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.spring;
018
019 import org.apache.camel.Endpoint;
020 import org.apache.camel.Processor;
021 import org.apache.camel.RuntimeCamelException;
022 import org.apache.camel.component.bean.BeanProcessor;
023 import org.apache.camel.component.event.EventComponent;
024 import org.apache.camel.component.event.EventEndpoint;
025 import org.apache.camel.impl.DefaultCamelContext;
026 import org.apache.camel.impl.ProcessorEndpoint;
027 import org.apache.camel.spi.Injector;
028 import org.apache.camel.spi.Registry;
029 import org.apache.camel.spring.spi.ApplicationContextRegistry;
030 import org.apache.camel.spring.spi.SpringInjector;
031 import org.apache.camel.util.ObjectHelper;
032 import org.apache.commons.logging.Log;
033 import org.apache.commons.logging.LogFactory;
034 import org.springframework.beans.BeansException;
035 import org.springframework.beans.factory.DisposableBean;
036 import org.springframework.beans.factory.InitializingBean;
037 import org.springframework.context.ApplicationContext;
038 import org.springframework.context.ApplicationContextAware;
039 import org.springframework.context.ApplicationEvent;
040 import org.springframework.context.ApplicationListener;
041 import org.springframework.context.ConfigurableApplicationContext;
042 import org.springframework.context.event.ContextRefreshedEvent;
043 import org.springframework.context.support.ClassPathXmlApplicationContext;
044
045 /**
046 * A Spring aware implementation of {@link org.apache.camel.CamelContext} which
047 * will automatically register itself with Springs lifecycle methods plus allows
048 * spring to be used to customize a any <a
049 * href="http://activemq.apache.org/camel/type-converter.html">Type Converters</a>
050 * as well as supporting accessing components and beans via the Spring
051 * {@link ApplicationContext}
052 *
053 * @version $Revision: 46148 $
054 */
055 public class SpringCamelContext extends DefaultCamelContext implements InitializingBean, DisposableBean,
056 ApplicationContextAware, ApplicationListener {
057 private static final transient Log LOG = LogFactory.getLog(SpringCamelContext.class);
058 private ApplicationContext applicationContext;
059 private EventEndpoint eventEndpoint;
060 private boolean shouldStartContext =
061 ObjectHelper.getSystemProperty("shouldStartContext", Boolean.TRUE); // start context by default
062
063 public SpringCamelContext() {
064 }
065
066 public SpringCamelContext(ApplicationContext applicationContext) {
067 setApplicationContext(applicationContext);
068 }
069
070 public static SpringCamelContext springCamelContext(ApplicationContext applicationContext)
071 throws Exception {
072 // lets try and look up a configured camel context in the context
073 String[] names = applicationContext.getBeanNamesForType(SpringCamelContext.class);
074 if (names.length == 1) {
075 return (SpringCamelContext)applicationContext.getBean(names[0], SpringCamelContext.class);
076 }
077 SpringCamelContext answer = new SpringCamelContext();
078 answer.setApplicationContext(applicationContext);
079 answer.afterPropertiesSet();
080 return answer;
081 }
082
083
084 public static SpringCamelContext springCamelContext(String configLocations) throws Exception {
085 return springCamelContext(new ClassPathXmlApplicationContext(configLocations));
086 }
087
088 public void afterPropertiesSet() throws Exception {
089 maybeStart();
090 }
091
092 private void maybeStart() throws Exception {
093 if (getShouldStartContext()) {
094 LOG.debug("Starting the CamelContext now that the ApplicationContext has started");
095 start();
096 } else {
097 LOG.debug("Not starting the CamelContext since shouldStartContext property was true.");
098 }
099 }
100
101 public void destroy() throws Exception {
102 stop();
103 }
104
105 public void onApplicationEvent(ApplicationEvent event) {
106 if (LOG.isDebugEnabled()) {
107 LOG.debug("Publishing event: " + event);
108 }
109
110 if (event instanceof ContextRefreshedEvent) {
111 // now lets start the CamelContext so that all its possible
112 // dependencies are initialized
113 try {
114 maybeStart();
115 } catch (RuntimeException e) {
116 throw e;
117 } catch (Exception e) {
118 throw new RuntimeCamelException(e);
119 }
120 if (eventEndpoint != null) {
121 eventEndpoint.onApplicationEvent(event);
122 }
123 } else {
124 if (eventEndpoint != null) {
125 eventEndpoint.onApplicationEvent(event);
126 } else {
127 LOG.warn("No eventEndpoint enabled for event: " + event);
128 }
129 }
130 }
131
132 // Properties
133 // -----------------------------------------------------------------------
134
135 public ApplicationContext getApplicationContext() {
136 return applicationContext;
137 }
138
139 public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
140 this.applicationContext = applicationContext;
141
142 if (applicationContext instanceof ConfigurableApplicationContext) {
143 addComponent("event", new EventComponent(applicationContext));
144 }
145 }
146
147 public EventEndpoint getEventEndpoint() {
148 return eventEndpoint;
149 }
150
151 public void setEventEndpoint(EventEndpoint eventEndpoint) {
152 this.eventEndpoint = eventEndpoint;
153 }
154
155 // Implementation methods
156 // -----------------------------------------------------------------------
157
158 @Override
159 protected void doStart() throws Exception {
160 maybeDoStart();
161 }
162
163 protected void maybeDoStart() throws Exception {
164 if (getShouldStartContext()) {
165 super.doStart();
166 if (eventEndpoint == null) {
167 eventEndpoint = createEventEndpoint();
168 }
169 }
170 }
171
172 @Override
173 protected Injector createInjector() {
174 if (applicationContext instanceof ConfigurableApplicationContext) {
175 return new SpringInjector((ConfigurableApplicationContext)applicationContext);
176 } else {
177 LOG.warn("Cannot use SpringInjector as applicationContext is not a ConfigurableApplicationContext as its: "
178 + applicationContext);
179 return super.createInjector();
180 }
181 }
182
183 protected EventEndpoint createEventEndpoint() {
184 EventEndpoint endpoint = getEndpoint("event:default", EventEndpoint.class);
185 return endpoint;
186 }
187
188 protected Endpoint convertBeanToEndpoint(String uri, Object bean) {
189 //We will use the type convert to build the endpoint first
190 Endpoint endpoint = getTypeConverter().convertTo(Endpoint.class, bean);
191 if (endpoint != null) {
192 endpoint.setCamelContext(this);
193 return endpoint;
194 }
195 Processor processor = new BeanProcessor(bean, this);
196 return new ProcessorEndpoint(uri, this, processor);
197 }
198
199 @Override
200 protected Registry createRegistry() {
201 return new ApplicationContextRegistry(getApplicationContext());
202 }
203
204 public void setShouldStartContext(boolean shouldStartContext) {
205 this.shouldStartContext = shouldStartContext;
206 }
207
208 public boolean getShouldStartContext() {
209 return shouldStartContext;
210 }
211 }