newbie question : HttpSessionBindingListener Interface

[pincopallo_it]

I got a servlet and and I d like to use the interface
HttpSessionBindingListener to check when session expires and give a
message to the user
I did not find examples about how to use it...
Anyone can help ?
thats what I do:
1) public class GUIControllerRead extends HttpServlet
public class GUIControllerRead extends HttpServlet implements
HttpSessionBindingListener // I add the interface in this way
2)I added this code
HttpSessionBindingEvent firstry= new HttpSessionBindingEvent;

public void valueUnbound(firstry) {
System.out.println ("Expired session " );
}
public void valueBound(firstry) {
System.out.println ("Active session " );
}

protected void processRequest(HttpServletRequest request,
HttpServletResponse response)
throws ServletException
{

int id_eins;

session = request.getSession();
request.setAttribute("guicontroller",
this.getClass().getName());

Enumeration en = request.getParameterNames();
while (en.hasMoreElements()) {
...

Thanks
Gianni

 

[stefanomnn]

Hi, Gianni, it's simple! you make a class like this

package mypack;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionBindingEvent;

public class MySessionListener implements
javax.servlet.http.HttpSessionListener,
javax.servlet.http.HttpSessionAttributeListener
{
private String name = null;
private HttpSession session = null;

public void sessionCreated(HttpSessionEvent event)
{
session = event.getSession();
}

public void sessionDestroyed(HttpSessionEvent event)
{
session = event.getSession();
/* handle event */
}

public void attributeAdded(HttpSessionBindingEvent event)
{
name = event.getName();
session = event.getSession();
}

public void attributeRemoved(HttpSessionBindingEvent event)
{
name = event.getName();
session = event.getSession();
}

public void attributeReplaced(HttpSessionBindingEvent event)
{
name = event.getName();
session = event.getSession();
}
}

then, in web.xml, add this (before declaring your servlet):

<listener>
<listener-class>mypack.MySessionListener</listener-class>
</listener>

i hope i helped you!