import javax.servlet.http.*;

public class MySessionAttribute
   implements HttpSessionBindingListener,
   HttpSessionActivationListener
   {
  public MySessionAttribute() {
    System.out.println("********** MySessionAttribute() created by container");
  } // required to register listeners
 
  String scope;
  MySessionAttribute(String scope) {
    this.scope = scope;
    System.out.println("*** MySessionAttribute: object created" + scope);
  }
 
  // Attribute can find out when it is bound or unbound
  // HttpSessionBindingListener
  public void valueBound(HttpSessionBindingEvent hsbe)  {
    System.out.println("*** HttpSessionBindingListener.valueBound() scope=" + scope);
  }

  public void valueUnbound(HttpSessionBindingEvent hsbe)  { }
  // HttpSessionBindingListener
 
  // when sesion migrates to another JVM
  // HttpSessionActivationListener
  public void sessionWillPassivate(HttpSessionEvent hse) {
    HttpSession session = hse.getSession();
    System.out.println("HttpSessionActivationListener.passivate:" + session.getId());
  }

  public void sessionDidActivate(HttpSessionEvent hse) {
    HttpSession session = hse.getSession();
    System.out.println("HttpSessionActivationListener.activated:" + session.getId());
  }
  // end HttpSessionActivationListener
}