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.NoTypeConversionAvailableException;
021 import org.apache.camel.Processor;
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 import static org.apache.camel.util.ObjectHelper.wrapRuntimeCamelException;
046
047 /**
048 * A Spring aware implementation of {@link org.apache.camel.CamelContext} which
049 * will automatically register itself with Springs lifecycle methods plus allows
050 * spring to be used to customize a any <a
051 * href="http://activemq.apache.org/camel/type-converter.html">Type Converters</a>
052 * as well as supporting accessing components and beans via the Spring
053 * {@link ApplicationContext}
054 *
055 * @version $Revision: 705853 $
056 */
057 public class SpringCamelContext extends DefaultCamelContext implements InitializingBean, DisposableBean,
058 ApplicationContextAware, ApplicationListener {
059 private static final transient Log LOG = LogFactory.getLog(SpringCamelContext.class);
060 private ApplicationContext applicationContext;
061 private EventEndpoint eventEndpoint;
062 private boolean shouldStartContext =
063 ObjectHelper.getSystemProperty("shouldStartContext", Boolean.TRUE); // start context by default
064
065 public SpringCamelContext() {
066 }
067
068 public SpringCamelContext(ApplicationContext applicationContext) {
069 setApplicationContext(applicationContext);
070 }
071
072 public static SpringCamelContext springCamelContext(ApplicationContext applicationContext)
073 throws Exception {
074 // lets try and look up a configured camel context in the context
075 String[] names = applicationContext.getBeanNamesForType(SpringCamelContext.class);
076 if (names.length == 1) {
077 return (SpringCamelContext)applicationContext.getBean(names[0], SpringCamelContext.class);
078 }
079 SpringCamelContext answer = new SpringCamelContext();
080 answer.setApplicationContext(applicationContext);
081 answer.afterPropertiesSet();
082 return answer;
083 }
084
085
086 public static SpringCamelContext springCamelContext(String configLocations) throws Exception {
087 return springCamelContext(new ClassPathXmlApplicationContext(configLocations));
088 }
089
090 public void afterPropertiesSet() throws Exception {
091 maybeStart();
092 }
093
094 private void maybeStart() throws Exception {
095 if (getShouldStartContext()) {
096 LOG.debug("Starting the CamelContext now that the ApplicationContext has started");
097 start();
098 } else {
099 LOG.debug("Not starting the CamelContext since shouldStartContext property was true.");
100 }
101 }
102
103 public void destroy() throws Exception {
104 stop();
105 }
106
107 public void onApplicationEvent(ApplicationEvent event) {
108 if (LOG.isDebugEnabled()) {
109 LOG.debug("Publishing spring-event: " + event);
110 }
111
112 if (event instanceof ContextRefreshedEvent) {
113 // now lets start the CamelContext so that all its possible
114 // dependencies are initialized
115 try {
116 maybeStart();
117 } catch (RuntimeException e) {
118 throw e;
119 } catch (Exception e) {
120 throw wrapRuntimeCamelException(e);
121 }
122 if (eventEndpoint != null) {
123 eventEndpoint.onApplicationEvent(event);
124 }
125 } else {
126 if (eventEndpoint != null) {
127 eventEndpoint.onApplicationEvent(event);
128 } else {
129 LOG.warn("No spring-event endpoint enabled for: " + event);
130 }
131 }
132 }
133
134 // Properties
135 // -----------------------------------------------------------------------
136
137 public ApplicationContext getApplicationContext() {
138 return applicationContext;
139 }
140
141 public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
142 this.applicationContext = applicationContext;
143
144 if (applicationContext instanceof ConfigurableApplicationContext) {
145 addComponent("spring-event", new EventComponent(applicationContext));
146 }
147 }
148
149 public EventEndpoint getEventEndpoint() {
150 return eventEndpoint;
151 }
152
153 public void setEventEndpoint(EventEndpoint eventEndpoint) {
154 this.eventEndpoint = eventEndpoint;
155 }
156
157 // Implementation methods
158 // -----------------------------------------------------------------------
159
160 @Override
161 protected void doStart() throws Exception {
162 maybeDoStart();
163 }
164
165 protected void maybeDoStart() throws Exception {
166 if (getShouldStartContext()) {
167 super.doStart();
168 if (eventEndpoint == null) {
169 eventEndpoint = createEventEndpoint();
170 }
171 }
172 }
173
174 @Override
175 protected Injector createInjector() {
176 if (applicationContext instanceof ConfigurableApplicationContext) {
177 return new SpringInjector((ConfigurableApplicationContext)applicationContext);
178 } else {
179 LOG.warn("Cannot use SpringInjector as applicationContext is not a ConfigurableApplicationContext as its: "
180 + applicationContext);
181 return super.createInjector();
182 }
183 }
184
185 protected EventEndpoint createEventEndpoint() {
186 EventEndpoint endpoint = getEndpoint("spring-event:default", EventEndpoint.class);
187 return endpoint;
188 }
189
190 protected Endpoint convertBeanToEndpoint(String uri, Object bean) {
191 // We will use the type convert to build the endpoint first
192 try {
193 Endpoint endpoint = getTypeConverter().convertTo(Endpoint.class, bean);
194 if (endpoint != null) {
195 endpoint.setCamelContext(this);
196 return endpoint;
197 }
198 } catch (NoTypeConversionAvailableException ex) {
199 // ignore, handled below
200 }
201
202 return new ProcessorEndpoint(uri, this, new BeanProcessor(bean, this));
203 }
204
205 @Override
206 protected Registry createRegistry() {
207 return new ApplicationContextRegistry(getApplicationContext());
208 }
209
210 public void setShouldStartContext(boolean shouldStartContext) {
211 this.shouldStartContext = shouldStartContext;
212 }
213
214 public boolean getShouldStartContext() {
215 return shouldStartContext;
216 }
217 }