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.impl;
018    
019    import java.util.List;
020    
021    import org.apache.camel.Consumer;
022    import org.apache.camel.Endpoint;
023    import org.apache.camel.Navigate;
024    import org.apache.camel.Processor;
025    import org.apache.camel.Service;
026    import org.apache.camel.SuspendableService;
027    import org.apache.camel.processor.DelegateAsyncProcessor;
028    import org.apache.camel.spi.RouteContext;
029    
030    /**
031     * A {@link DefaultRoute} which starts with an
032     * <a href="http://camel.apache.org/event-driven-consumer.html">Event Driven Consumer</a>
033     * <p/>
034     * Use the API from {@link org.apache.camel.CamelContext} to control the lifecycle of a route,
035     * such as starting and stopping using the {@link org.apache.camel.CamelContext#startRoute(String)}
036     * and {@link org.apache.camel.CamelContext#stopRoute(String)} methods.
037     *
038     * @version 
039     */
040    public class EventDrivenConsumerRoute extends DefaultRoute {
041        private final Processor processor;
042        private Consumer consumer;
043    
044        public EventDrivenConsumerRoute(RouteContext routeContext, Endpoint endpoint, Processor processor) {
045            super(routeContext, endpoint);
046            this.processor = processor;
047        }
048    
049        @Override
050        public String toString() {
051            return "EventDrivenConsumerRoute[" + getEndpoint() + " -> " + processor + "]";
052        }
053    
054        public Processor getProcessor() {
055            return processor;
056        }
057    
058        /**
059         * Factory method to lazily create the complete list of services required for this route
060         * such as adding the processor or consumer
061         */
062        @Override
063        protected void addServices(List<Service> services) throws Exception {
064            Endpoint endpoint = getEndpoint();
065            consumer = endpoint.createConsumer(processor);
066            if (consumer != null) {
067                services.add(consumer);
068            }
069            Processor processor = getProcessor();
070            if (processor instanceof Service) {
071                services.add((Service)processor);
072            }
073        }
074    
075        @SuppressWarnings("unchecked")
076        public Navigate<Processor> navigate() {
077            Processor answer = getProcessor();
078    
079            // we do not want to navigate the instrument and inflight processors
080            // which is the first 2 delegate async processors, so skip them
081            // skip the instrumentation processor if this route was wrapped by one
082            if (answer instanceof DelegateAsyncProcessor) {
083                answer = ((DelegateAsyncProcessor) answer).getProcessor();
084                if (answer instanceof DelegateAsyncProcessor) {
085                    answer = ((DelegateAsyncProcessor) answer).getProcessor();
086                }
087            }
088    
089            if (answer instanceof Navigate) {
090                return (Navigate<Processor>) answer;
091            }
092            return null;
093        }
094    
095        public Consumer getConsumer() {
096            return consumer;
097        }
098    
099        public boolean supportsSuspension() {
100            return consumer instanceof SuspendableService;
101        }
102    }