What is HttpSession in Servlet?

What is HttpSession in Servlet?

public interface HttpSession. Provides a way to identify a user across more than one page request or visit to a Web site and to store information about that user. The servlet container uses this interface to create a session between an HTTP client and an HTTP server.

Which listener is used to track number of active sessions or users?

Here’s a simple “HttpSessionListener” example to keep track the total number of active sessions in a web application. If you want to keep monitor your session’s create and remove behavior, then consider this listener.

What is HttpSessionListener interface?

public interface HttpSessionListener extends EventListener. Interface for receiving notification events about HttpSession lifecycle changes.

What is session binding in Java?

You can bind objects to sessions to make them available across multiple user interactions. The following table shows the HttpSession methods that provide support for binding objects to the session object.

How is session Tracking carried out?

Session tracking can be done by the server using the HttpSession interface also. The previously stored value can be retrieved by using getAttribute() method. The session object will be available to all of the servlets and JSP’s that the user accesses until the session is closed due to timeout or error.

How does HTTP session object will be created?

How to get the HttpSession object? The HttpServletRequest interface provides two methods to get the object of HttpSession: public HttpSession getSession():Returns the current session associated with this request, or if the request does not have a session, creates one.

What is the use of listener tag in web xml?

This element registers a listener with the Web container. The data provided between the tags is the fully qualified class name for the listener class. The class must implement one or more interfaces from the javax. servlet API, and also have a public constructor that takes no arguments.

Which are session tracking techniques?

There are four techniques used in Session tracking: Cookies. Hidden Form Field. URL Rewriting.

What is HTTP session in Java?

Interface HttpSession. public interface HttpSession. Provides a way to identify a user across more than one page request or visit to a Web site and to store information about that user. The servlet container uses this interface to create a session between an HTTP client and an HTTP server.

How to add sessionlistener class in web XML?

Open Web.xml file from WEB-INF directory of your Project and add following entry for listener tag. sessionListener net.viralpatel.servlet.listener.SessionListener Code language: HTML, XML (xml) In this entry, we have added SessionListener class in Web xml.

What is a session listener?

The Basic Listener The simple listener will keep track of the number of active sessions at all times: The session listener will be triggered when the session is created – sessionCreated: And destroyed – sessionDestroyed:

What is the use of listener class in web XML?

What is the use of listener class in Web XML? Servlet Listener is used for listening to events in a web containers, such as when you create a session, or place an attribute in an session or if you passivate and activate in another container, to subscribe to these events you can configure listener in web. xml , for example HttpSessionListener .

How to create an HTTP session listener using JSP?

The AddUser.jsp will add the user in the session variable. And the DestroySession.jsp will invalidate the session. Create three JSPs and copy following content into it. We are done with the coding part of HTTP Session Listener example. Now execute the project by Run -> Run As -> Run on server (shortcut Alt+Shift+X, R) .