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.component.browse;
018    
019    import java.beans.PropertyChangeListener;
020    import java.beans.PropertyChangeSupport;
021    import java.util.List;
022    import java.util.concurrent.CopyOnWriteArrayList;
023    
024    import org.apache.camel.CamelContext;
025    import org.apache.camel.Component;
026    import org.apache.camel.Consumer;
027    import org.apache.camel.Exchange;
028    import org.apache.camel.Processor;
029    import org.apache.camel.Producer;
030    import org.apache.camel.Service;
031    import org.apache.camel.impl.DefaultEndpoint;
032    import org.apache.camel.impl.DefaultProducer;
033    import org.apache.camel.processor.loadbalancer.LoadBalancerConsumer;
034    import org.apache.camel.processor.loadbalancer.TopicLoadBalancer;
035    import org.apache.camel.spi.BrowsableEndpoint;
036    
037    /**
038     * An endpoint which maintains a {@link List} of {@link Exchange} instances
039     * which can be useful for tooling, debugging and visualising routes.
040     *
041     * @version $Revision: 736555 $
042     */
043    public class BrowseEndpoint extends DefaultEndpoint implements BrowsableEndpoint, Service {
044        private List<Exchange> exchanges;
045        private TopicLoadBalancer loadBalancer = new TopicLoadBalancer();
046        // TODO: firing of property changes not implemented
047        private PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);
048    
049        public BrowseEndpoint(String uri, CamelContext camelContext) {
050            super(uri, camelContext);
051        }
052    
053        public BrowseEndpoint(String uri, Component component) {
054            super(uri, component);
055        }
056    
057        public BrowseEndpoint(String endpointUri) {
058            super(endpointUri);
059        }
060    
061        public boolean isSingleton() {
062            return true;
063        }
064    
065        public List<Exchange> getExchanges() {
066            return exchanges;
067        }
068    
069        public TopicLoadBalancer getLoadBalancer() {
070            return loadBalancer;
071        }
072    
073        public void addPropertyChangeListener(PropertyChangeListener listener) {
074            propertyChangeSupport.addPropertyChangeListener(listener);
075        }
076    
077        public void removePropertyChangeListener(PropertyChangeListener listener) {
078            propertyChangeSupport.removePropertyChangeListener(listener);
079        }
080    
081        public Producer createProducer() throws Exception {
082            return new DefaultProducer(this) {
083                public void process(Exchange exchange) throws Exception {
084                    onExchange(exchange);
085                }
086            };
087        }
088    
089        public Consumer createConsumer(Processor processor) throws Exception {
090            return new LoadBalancerConsumer(this, processor, loadBalancer);
091        }
092    
093        protected List<Exchange> createExchangeList() {
094            return new CopyOnWriteArrayList<Exchange>();
095        }
096    
097        /**
098         * Invoked on a message exchange being sent by a producer
099         *
100         * @param exchange the exchange
101         * @throws Exception is thrown if failed to process the exchange
102         */
103        protected void onExchange(Exchange exchange) throws Exception {
104            exchanges.add(exchange);
105    
106            // lets fire any consumers
107            loadBalancer.process(exchange);
108        }
109    
110        public void start() throws Exception {
111            exchanges = createExchangeList();
112        }
113    
114        public void stop() throws Exception {
115            if (exchanges != null) {
116                exchanges.clear();
117                exchanges = null;
118            }
119        }
120    }