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.camel.processor;
018    
019    import java.util.concurrent.Callable;
020    import java.util.concurrent.ExecutorService;
021    import java.util.concurrent.ScheduledThreadPoolExecutor;
022    import java.util.concurrent.ThreadFactory;
023    
024    import org.apache.camel.AsyncCallback;
025    import org.apache.camel.Endpoint;
026    import org.apache.camel.Exchange;
027    import org.apache.camel.ExchangePattern;
028    
029    /**
030     * Processor for wire tapping exchanges to an endpoint destination.
031     *
032     * @version $Revision: 751648 $
033     */
034    public class WireTapProcessor extends SendProcessor {
035    
036        private int defaultThreadPoolSize = 5;
037        private ExecutorService executorService;
038    
039        public WireTapProcessor(Endpoint destination) {
040            super(destination);
041        }
042    
043        public WireTapProcessor(Endpoint destination, ExchangePattern pattern) {
044            super(destination, pattern);
045        }
046    
047        @Override
048        protected void doStart() throws Exception {
049            super.doStart();
050        }
051    
052        @Override
053        protected void doStop() throws Exception {
054            if (executorService != null) {
055                executorService.shutdown();
056            }
057            super.doStop();
058        }
059    
060        @Override
061        public String toString() {
062            return "wireTap(" + destination.getEndpointUri() + ")";
063        }
064    
065        public void process(Exchange exchange) throws Exception {
066            if (producer == null) {
067                if (isStopped()) {
068                    LOG.warn("Ignoring exchange sent after processor is stopped: " + exchange);
069                } else {
070                    throw new IllegalStateException("No producer, this processor has not been started!");
071                }
072            } else {
073                final Exchange wireTapExchange = configureExchange(exchange);
074    
075                // use submit instead of execute to force it to use a new thread, execute might
076                // decide to use current thread, so we must submit a new task
077                // as we dont care for the response we dont hold the future object and wait for the result
078                getExecutorService().submit(new Callable<Object>() {
079                    public Object call() throws Exception {
080                        if (LOG.isDebugEnabled()) {
081                            LOG.debug("Processing wiretap: " + wireTapExchange);
082                        }
083                        producer.process(wireTapExchange);
084                        return null;
085                    }
086                });
087            }
088        }
089    
090        public boolean process(Exchange exchange, final AsyncCallback callback) {
091            if (producer == null) {
092                if (isStopped()) {
093                    LOG.warn("Ignoring exchange sent after processor is stopped: " + exchange);
094                } else {
095                    exchange.setException(new IllegalStateException("No producer, this processor has not been started!"));
096                }
097                callback.done(true);
098                return true;
099            } else {
100                exchange = configureExchange(exchange);
101    
102                final Exchange wireTapExchange = configureExchange(exchange);
103    
104                // use submit instead of execute to force it to use a new thread, execute might
105                // decide to use current thread, so we must submit a new task
106                // as we dont care for the response we dont hold the future object and wait for the result
107                getExecutorService().submit(new Callable<Object>() {
108                    public Object call() throws Exception {
109                        if (LOG.isDebugEnabled()) {
110                            LOG.debug("Processing wiretap: " + wireTapExchange);
111                        }
112                        return processor.process(wireTapExchange, callback);
113                    }
114                });
115    
116                // return true to indicate caller its okay, and he should not wait as this wiretap
117                // is a fire and forget
118                return true;
119            }
120        }
121    
122    
123        @Override
124        protected Exchange configureExchange(Exchange exchange) {
125            // must use a copy as we dont want it to cause side effects of the original exchange
126            Exchange copy = exchange.copy();
127            // set MEP to InOnly as this wire tap is a fire and forget
128            copy.setPattern(ExchangePattern.InOnly);
129            return copy;
130        }
131    
132        public ExecutorService getExecutorService() {
133            if (executorService == null) {
134                executorService = createExecutorService();
135            }
136            return executorService;
137        }
138    
139        private ExecutorService createExecutorService() {
140            return new ScheduledThreadPoolExecutor(defaultThreadPoolSize, new ThreadFactory() {
141                int counter;
142    
143                public synchronized Thread newThread(Runnable runnable) {
144                    Thread thread = new Thread(runnable);
145                    thread.setName("Thread: " + (++counter) + " " + WireTapProcessor.this.toString());
146                    return thread;
147                }
148            });
149        }
150    
151        public void setExecutorService(ExecutorService executorService) {
152            this.executorService = executorService;
153        }
154        
155    }