Clearing Request / Response Objects

Question

Hi,
I have a File Upload Screen where I have validated for the File Content Length to be within 3 MB. Now I call the MultiPartRequest Reusable Object provided by Jason Hunter from a Servlet. Now as long as the file (which I am uploading) size is less than 3 MB, the Screen seems to be very fast. The Problem that I face is as follows:
I am trying to upload a file of 5 MB file size. Since my validation is in the Reusable MultiPartRequest Object, an Exception is thrown out of this Object and caught in the Servlet.
Scenerio 1:
Now from the Servlet I was using RequestDispatcher to forward to the Error Page. Since when I forward like this, the same request Object is send back to the Client which increases the response time. For me the Screen crashes due to Browser Time out.
Scenerio 2:
Now from the Servlet I tried using response.sendRedirect to the Error Page. Still the response time is more but comparatively less than the Scenerio 1.
My Question:
1. Is there a way to clear the contents of the Request and Response Object so that the response time to the client is reduced?
2. I think what I am asking is not possible. But still taking a chance is not a mistake. Is there a way to create a new Request or Response Object? I believe we (as an application developer) have no control over this as the Application Server will have control over this.
Any help or tips would be appreciated.
Thanks and regards,
Pazhanikanthan. P

Answer 1

Hi,
Thanks for your response. I do agree it is not the problem with the Multipart Classes.
Kindly see the following URL for the differences between RequestDispatcher.forward () and response.sendRedirect ().
http://www.theserverside.com/discussion/thread.jsp?thread_id=742
Here they say that "the request and response objects remain the same both from where the forward call was made and the resource which was called." Is this wrong?
More over I found that MultipartParser doesnt improve the performance very drastically over the MultipartRequestObject ...
Please find attached the time I have calculated in between the time I forward / redirect in Servlet to the time when the response is painted in the Screen.
Using Send Redirect Method (in Seconds)
=======================================
MultipartParser.java
170.156
MultipartRequestObject.java
172.422
Using requestDispatcher.forward () (in seconds)
==============================================
MultipartParser.java
Browser Times out
MultipartRequestObject.java
Browser Times out
Here is my code:
public void doPost(HttpServletRequest request,HttpServletResponse response)
     throws ServletException, IOException
     HttpSession objSession = request.getSession(true);
     String strFilePath = "D:\\uploads";
     String strFilename = "";
     MultipartRequestObject clsMulti;
     MultipartParser clsMultiParser;
     try
          System.out.println ("Action is :" + request.getParameter ("hdAction"));
          if (request.getParameter ("hdAction") == null)
               clsMultiParser = new MultipartParser (request, 1*1024*1024);
               Part objPart = clsMultiParser.readNextPart ();
               if (objPart != null)
                    FilePart objFilePart = (FilePart) objPart;
                    System.out.println ("The File Name is : " +objFilePart.getFileName ());
                    objFilePart.writeTo (new File (strFilePath + File.separatorChar + objFilePart.getFileName ()));
               clsMulti = new MultipartRequestObject (request, strFilePath, 1*1024*1024);
               Enumeration enumFiles=clsMulti.getFileNames();
               while(enumFiles.hasMoreElements())
                    String strName=(String)enumFiles.nextElement();
                    strFilename = clsMulti.getFilesystemName(strName);
     catch(Exception expGeneral)
          System.out.println ("" + new java.util.Date () + "----" + expGeneral.getMessage ());
          objSession.setAttribute ("MESSAGE", expGeneral.getMessage ());
     try
          System.out.println (1);
          RequestDispatcher dispatcher = this.getServletContext().getRequestDispatcher("/Upload.jsp");
          System.out.println (2);
          java.util.Date dt1 = new java.util.Date ();
          System.out.println (dt1.getTime ());
          dispatcher.forward(request, response);
          System.out.println (3);
          java.util.Date dt1 = new java.util.Date ();
          System.out.println (1);
          System.out.println (dt1.getTime ());
          response.reset ();
          System.out.println (2);
          response.sendRedirect ("Upload.jsp");
          System.out.println (3);
          return;
     catch (Exception e)
          e.printStackTrace ();
For testing pupose I have commented some part of the code.
Thanks and regards,
Pazhanikanthan. P