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.masterslave;
018    
019    import java.net.URI;
020    import org.apache.activemq.transport.discovery.simple.SimpleDiscoveryAgent;
021    import org.slf4j.Logger;
022    import org.slf4j.LoggerFactory;
023    
024    /**
025     * A static DiscoveryAgent that supports connecting to a Master / Slave tuple
026     * of brokers.
027     */
028    public class MasterSlaveDiscoveryAgent extends SimpleDiscoveryAgent {
029    
030        private final static Logger LOG = LoggerFactory.getLogger(MasterSlaveDiscoveryAgent.class);
031    
032        private String[] msServices = new String[]{};
033    
034        @Override
035        public String[] getServices() {
036            return msServices;
037        }
038    
039        @Override
040        public void setServices(String services) {
041            this.msServices = services.split(",");
042            configureServices();
043        }
044    
045        @Override
046        public void setServices(String services[]) {
047            this.msServices = services;
048            configureServices();
049        }
050    
051        @Override
052        public void setServices(URI services[]) {
053            this.msServices = new String[services.length];
054            for (int i = 0; i < services.length; i++) {
055                this.msServices[i] = services[i].toString();
056            }
057            configureServices();
058        }
059    
060        protected void configureServices() {
061            if ((msServices == null) || (msServices.length < 2)) {
062                LOG.error("masterSlave requires at least 2 URIs");
063                msServices = new String[]{};
064                throw new IllegalArgumentException("Expecting at least 2 arguments");
065            }
066    
067            StringBuffer buf = new StringBuffer();
068    
069            buf.append("failover:(");
070    
071            for (int i = 0; i < (msServices.length - 1); i++) {
072                buf.append(msServices[i]);
073                buf.append(',');
074            }
075            buf.append(msServices[msServices.length - 1]);
076    
077            buf.append(")?randomize=false&maxReconnectAttempts=0");
078    
079            super.setServices(new String[]{buf.toString()});
080        }
081    
082    }