https://javaee.github.io/servlet-spec/: Java.net - The Source for Java Technology Collaboration (GlassFish Community) 
/*
 * 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 HttpSessionBindingListener when it is bound or unbound from a session, or to a HttpSessionAttributeListener that has been configured in the deployment descriptor when any attribute is bound, unbound or replaced in a session. 
The session binds the object by a call to
HttpSession.setAttribute and unbinds the object
by a call to HttpSession.removeAttribute.

Author:Various
See Also:
/**
 *
 * 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 HttpSessionBindingListener. 
Params:
  • session – the session to which the object is bound or unbound
  • name – the name with which the object is bound or unbound
See Also:
/**
     *
     * 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 HttpSessionBindingListener. 
Params:
  • session – the session to which the object is bound or unbound
  • name – the name with which the object is bound or unbound
  • value – the object that is bound or unbound
See Also:
/**
     *
     * 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. 
/** 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.

Returns:a string specifying the name with which
        the object is bound to or unbound from the session
/**
     * 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.

Returns:the value of the attribute that has been added, removed
or replaced
Since:Servlet 2.3
/**
     * 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;   
    }
}