1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 20 package javax.servlet; 21 22 import java.util.EventListener; 23 24 /** 25 * A ServletRequestAttributeListener can be implemented by the 26 * developer interested in being notified of request attribute 27 * changes. Notifications will be generated while the request 28 * is within the scope of the web application in which the listener 29 * is registered. A request is defined as coming into scope when 30 * it is about to enter the first servlet or filter in each web 31 * application, as going out of scope when it exits the last servlet 32 * or the first filter in the chain. 33 * 34 * @since Servlet 2.4 35 */ 36 37 public interface ServletRequestAttributeListener extends EventListener { 38 /** Notification that a new attribute was added to the 39 ** servlet request. Called after the attribute is added. 40 */ 41 public void attributeAdded(ServletRequestAttributeEvent srae); 42 43 /** Notification that an existing attribute has been removed from the 44 ** servlet request. Called after the attribute is removed. 45 */ 46 public void attributeRemoved(ServletRequestAttributeEvent srae); 47 48 /** Notification that an attribute was replaced on the 49 ** servlet request. Called after the attribute is replaced. 50 */ 51 public void attributeReplaced(ServletRequestAttributeEvent srae); 52 } 53