Java tutorial
/* * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved. * Copyright 2004 The Apache Software Foundation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package javax.servlet.http; /** * * Events of this type are either sent to an object that implements * {@link HttpSessionBindingListener} when it is bound or unbound from a * session, or to a {@link HttpSessionAttributeListener} that has been * configured in the deployment descriptor when any attribute is bound, unbound * or replaced in a session. * * <p>The session binds the object by a call to * <code>HttpSession.setAttribute</code> and unbinds the object * by a call to <code>HttpSession.removeAttribute</code>. * * @author Various * * @see HttpSession * @see HttpSessionBindingListener * @see HttpSessionAttributeListener */ public class HttpSessionBindingEvent extends HttpSessionEvent { private static final long serialVersionUID = 7308000419984825907L; /* The name to which the object is being bound or unbound */ private String name; /* The object is being bound or unbound */ private Object value; /** * * Constructs an event that notifies an object that it * has been bound to or unbound from a session. * To receive the event, the object must implement * {@link HttpSessionBindingListener}. * * @param session the session to which the object is bound or unbound * @param name the name with which the object is bound or unbound * * @see #getName * @see #getSession */ public HttpSessionBindingEvent(HttpSession session, String name) { super(session); this.name = name; } /** * * Constructs an event that notifies an object that it * has been bound to or unbound from a session. * To receive the event, the object must implement * {@link HttpSessionBindingListener}. * * @param session the session to which the object is bound or unbound * @param name the name with which the object is bound or unbound * @param value the object that is bound or unbound * * @see #getName * @see #getSession */ public HttpSessionBindingEvent(HttpSession session, String name, Object value) { super(session); this.name = name; this.value = value; } /** Return the session that changed. */ @Override public HttpSession getSession() { return super.getSession(); } /** * Returns the name with which the attribute is bound to or * unbound from the session. * * @return a string specifying the name with which * the object is bound to or unbound from the session */ public String getName() { return name; } /** * Returns the value of the attribute that has been added, removed or * replaced. If the attribute was added (or bound), this is the value of the * attribute. If the attribute was removed (or unbound), this is the value * of the removed attribute. If the attribute was replaced, this is the old * value of the attribute. * * @return the value of the attribute that has been added, removed * or replaced * * @since Servlet 2.3 */ public Object getValue() { return this.value; } }