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.udp;
018    
019    import java.io.IOException;
020    import java.net.URI;
021    import java.net.URISyntaxException;
022    import java.net.UnknownHostException;
023    import java.util.HashMap;
024    import java.util.Map;
025    
026    import org.apache.activemq.openwire.OpenWireFormat;
027    import org.apache.activemq.transport.CommandJoiner;
028    import org.apache.activemq.transport.InactivityMonitor;
029    import org.apache.activemq.transport.Transport;
030    import org.apache.activemq.transport.TransportFactory;
031    import org.apache.activemq.transport.TransportLoggerFactory;
032    import org.apache.activemq.transport.TransportServer;
033    import org.apache.activemq.transport.reliable.DefaultReplayStrategy;
034    import org.apache.activemq.transport.reliable.ExceptionIfDroppedReplayStrategy;
035    import org.apache.activemq.transport.reliable.ReliableTransport;
036    import org.apache.activemq.transport.reliable.ReplayStrategy;
037    import org.apache.activemq.transport.reliable.Replayer;
038    import org.apache.activemq.transport.tcp.TcpTransportFactory;
039    import org.apache.activemq.util.IOExceptionSupport;
040    import org.apache.activemq.util.IntrospectionSupport;
041    import org.apache.activemq.util.URISupport;
042    import org.apache.activemq.wireformat.WireFormat;
043    import org.apache.commons.logging.Log;
044    import org.apache.commons.logging.LogFactory;
045    
046    /**
047     * @author David Martin Clavo david(dot)martin(dot)clavo(at)gmail.com (logging improvement modifications)
048     * @version $Revision: 777806 $
049     */
050    public class UdpTransportFactory extends TransportFactory {
051        
052        private static final Log log = LogFactory.getLog(TcpTransportFactory.class);
053        
054        public TransportServer doBind(final URI location) throws IOException {
055            try {
056                Map<String, String> options = new HashMap<String, String>(URISupport.parseParamters(location));
057                if (options.containsKey("port")) {
058                    throw new IllegalArgumentException("The port property cannot be specified on a UDP server transport - please use the port in the URI syntax");
059                }
060                WireFormat wf = createWireFormat(options);
061                int port = location.getPort();
062                OpenWireFormat openWireFormat = asOpenWireFormat(wf);
063                UdpTransport transport = (UdpTransport) createTransport(location, wf);
064    
065                Transport configuredTransport = configure(transport, wf, options, true);
066                UdpTransportServer server = new UdpTransportServer(location, transport, configuredTransport, createReplayStrategy());
067                return server;
068            } catch (URISyntaxException e) {
069                throw IOExceptionSupport.create(e);
070            } catch (Exception e) {
071                throw IOExceptionSupport.create(e);
072            }
073        }
074    
075        public Transport configure(Transport transport, WireFormat format, Map options) throws Exception {
076            return configure(transport, format, options, false);
077        }
078    
079        public Transport compositeConfigure(Transport transport, WireFormat format, Map options) {
080            IntrospectionSupport.setProperties(transport, options);
081            final UdpTransport udpTransport = (UdpTransport)transport;
082    
083            // deal with fragmentation
084            transport = new CommandJoiner(transport, asOpenWireFormat(format));
085    
086            if (udpTransport.isTrace()) {
087                try {
088                    transport = TransportLoggerFactory.getInstance().createTransportLogger(transport);
089                } catch (Throwable e) {
090                    log.error("Could not create TransportLogger object for: " + TransportLoggerFactory.defaultLogWriterName + ", reason: " + e, e);
091                }
092            }
093    
094            transport = new InactivityMonitor(transport, format);
095    
096            if (format instanceof OpenWireFormat) {
097                transport = configureClientSideNegotiator(transport, format, udpTransport);
098            }
099    
100            return transport;
101        }
102    
103        protected Transport createTransport(URI location, WireFormat wf) throws UnknownHostException, IOException {
104            OpenWireFormat wireFormat = asOpenWireFormat(wf);
105            return new UdpTransport(wireFormat, location);
106        }
107    
108        /**
109         * Configures the transport
110         * 
111         * @param acceptServer true if this transport is used purely as an 'accept'
112         *                transport for new connections which work like TCP
113         *                SocketServers where new connections spin up a new separate
114         *                UDP transport
115         */
116        protected Transport configure(Transport transport, WireFormat format, Map options, boolean acceptServer) throws Exception {
117            IntrospectionSupport.setProperties(transport, options);
118            UdpTransport udpTransport = (UdpTransport)transport;
119    
120            OpenWireFormat openWireFormat = asOpenWireFormat(format);
121    
122            if (udpTransport.isTrace()) {
123                transport = TransportLoggerFactory.getInstance().createTransportLogger(transport);
124            }
125    
126            transport = new InactivityMonitor(transport, format);
127    
128            if (!acceptServer && format instanceof OpenWireFormat) {
129                transport = configureClientSideNegotiator(transport, format, udpTransport);
130            }
131    
132            // deal with fragmentation
133    
134            if (acceptServer) {
135                // lets not support a buffer of messages to enable reliable
136                // messaging on the 'accept server' transport
137                udpTransport.setReplayEnabled(false);
138    
139                // we don't want to do reliable checks on this transport as we
140                // delegate to one that does
141                transport = new CommandJoiner(transport, openWireFormat);
142                return transport;
143            } else {
144                ReliableTransport reliableTransport = new ReliableTransport(transport, udpTransport);
145                Replayer replayer = reliableTransport.getReplayer();
146                reliableTransport.setReplayStrategy(createReplayStrategy(replayer));
147    
148                // Joiner must be on outside as the inbound messages must be
149                // processed by the reliable transport first
150                return new CommandJoiner(reliableTransport, openWireFormat);
151            }
152        }
153    
154        protected ReplayStrategy createReplayStrategy(Replayer replayer) {
155            if (replayer != null) {
156                return new DefaultReplayStrategy(5);
157            }
158            return new ExceptionIfDroppedReplayStrategy(1);
159        }
160    
161        protected ReplayStrategy createReplayStrategy() {
162            return new DefaultReplayStrategy(5);
163        }
164    
165        protected Transport configureClientSideNegotiator(Transport transport, WireFormat format, final UdpTransport udpTransport) {
166            return new ResponseRedirectInterceptor(transport, udpTransport);
167        }
168    
169        protected OpenWireFormat asOpenWireFormat(WireFormat wf) {
170            OpenWireFormat answer = (OpenWireFormat)wf;
171            return answer;
172        }
173    }