/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.log4j.spi;

import org.apache.logging.log4j.core.Appender;
import org.apache.logging.log4j.Logger;

/**
   Listen to events occurring within a Hierarchy.

   @author Ceki G&uuml;lc&uuml;
   @since 1.2
   
 */
public interface HierarchyEventListener {

  void addAppenderEvent(Logger logger, Appender appender);

  void removeAppenderEvent(Logger logger, Appender appender);

}