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package javax.servlet.http;

import java.util.EventListener;


Interface for receiving notification events about HttpSession
id changes.

In order to receive these notification events, the implementation class must be either declared in the deployment descriptor of the web application, annotated with WebListener, or registered via one of the addListener methods defined on ServletContext. 
The order in which implementations of this interface are invoked is
unspecified.

Since:Servlet 3.1
/**
 * Interface for receiving notification events about HttpSession
 * id changes.
 *
 * <p>In order to receive these notification events, the implementation
 * class must be either declared in the deployment descriptor of the web
 * application, annotated with {@link javax.servlet.annotation.WebListener},
 * or registered via one of the addListener methods defined on
 * {@link javax.servlet.ServletContext}.
 *
 * <p>The order in which implementations of this interface are invoked is
 * unspecified.
 *
 * @since Servlet 3.1
 */

public interface HttpSessionIdListener extends EventListener {

    
Receives notification that session id has been changed in a
session.

Params:
  • event – the HttpSessionBindingEvent containing the session
and the name and (old) value of the attribute that was replaced
  • oldSessionId – the old session id
/**
     * Receives notification that session id has been changed in a
     * session.
     *
     * @param event the HttpSessionBindingEvent containing the session
     * and the name and (old) value of the attribute that was replaced
     *
     * @param oldSessionId the old session id
     */
    public void sessionIdChanged(HttpSessionEvent event, String oldSessionId);

}