Doubt in this program

Question

Hi folks,
I had one small doubt in the below program...
     import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class CheckingTheSession extends HttpServlet {
     public void doGet(HttpServletRequest request, HttpServletResponse response)
               throws ServletException, IOException {
          response.setContentType("text/html");
          PrintWriter out = response.getWriter();
          HttpSession session = request.getSession(false); //line 5
          if(session ==  null) {
               out.print("Old Session<br>");
               out.print("session value"+session+"<br>");
               session = request.getSession();   //line 10
          else {
               out.print("New Session");
               session = request.getSession();
               out.print("Session value: "+session+"<br>");
}The output of the above program is "session Session value: null", If we reload it again, we will be getting as "New Session Session value: org.apache.catalina.session.StandardSessionFacade@9d6065
My doubt is : When I reload it again, why it is considering as a new session , instead of an old session itself...Ofcourse at line10 , we are asking to create new session but when we reload it at line 5 again we are asking to create an old session only..So why doesn't it care line5 instead which it cares for line`10...?? Can anybody tell me the exact reason for it..

Answer 1

Looking at your code, i have noticed you are displaying session before the request session itself, as shown below.
out.print("Old Session<br>");
out.print("session value"+session+"<br>");
session = request.getSession();   //line 10try this and tell us whats' is happening;
out.print("Old Session<br>");
session = request.getSession();
out.print("session value"+session+"<br>");also i have notice you are testing for null session, while your aim is to display current session else a new one.
i think you should be testing if the session already exist like this;
//if session already exist -  display session value
if(session !=  null) {
    out.print("Old Session<br>");
    session = request.getSession();   //line 10
    out.print("session value"+session+"<br>");     
//else create a new session
else {
     out.print("New Session");
     session = request.getSession();
     out.print("Session value: "+session+"<br>");
}Hoppe this helps!