AWInvalidParameterException ex) {
     responsePayload.addError(ex.getMessage());
     ServletUtils.setResponseBody(response, mResponseFormatter.toJson(responsePayload));
     ServletUtils.setResponseClientError(response);
   }
 }