Where to write this method in my application?

[Ravi Kumar Ravuru]

Hello Folks,
I had a application which is deployed on IBM Websphere Application Server 4.0.1 Advanced Edition for MultiPlatforms.The application is abt tracking of users which consists of Jsps and EJBs.Where should i write the methods for HttpSessionListener in my application.Please give me the suggestions.
Thanks in Advance.
Ravi

[prabhat kumar]

create a class which should implement that httpsessionlistener interface and then put it in the session.
in this you can implement the methods and do work like initializations and cleanup.

[Ravi Kumar Ravuru]

Hello Prabhat,
Thanks for your response.Can u send me a piece of code related it.
Thanks in advance.
Ravi

[prabhat kumar]

Here is it. edit it to suit ur needs

  
package utils;
import java.util.*;
import java.sql.*;
import oracle.jdbc.driver.*;
import javax.servlet.*;
import javax.servlet.http.*;
/*
 * lcCon.java
 *
 * Created on February 22, 2002, 12:23 PM
 */
/**
 *
 * @author  Administrator
 * @version 1.01
 */
public class lcCon implements HttpSessionBindingListener {
    int count = 0;
    String userName = "";
    
    String password = "";
    
    String database = "";
    
    String errormessege = "";
    String userNr = "0";
    
    Connection dbCon = null;
    
    /** Creates new lcCon */
    public lcCon() {
    }
    
    public String getError(){
        return errormessege;
    }
    public void setError(String erm){
        errormessege = erm;
    }
    public void valueUnbound(HttpSessionBindingEvent e){
      System.out.println("ending session = " + e.getName() + "<BR>");
      releaseConnection();
    }//end valueUnbound()
    public lcCon(String uName, String pass, String dbase) {
        userName = uName;
        password = pass;
        database = dbase;
    }
    public lcCon(Connection con) {
        dbCon = con;
    } 
    public String getUserName() {
        return this.userName;
    }    
    
    public String getDatabase() {
        return this.database;
    }    
    
    public String getPassword(){
        return this.password;
    }
    public String getUserNr(){
        return this.userNr;
    }
    
    public void setUserNr(String userNr){
        this.userNr = userNr;
    }
    
    public Connection getConnection() {
        try{
            if(count >=90){
                if(dbCon!=null){
                    dbCon.close();
                    dbCon=null;
                }          
            }
            if(dbCon==null){
                Class.forName("oracle.jdbc.driver.OracleDriver");
                dbCon = DriverManager.getConnection("jdbc :-o	 racle:thin:@" + database, userName,password);
                System.out.println("creating new connection in session now");
                count=1;
            }else{
                count++;
                System.out.println("passing old connection in session now"+count);
            }
        }
        catch(Exception e){}
     return dbCon;   
    }
    
    public void getNewConnection() {
        try{
            if(dbCon!=null){
                dbCon.close();
                dbCon=null;
            }
            if(dbCon==null){
                Class.forName("oracle.jdbc.driver.OracleDriver");
                dbCon = DriverManager.getConnection("jdbc :-o	 racle:thin:@" + database, userName,password);
                System.out.println("closed old and created new connection in session now");
            }else{
                System.out.println("old connection is still there");
            }
        }
        catch(Exception e){}
    }
    
    public void releaseConnection(){
      try{
          if (dbCon!= null){
            dbCon.close();
          }
      }
      catch( Exception ex ){
      }
    }
    
    public void valueBound(javax.servlet.http.HttpSessionBindingEvent e) {
        System.out.println("starting session now");
    }
    
}

[Ravi Kumar Ravuru]

Hello Prabhat,
Thanks for the code.Just one more question.How do i keep this class in the session object and track the users.
Thanks in Advance.
Ravi

[Garrett Smith]

The idea is to use place this in application scope.
Use a Hashtable to store users in. Store the hashtable in the application scope. You can modify the code in the previous post to do this.
Then when a session expires, you have to have an event hook to log them out. You do this by implementing the HttpSessionListener interface. Below is a sample of this.

package com.dhtmlkitchen;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.naming.NamingException;
import com.dhtmlkitchen.reg.BasicUser;
import com.dhtmlkitchen.reg.db.Database;

public class SessionListenerImpl implements HttpSessionListener {
public void sessionCreated(HttpSessionEvent event) {
// empty.
}

public void sessionDestroyed(HttpSessionEvent event) {

HttpSession session = event.getSession();

BasicUser user = (BasicUser)session.getAttribute("user");

if(user != null){
session.removeAttribute("user");
Database.logout(user.getUsername());
}
}
}