httpservelet response not returning sendError status code

Question

I am trying to determine why a webserver response that initially throws an exception in processing; then returns a 200 OK client side. The details are as follows:

• a request is sent to the webserver from the web application and if an error occurs an exception is caught and the relevant code &/or message is returned as follows:

   public void dispatchRequest(HttpServletRequest req, HttpServletResponse 
   res) 
   {
      if (method.equalsIgnoreCase("get")) {
          doGet(req, res);
      } else {
          res.sendError(HttpServletResponse.SC_NOT_IMPLEMENTED);
          return;
      }
  
   }
  
   void doGet(HttpServletRequest request, HttpServletResponse response) 
   throws 
   IOException,
   HTTPServerException {
       handleGetClient(request, response);
  
   }
  
  
  @SuppressWarnings("unchecked")
   private void handleGetClient(HttpServletRequest request, 
   HttpServletResponse 
   response)
      throws IOException, HTTPServerException {
  
      ...
  
      } catch (IOException e) {
      logger("I/O Error during playback with parameters (additional 
    parameters logged) {0}: {1}",traceParams,e.toString());
      logger(Level.FINER, "I/O Error during playback with parameters {0}: 
   {1}", parameters, e.getMessage());
      logger(Level.FINER, "I/O Error during playback with parameters {0}: 
   {1}", parameters, e);
      sendError(response, HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
  
  
     ...
  
   }
  
  
  protected void sendError(HttpServletResponse response, int errCode) {
  
  response.setContentType("text/plain");
  
  try {
     response.sendError(errCode,"ERROR");
  
  } catch (IOException e1) {
      // TODO Auto-generated catch block
      e1.printStackTrace();
  }
  
  
  }   
  

The handleGetClient method handles the process and in the event of an error throws exceptions which are caught. The method then uses the sendError method to set the error code returned and when log debugging I could see that this was set to in this specific error (500). But once the call returns to the dispatchRequest method the httpservletResponse status is actually (200). I cannot see where this happening and why. Initially I thought I could just change the method to int to return the error code but I am limited to the changes I can make on this code.

Any ideas?

Answer 1

You could try one of the following:

response.resetBuffer ();
response.setStatus (HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
response.flushBuffer ();

or if you have an error page matching the 500 code in your web.xml:

response.reset ();
response.setError (HttpServletResponse.SC_INTERNAL_SERVER_ERROR);

You could also consider using an exception mapper, for any generic error, so instead of playing yourself with the error code, you could just throw an exception which would take care of the status code return.

i.e: throw new InternalServerException ("Your message");

Answer 2

Possibly a return statement might be in the catch block that eventually ends up in normal functioning of sending response. I am only stating a possibility. More you can do is check what is being returned after the request is processed successfully from server (either after exception handling or normal functioning).