001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.activemq.transport.discovery;
018    
019    import org.apache.activemq.command.DiscoveryEvent;
020    
021    /**
022     * A listener of services being added or removed from a network
023     * 
024     * 
025     */
026    public interface DiscoveryListener {
027        public static final String DISCOVERED_OPTION_PREFIX = "discovered.";
028    
029        void onServiceAdd(DiscoveryEvent event);
030    
031        void onServiceRemove(DiscoveryEvent event);
032    
033    }