@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); } }