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 java.io.IOException; 020 import java.net.URI; 021 import java.util.concurrent.ConcurrentHashMap; 022 023 import org.apache.activemq.util.FactoryFinder; 024 import org.apache.activemq.util.IOExceptionSupport; 025 026 public abstract class DiscoveryAgentFactory { 027 028 private static final FactoryFinder DISCOVERY_AGENT_FINDER = new FactoryFinder("META-INF/services/org/apache/activemq/transport/discoveryagent/"); 029 private static final ConcurrentHashMap<String, DiscoveryAgentFactory> DISCOVERY_AGENT_FACTORYS = new ConcurrentHashMap<String, DiscoveryAgentFactory>(); 030 031 /** 032 * @param uri 033 * @return 034 * @throws IOException 035 */ 036 private static DiscoveryAgentFactory findDiscoveryAgentFactory(URI uri) throws IOException { 037 String scheme = uri.getScheme(); 038 if (scheme == null) { 039 throw new IOException("DiscoveryAgent scheme not specified: [" + uri + "]"); 040 } 041 DiscoveryAgentFactory daf = DISCOVERY_AGENT_FACTORYS.get(scheme); 042 if (daf == null) { 043 // Try to load if from a META-INF property. 044 try { 045 daf = (DiscoveryAgentFactory)DISCOVERY_AGENT_FINDER.newInstance(scheme); 046 DISCOVERY_AGENT_FACTORYS.put(scheme, daf); 047 } catch (Throwable e) { 048 throw IOExceptionSupport.create("DiscoveryAgent scheme NOT recognized: [" + scheme + "]", e); 049 } 050 } 051 return daf; 052 } 053 054 public static DiscoveryAgent createDiscoveryAgent(URI uri) throws IOException { 055 DiscoveryAgentFactory tf = findDiscoveryAgentFactory(uri); 056 return tf.doCreateDiscoveryAgent(uri); 057 058 } 059 060 protected abstract DiscoveryAgent doCreateDiscoveryAgent(URI uri) throws IOException; 061 // { 062 // try { 063 // String type = ( uri.getScheme() == null ) ? uri.getPath() : 064 // uri.getScheme(); 065 // DiscoveryAgent rc = (DiscoveryAgent) 066 // discoveryAgentFinder.newInstance(type); 067 // Map options = URISupport.parseParamters(uri); 068 // IntrospectionSupport.setProperties(rc, options); 069 // if( rc.getClass() == SimpleDiscoveryAgent.class ) { 070 // CompositeData data = URISupport.parseComposite(uri); 071 // ((SimpleDiscoveryAgent)rc).setServices(data.getComponents()); 072 // } 073 // return rc; 074 // } catch (Throwable e) { 075 // throw IOExceptionSupport.create("Could not create discovery agent: "+uri, 076 // e); 077 // } 078 // } 079 }