    001/*
    002 * Copyright 2001-2004 The Apache Software Foundation.
    003 *
    004 * Licensed under the Apache License, Version 2.0 (the "License");
    005 * you may not use this file except in compliance with the License.
    006 * You may obtain a copy of the License at
    007 *
    008 *      http://www.apache.org/licenses/LICENSE-2.0
    009 *
    010 * Unless required by applicable law or agreed to in writing, software
    011 * distributed under the License is distributed on an "AS IS" BASIS,
    012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    013 * See the License for the specific language governing permissions and
    014 * limitations under the License.
    015 */
    016
    017package org.apache.log4j.spi;
    018
    019import org.apache.log4j.*;
    020
    021/**
    022   Listen to events occurring within a {@link
    023   org.apache.log4j.Hierarchy Hierarchy}.
    024
    025   @author Ceki G&uuml;lc&uuml;
    026   @since 1.2
    027
    028 */
    029public interface HierarchyEventListener {
    030
    031    // public
    032    // void categoryCreationEvent(Category cat);
    033
    034    public void addAppenderEvent(Category cat, Appender appender);
    035
    036    public void removeAppenderEvent(Category cat, Appender appender);
    037
    038}