001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019 020 package javax.servlet.http; 021 022 import java.util.EventListener; 023 024 /** 025 * Causes an object to be notified when it is bound to 026 * or unbound from a session. The object is notified 027 * by an {@link HttpSessionBindingEvent} object. This may be as a result 028 * of a servlet programmer explicitly unbinding an attribute from a session, 029 * due to a session being invalidated, or due to a session timing out. 030 * 031 * 032 * @author Various 033 * @version $Version$ 034 * 035 * @see HttpSession 036 * @see HttpSessionBindingEvent 037 */ 038 public interface HttpSessionBindingListener extends EventListener { 039 /** 040 * 041 * Notifies the object that it is being bound to 042 * a session and identifies the session. 043 * 044 * @param event the event that identifies the 045 * session 046 * 047 * @see #valueUnbound 048 * 049 */ 050 051 public void valueBound(HttpSessionBindingEvent event); 052 053 054 055 /** 056 * 057 * Notifies the object that it is being unbound 058 * from a session and identifies the session. 059 * 060 * @param event the event that identifies 061 * the session 062 * 063 * @see #valueBound 064 * 065 */ 066 067 public void valueUnbound(HttpSessionBindingEvent event); 068 069 070 } 071