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.management;
018
019import java.util.EventObject;
020
021import org.apache.camel.CamelContext;
022import org.apache.camel.CamelContextAware;
023import org.apache.camel.Endpoint;
024import org.apache.camel.Exchange;
025import org.apache.camel.Producer;
026import org.apache.camel.support.EventNotifierSupport;
027import org.apache.camel.util.ObjectHelper;
028import org.apache.camel.util.ServiceHelper;
029import org.apache.camel.util.URISupport;
030
031/**
032 * A {@link org.apache.camel.spi.EventNotifier} which publishes the {@link EventObject} to some
033 * {@link org.apache.camel.Endpoint}.
034 * <p/>
035 * This notifier is only enabled when {@link CamelContext} is started. This avoids problems when
036 * sending notifications during start/shutdown of {@link CamelContext} which causes problems by
037 * sending those events to Camel routes by this notifier.
038 *
039 * @version 
040 */
041public class PublishEventNotifier extends EventNotifierSupport implements CamelContextAware {
042
043    private CamelContext camelContext;
044    private Endpoint endpoint;
045    private String endpointUri;
046    private Producer producer;
047
048    public void notify(EventObject event) throws Exception {
049        // only notify when we are started
050        if (!isStarted()) {
051            log.debug("Cannot publish event as notifier is not started: {}", event);
052            return;
053        }
054
055        // only notify when camel context is running
056        if (!camelContext.getStatus().isStarted()) {
057            log.debug("Cannot publish event as CamelContext is not started: {}", event);
058            return;
059        }
060
061        Exchange exchange = producer.createExchange();
062        exchange.getIn().setBody(event);
063
064        // make sure we don't send out events for this as well
065        // mark exchange as being published to event, to prevent creating new events
066        // for this as well (causing a endless flood of events)
067        exchange.setProperty(Exchange.NOTIFY_EVENT, Boolean.TRUE);
068        try {
069            producer.process(exchange);
070        } finally {
071            // and remove it when its done
072            exchange.removeProperty(Exchange.NOTIFY_EVENT);
073        }
074    }
075
076    public boolean isEnabled(EventObject event) {
077        return true;
078    }
079
080    public CamelContext getCamelContext() {
081        return camelContext;
082    }
083
084    public void setCamelContext(CamelContext camelContext) {
085        this.camelContext = camelContext;
086    }
087
088    public Endpoint getEndpoint() {
089        return endpoint;
090    }
091
092    public void setEndpoint(Endpoint endpoint) {
093        this.endpoint = endpoint;
094    }
095
096    public String getEndpointUri() {
097        return endpointUri;
098    }
099
100    public void setEndpointUri(String endpointUri) {
101        this.endpointUri = endpointUri;
102    }
103
104    @Override
105    protected void doStart() throws Exception {
106        ObjectHelper.notNull(camelContext, "camelContext", this);
107        if (endpoint == null && endpointUri == null) {
108            throw new IllegalArgumentException("Either endpoint or endpointUri must be configured");
109        }
110
111        if (endpoint == null) {
112            endpoint = camelContext.getEndpoint(endpointUri);
113        }
114
115        producer = endpoint.createProducer();
116        ServiceHelper.startService(producer);
117    }
118
119    @Override
120    protected void doStop() throws Exception {
121        ServiceHelper.stopService(producer);
122    }
123
124    @Override
125    public String toString() {
126        return "PublishEventNotifier[" + (endpoint != null ? endpoint : URISupport.sanitizeUri(endpointUri)) + "]";
127    }
128
129}