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.component.bean.BeanProcessor;
022 import org.apache.camel.component.event.EventComponent;
023 import org.apache.camel.component.event.EventEndpoint;
024 import org.apache.camel.impl.DefaultCamelContext;
025 import org.apache.camel.impl.ProcessorEndpoint;
026 import org.apache.camel.spi.Injector;
027 import org.apache.camel.spi.Registry;
028 import org.apache.camel.spring.spi.ApplicationContextRegistry;
029 import org.apache.camel.spring.spi.SpringInjector;
030 import org.apache.camel.util.ObjectHelper;
031 import org.apache.commons.logging.Log;
032 import org.apache.commons.logging.LogFactory;
033 import org.springframework.beans.BeansException;
034 import org.springframework.beans.factory.DisposableBean;
035 import org.springframework.beans.factory.InitializingBean;
036 import org.springframework.context.ApplicationContext;
037 import org.springframework.context.ApplicationContextAware;
038 import org.springframework.context.ApplicationEvent;
039 import org.springframework.context.ApplicationListener;
040 import org.springframework.context.ConfigurableApplicationContext;
041 import org.springframework.context.event.ContextRefreshedEvent;
042 import org.springframework.context.support.ClassPathXmlApplicationContext;
043
044 import static org.apache.camel.util.ObjectHelper.wrapRuntimeCamelException;
045
046 /**
047 * A Spring aware implementation of {@link org.apache.camel.CamelContext} which
048 * will automatically register itself with Springs lifecycle methods plus allows
049 * spring to be used to customize a any <a
050 * href="http://activemq.apache.org/camel/type-converter.html">Type Converters</a>
051 * as well as supporting accessing components and beans via the Spring
052 * {@link ApplicationContext}
053 *
054 * @version $Revision: 732209 $
055 */
056 public class SpringCamelContext extends DefaultCamelContext implements InitializingBean, DisposableBean,
057 ApplicationContextAware, ApplicationListener {
058 private static final transient Log LOG = LogFactory.getLog(SpringCamelContext.class);
059 private ApplicationContext applicationContext;
060 private EventEndpoint eventEndpoint;
061 private boolean shouldStartContext =
062 ObjectHelper.getSystemProperty("shouldStartContext", Boolean.TRUE); // start context by default
063
064 public SpringCamelContext() {
065 }
066
067 public SpringCamelContext(ApplicationContext applicationContext) {
068 setApplicationContext(applicationContext);
069 }
070
071 public static SpringCamelContext springCamelContext(ApplicationContext applicationContext)
072 throws Exception {
073 // lets try and look up a configured camel context in the context
074 String[] names = applicationContext.getBeanNamesForType(SpringCamelContext.class);
075 if (names.length == 1) {
076 return (SpringCamelContext)applicationContext.getBean(names[0], SpringCamelContext.class);
077 }
078 SpringCamelContext answer = new SpringCamelContext();
079 answer.setApplicationContext(applicationContext);
080 answer.afterPropertiesSet();
081 return answer;
082 }
083
084
085 public static SpringCamelContext springCamelContext(String configLocations) throws Exception {
086 return springCamelContext(new ClassPathXmlApplicationContext(configLocations));
087 }
088
089 public void afterPropertiesSet() throws Exception {
090 maybeStart();
091 }
092
093 private void maybeStart() throws Exception {
094 if (getShouldStartContext()) {
095 LOG.debug("Starting the CamelContext now that the ApplicationContext has started");
096 start();
097 } else {
098 LOG.debug("Not starting the CamelContext since shouldStartContext property was false.");
099 }
100 }
101
102 public void destroy() throws Exception {
103 stop();
104 }
105
106 public void onApplicationEvent(ApplicationEvent event) {
107 if (LOG.isDebugEnabled()) {
108 LOG.debug("Publishing spring-event: " + event);
109 }
110
111 if (event instanceof ContextRefreshedEvent) {
112 // now lets start the CamelContext so that all its possible
113 // dependencies are initialized
114 try {
115 maybeStart();
116 } catch (RuntimeException e) {
117 throw e;
118 } catch (Exception e) {
119 throw wrapRuntimeCamelException(e);
120 }
121 if (eventEndpoint != null) {
122 eventEndpoint.onApplicationEvent(event);
123 }
124 } else {
125 if (eventEndpoint != null) {
126 eventEndpoint.onApplicationEvent(event);
127 } else {
128 LOG.warn("No spring-event endpoint enabled for: " + event);
129 }
130 }
131 }
132
133 // Properties
134 // -----------------------------------------------------------------------
135
136 public ApplicationContext getApplicationContext() {
137 return applicationContext;
138 }
139
140 public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
141 this.applicationContext = applicationContext;
142
143 if (applicationContext instanceof ConfigurableApplicationContext) {
144 addComponent("spring-event", new EventComponent(applicationContext));
145 }
146 }
147
148 public EventEndpoint getEventEndpoint() {
149 return eventEndpoint;
150 }
151
152 public void setEventEndpoint(EventEndpoint eventEndpoint) {
153 this.eventEndpoint = eventEndpoint;
154 }
155
156 // Implementation methods
157 // -----------------------------------------------------------------------
158
159 @Override
160 protected void doStart() throws Exception {
161 maybeDoStart();
162 }
163
164 protected void maybeDoStart() throws Exception {
165 if (getShouldStartContext()) {
166 super.doStart();
167 if (eventEndpoint == null) {
168 eventEndpoint = createEventEndpoint();
169 }
170 }
171 }
172
173 @Override
174 protected Injector createInjector() {
175 if (applicationContext instanceof ConfigurableApplicationContext) {
176 return new SpringInjector((ConfigurableApplicationContext)applicationContext);
177 } else {
178 LOG.warn("Cannot use SpringInjector as applicationContext is not a ConfigurableApplicationContext as its: "
179 + applicationContext);
180 return super.createInjector();
181 }
182 }
183
184 protected EventEndpoint createEventEndpoint() {
185 EventEndpoint endpoint = getEndpoint("spring-event:default", EventEndpoint.class);
186 return endpoint;
187 }
188
189 protected Endpoint convertBeanToEndpoint(String uri, Object bean) {
190 // We will use the type convert to build the endpoint first
191 try {
192 Endpoint endpoint = getTypeConverter().convertTo(Endpoint.class, bean);
193 if (endpoint != null) {
194 endpoint.setCamelContext(this);
195 return endpoint;
196 }
197 } catch (NoTypeConversionAvailableException ex) {
198 // ignore, handled below
199 }
200
201 return new ProcessorEndpoint(uri, this, new BeanProcessor(bean, this));
202 }
203
204 @Override
205 protected Registry createRegistry() {
206 return new ApplicationContextRegistry(getApplicationContext());
207 }
208
209 public void setShouldStartContext(boolean shouldStartContext) {
210 this.shouldStartContext = shouldStartContext;
211 }
212
213 public boolean getShouldStartContext() {
214 return shouldStartContext;
215 }
216
217 }