ObjectOutputStream problem

Question

hi, All, I try to send the Vector to the applet from Servlet, but when I insert the code:
the ObjectOutputStream objin = new ObjectOutputStream(res.getOutputStream());
there are many error comes out, can any one tell me what's wrong with this line of code?
Error message :
java.lang.IllegalStateException: getWriter() has already been called for this response
at org.apache.coyote.tomcat4.CoyoteResponse.getOutputStream(CoyoteResponse.java:586)
at org.apache.coyote.tomcat4.CoyoteResponseFacade.getOutputStream(CoyoteResponseFacade.java:158)
     at DBConnect.doGet(DBConnect.java:60)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.catalina.servlets.InvokerServlet.serveRequest(InvokerServlet.java:466)
     at org.apache.catalina.servlets.InvokerServlet.doGet(InvokerServlet.java:180)

Answer 1

Hi all if i remove the PrintWriter also problem is coming below my code is there
package com.base.eterna.handlers;
import java.io.IOException;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.PreparedStatement;
import java.sql.ResultSetMetaData;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.base.eterna.interfaces.RequestHandler;
import com.base.eterna.util.database.DatabaseConnection;
import java.sql.*;
import javax.servlet.ServletOutputStream;
import java.io.InputStream;
import java.io.*;
*@Author Abhinay
*@ Created on 10/01/2008 happy new year
*@ Description: Request handler class which exports entity type details to an excel file
public class ExportToExcelRequestHandler extends DatabaseConnection implements RequestHandler
HttpSession session=null;
//PrintWriter out=null;
Connection con=null;
ResultSet rs=null;
Statement st=null;
PreparedStatement stmt=null;
                    ResultSetMetaData colNames=null;
                    List<String> leaveTypes=null;
                    List<String> empIds=null;
                    int requestFor=0;
                    String query=null,query2=null, entitytypeName, entitytypeDesc;
String entity1="",entity2="", query1=null;
                    Blob image=null;
                    ServletOutputStream output=null;
                    InputStream input=null;
                    Blob in;
                    // int size;
public ExportToExcelRequestHandler()
          super();
public String processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException,IOException,Exception
try
response.setHeader("Cache-Control","no-cache"); // forces browser to retrieve fresh page only
response.setHeader("Cache-Control","no-store"); // forces cache not to store pages
response.setDateHeader("Expires",-1); // lets proxy cache sees only stale pages
response.setHeader("Pragma","no-cache"); // HTTP 1.1 backward compatibility
                         response.reset();
          response.setContentType("image/jpeg");
          response.addHeader("Content-Disposition","filename=42.jpeg");
                         //out=response.getWriter();
session=request.getSession(true);
                         byte[] buff=null;
if((String)session.getAttribute("userId")==null)
request.setAttribute("expired","Sorry! your session has expired.You have to relogin to access your account.");
return ("index.jsp");
                         st=getStatement();
                    requestFor=Integer.parseInt(request.getParameter("export") );
                    switch(requestFor)
                         case 1: query1="Select image from imageData ";
                              // out.print("\t\tFOLLOWING ARE THE Entity Type \n\n");
                         //out.print("Entity Type Name"+"\t"+"Description"+"\t"+"LastUpdatedBy"+"\t"+"LastUpdatedOn");
                                                                 rs=st.executeQuery(query1);
                                                                 while(rs.next())
                                                                      //     out.println(2/0);
                                                                      image = rs.getBlob("image");
                                                                      // tell it we are sending a jpeg image as response.
//response.setContentType("image/jpeg");
//Blob image = rs.getBlob("Binary_Photo");
// setup the streams to process blob
input = image.getBinaryStream();
                                                       output = response.getOutputStream();
                                                            //out.println(2/0);
// set read buffer size
byte[] rb = new byte[1024];
int ch = 0;
// process blob
while ((ch=input.read(rb)) != -1)
output.write(rb, 0, ch);
break;
// default : break;
                         //out.flush();
                              return ("homepage.jsp");
} // End of the try block
catch(SQLException se)
throw se;
catch(Exception e)
throw e;
finally
closeResources();
                         query=query1=null;
}// End of the process request method
} // End of the request handler class
This is the exception is coming
Error Message: getWriter() has already been called for this response
Cause: null
java.lang.IllegalStateException: getWriter() has already been called for this response
So please if anybody have an idea please tell me