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.camel.component.event;
018
019import java.util.LinkedHashSet;
020import java.util.Map;
021import java.util.Set;
022
023import org.apache.camel.impl.DefaultComponent;
024import org.slf4j.Logger;
025import org.slf4j.LoggerFactory;
026import org.springframework.beans.BeansException;
027import org.springframework.context.ApplicationContext;
028import org.springframework.context.ApplicationContextAware;
029import org.springframework.context.ApplicationEvent;
030import org.springframework.context.ConfigurableApplicationContext;
031
032/**
033 * An <a href="http://camel.apache.org/event.html">Event Component</a>
034 * for working with Spring ApplicationEvents
035 * 
036 * @version 
037 */
038public class EventComponent extends DefaultComponent implements ApplicationContextAware {
039    private static final Logger LOG = LoggerFactory.getLogger(EventComponent.class);
040    private ApplicationContext applicationContext;
041    private final Set<EventEndpoint> endpoints = new LinkedHashSet<EventEndpoint>();
042
043    public EventComponent() {
044    }
045
046    public EventComponent(ApplicationContext applicationContext) {
047        setApplicationContext(applicationContext);
048    }
049
050    public ApplicationContext getApplicationContext() {
051        return applicationContext;
052    }
053
054    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
055        this.applicationContext = applicationContext;
056    }
057
058    public ConfigurableApplicationContext getConfigurableApplicationContext() {
059        ApplicationContext applicationContext = getApplicationContext();
060        if (applicationContext instanceof ConfigurableApplicationContext) {
061            return (ConfigurableApplicationContext)applicationContext;
062        } else {
063            throw new IllegalArgumentException("Class: " + applicationContext.getClass().getName() + " is not an instanceof ConfigurableApplicationContext.");
064        }
065    }
066
067    protected EventEndpoint createEndpoint(String uri, String remaining, Map<String, Object> parameters) throws Exception {
068        EventEndpoint answer = new EventEndpoint(uri, this);
069        setProperties(answer, parameters);
070        return answer;
071    }
072
073    protected void consumerStarted(EventEndpoint endpoint) {
074        endpoints.add(endpoint);
075    }
076
077    protected void consumerStopped(EventEndpoint endpoint) {
078        endpoints.remove(endpoint);
079    }
080
081    public void onApplicationEvent(ApplicationEvent event) {
082        // broadcast to the endpoints in use
083        for (EventEndpoint endpoint : endpoints) {
084            try {
085                endpoint.onApplicationEvent(event);
086            } catch (Exception e) {
087                LOG.warn("Error on application event " + event + ". This exception will be ignored.", e);
088            }
089        }
090    }
091
092    @Override
093    protected void doStop() throws Exception {
094        endpoints.clear();
095        super.doStop();
096    }
097}