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 */ 017package org.apache.activemq.transport.discovery; 018 019import java.io.IOException; 020import java.net.URI; 021import java.util.concurrent.ConcurrentHashMap; 022import java.util.concurrent.ConcurrentMap; 023 024import org.apache.activemq.util.FactoryFinder; 025import org.apache.activemq.util.IOExceptionSupport; 026 027public abstract class DiscoveryAgentFactory { 028 029 private static final FactoryFinder DISCOVERY_AGENT_FINDER = new FactoryFinder("META-INF/services/org/apache/activemq/transport/discoveryagent/"); 030 private static final ConcurrentMap<String, DiscoveryAgentFactory> DISCOVERY_AGENT_FACTORYS = new ConcurrentHashMap<String, DiscoveryAgentFactory>(); 031 032 /** 033 * @param uri 034 * @return 035 * @throws IOException 036 */ 037 private static DiscoveryAgentFactory findDiscoveryAgentFactory(URI uri) throws IOException { 038 String scheme = uri.getScheme(); 039 if (scheme == null) { 040 throw new IOException("DiscoveryAgent scheme not specified: [" + uri + "]"); 041 } 042 DiscoveryAgentFactory daf = DISCOVERY_AGENT_FACTORYS.get(scheme); 043 if (daf == null) { 044 // Try to load if from a META-INF property. 045 try { 046 daf = (DiscoveryAgentFactory)DISCOVERY_AGENT_FINDER.newInstance(scheme); 047 DISCOVERY_AGENT_FACTORYS.put(scheme, daf); 048 } catch (Throwable e) { 049 throw IOExceptionSupport.create("DiscoveryAgent scheme NOT recognized: [" + scheme + "]", e); 050 } 051 } 052 return daf; 053 } 054 055 public static DiscoveryAgent createDiscoveryAgent(URI uri) throws IOException { 056 DiscoveryAgentFactory tf = findDiscoveryAgentFactory(uri); 057 return tf.doCreateDiscoveryAgent(uri); 058 059 } 060 061 protected abstract DiscoveryAgent doCreateDiscoveryAgent(URI uri) throws IOException; 062 // { 063 // try { 064 // String type = ( uri.getScheme() == null ) ? uri.getPath() : 065 // uri.getScheme(); 066 // DiscoveryAgent rc = (DiscoveryAgent) 067 // discoveryAgentFinder.newInstance(type); 068 // Map options = URISupport.parseParamters(uri); 069 // IntrospectionSupport.setProperties(rc, options); 070 // if( rc.getClass() == SimpleDiscoveryAgent.class ) { 071 // CompositeData data = URISupport.parseComposite(uri); 072 // ((SimpleDiscoveryAgent)rc).setServices(data.getComponents()); 073 // } 074 // return rc; 075 // } catch (Throwable e) { 076 // throw IOExceptionSupport.create("Could not create discovery agent: "+uri, 077 // e); 078 // } 079 // } 080}