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 }