Problem passing an arrayList from a servlet to a jsp

[Raymond Champion]

Hello,

I am having trouble getting an ArrayList I created in my servlet to get passed to my JSP.

I think I have correctly put the resultset into my bean called SubmissionEvents.

From here I am trying to pass this arraylist to my JSP(homepage.jsp). My app hangs when I run it, after I login into app.

If I remove the <jsp:useBean > tags from the JSP page I am trying to display then the JSP page will display.

If you have any insight into what I am doing wrong and can help me?

Servlet code

    

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package com.cme.bioagent;

import com.mysql.jdbc.*;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author CMEBio6
 */
public class HomePageServlet extends HttpServlet {
   
    /** 
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException, ClassNotFoundException, SQLException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        ArrayList resultList = new ArrayList();


        try {
          String loginUser = "xxx";
          String loginPwd = "xxx";
          String loginUrl = "jdbc:mysql://xx.xxx.xxx.xxx.:3306/database";

          

          
          Class.forName("org.gjt.mm.mysql.Driver");
          Connection con = (Connection) DriverManager.getConnection(loginUrl, loginUser, loginPwd);
          System.out.println("got connection homepage servlet");
          Statement stm = (Statement) con.createStatement();
          String query = "SELECT submission_id FROM submission";
          ResultSet rs = stm.executeQuery(query);

          while(rs.next()){
              
              SubmissionEvents se = new SubmissionEvents();
              se.setSubmission_Id(rs.getInt("submission_id"));
              
              resultList.add(se);

              System.out.println(resultList.size());

          }
          
          request.setAttribute("seResult", resultList);
          RequestDispatcher rd = request.getRequestDispatcher("homepage.jsp");
          rd.forward(request, response);


          con.close();
          rs.close();
          stm.close();

                
                     
        } finally { 
            out.close();
        }

         
    } 

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    } 

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    }

    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>

}

The JSP (homepage.jsp)

    
<%-- 
    Document   : homepage
    Created on : Jan 12, 2010, 11:14:20 AM
    Author     : CMEBio6
--%>



<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">
<jsp:useBean id="seResult" type="com.cme.bioagent.SubmissionEvents" scope="session" />

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

        <link href="/CME-BIO_2/css/biostyle.css" rel="stylesheet" media="screen">
        <title>JSP Page</title>
    </head>
    <body>
        <img alt="BioAgent" src="/CME-BIO_2/images/bioAgentlogoblue.gif">
             <h1>Home Page</h1>
             
             <jsp:getProperty name="seResult" property="submisssion_id"/>


             
           
             <br>
    <a href ="/CME-BIO_2/fileupload.jsp">Upload File</a>

    </body>
</html>

My bean SubmissionEvents.java

    
/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package com.cme.bioagent;

/**
 *
 * @author CMEBio2
 */
class SubmissionEvents {

   public SubmissionEvents(){

    }

    int submission_Id;

     public int getSubmission_Id() {
        return submission_Id;
    }

    public void setSubmission_Id(int submission_Id) {
        this.submission_Id = submission_Id;
    }

}

[Christophe Verré]

1. Your useBean tag uses the session scope.
2. Your useBean tag expects a SubmissionEvents
3. "seResult" lives in the request scope
4. "seResult" is a List

That doesn't fit. You don't need to use useBean here. Using the EL expression ${seResult} should return you the list, which you can iterate through.