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.impl; 018 019import java.lang.reflect.Field; 020import java.lang.reflect.Method; 021 022import org.apache.camel.BeanInject; 023import org.apache.camel.CamelContext; 024import org.apache.camel.CamelContextAware; 025import org.apache.camel.EndpointInject; 026import org.apache.camel.Produce; 027import org.apache.camel.PropertyInject; 028import org.apache.camel.util.ObjectHelper; 029import org.apache.camel.util.ReflectionHelper; 030import org.slf4j.Logger; 031import org.slf4j.LoggerFactory; 032 033/** 034 * A bean post processor which implements the <a href="http://camel.apache.org/bean-integration.html">Bean Integration</a> 035 * features in Camel. Features such as the <a href="http://camel.apache.org/bean-injection.html">Bean Injection</a> of objects like 036 * {@link org.apache.camel.Endpoint} and 037 * {@link org.apache.camel.ProducerTemplate} together with support for 038 * <a href="http://camel.apache.org/pojo-consuming.html">POJO Consuming</a> via the 039 * {@link org.apache.camel.Consume} annotation along with 040 * <a href="http://camel.apache.org/pojo-producing.html">POJO Producing</a> via the 041 * {@link org.apache.camel.Produce} annotation along with other annotations such as 042 * {@link org.apache.camel.DynamicRouter} for creating <a href="http://camel.apache.org/dynamicrouter-annotation.html">a Dynamic router via annotations</a>. 043 * {@link org.apache.camel.RecipientList} for creating <a href="http://camel.apache.org/recipientlist-annotation.html">a Recipient List router via annotations</a>. 044 * {@link org.apache.camel.RoutingSlip} for creating <a href="http://camel.apache.org/routingslip-annotation.html">a Routing Slip router via annotations</a>. 045 * <p/> 046 * Components such as <tt>camel-spring</tt>, and <tt>camel-blueprint</tt> can leverage this post processor to hook in Camel 047 * bean post processing into their bean processing framework. 048 */ 049public class DefaultCamelBeanPostProcessor { 050 051 protected static final Logger LOG = LoggerFactory.getLogger(DefaultCamelBeanPostProcessor.class); 052 protected CamelPostProcessorHelper camelPostProcessorHelper; 053 protected CamelContext camelContext; 054 055 public DefaultCamelBeanPostProcessor() { 056 } 057 058 public DefaultCamelBeanPostProcessor(CamelContext camelContext) { 059 this.camelContext = camelContext; 060 } 061 062 /** 063 * Apply this post processor to the given new bean instance <i>before</i> any bean 064 * initialization callbacks (like <code>afterPropertiesSet</code> 065 * or a custom init-method). The bean will already be populated with property values. 066 * The returned bean instance may be a wrapper around the original. 067 * 068 * @param bean the new bean instance 069 * @param beanName the name of the bean 070 * @return the bean instance to use, either the original or a wrapped one; if 071 * <code>null</code>, no subsequent BeanPostProcessors will be invoked 072 * @throws Exception is thrown if error post processing bean 073 */ 074 public Object postProcessBeforeInitialization(Object bean, String beanName) throws Exception { 075 LOG.trace("Camel bean processing before initialization for bean: {}", beanName); 076 077 // some beans cannot be post processed at this given time, so we gotta check beforehand 078 if (!canPostProcessBean(bean, beanName)) { 079 return bean; 080 } 081 082 injectFields(bean, beanName); 083 injectMethods(bean, beanName); 084 085 if (bean instanceof CamelContextAware && canSetCamelContext(bean, beanName)) { 086 CamelContextAware contextAware = (CamelContextAware)bean; 087 CamelContext context = getOrLookupCamelContext(); 088 if (context == null) { 089 LOG.warn("No CamelContext defined yet so cannot inject into bean: " + beanName); 090 } else { 091 contextAware.setCamelContext(context); 092 } 093 } 094 095 return bean; 096 } 097 098 /** 099 * Apply this post processor to the given new bean instance <i>after</i> any bean 100 * initialization callbacks (like <code>afterPropertiesSet</code> 101 * or a custom init-method). The bean will already be populated with property values. 102 * The returned bean instance may be a wrapper around the original. 103 * 104 * @param bean the new bean instance 105 * @param beanName the name of the bean 106 * @return the bean instance to use, either the original or a wrapped one; if 107 * <code>null</code>, no subsequent BeanPostProcessors will be invoked 108 * @throws Exception is thrown if error post processing bean 109 */ 110 public Object postProcessAfterInitialization(Object bean, String beanName) throws Exception { 111 LOG.trace("Camel bean processing after initialization for bean: {}", beanName); 112 113 // some beans cannot be post processed at this given time, so we gotta check beforehand 114 if (!canPostProcessBean(bean, beanName)) { 115 return bean; 116 } 117 118 if (bean instanceof DefaultEndpoint) { 119 DefaultEndpoint defaultEndpoint = (DefaultEndpoint) bean; 120 defaultEndpoint.setEndpointUriIfNotSpecified(beanName); 121 } 122 123 return bean; 124 } 125 126 /** 127 * Strategy to get the {@link CamelContext} to use. 128 */ 129 public CamelContext getOrLookupCamelContext() { 130 return camelContext; 131 } 132 133 /** 134 * Strategy to get the {@link CamelPostProcessorHelper} 135 */ 136 public CamelPostProcessorHelper getPostProcessorHelper() { 137 if (camelPostProcessorHelper == null) { 138 camelPostProcessorHelper = new CamelPostProcessorHelper(getOrLookupCamelContext()); 139 } 140 return camelPostProcessorHelper; 141 } 142 143 protected boolean canPostProcessBean(Object bean, String beanName) { 144 return bean != null; 145 } 146 147 protected boolean canSetCamelContext(Object bean, String beanName) { 148 if (bean instanceof CamelContextAware) { 149 CamelContextAware camelContextAware = (CamelContextAware) bean; 150 CamelContext context = camelContextAware.getCamelContext(); 151 if (context != null) { 152 LOG.trace("CamelContext already set on bean with id [{}]. Will keep existing CamelContext on bean.", beanName); 153 return false; 154 } 155 } 156 157 return true; 158 } 159 160 /** 161 * A strategy method to allow implementations to perform some custom JBI 162 * based injection of the POJO 163 * 164 * @param bean the bean to be injected 165 */ 166 protected void injectFields(final Object bean, final String beanName) { 167 ReflectionHelper.doWithFields(bean.getClass(), new ReflectionHelper.FieldCallback() { 168 public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException { 169 PropertyInject propertyInject = field.getAnnotation(PropertyInject.class); 170 if (propertyInject != null && getPostProcessorHelper().matchContext(propertyInject.context())) { 171 injectFieldProperty(field, propertyInject.value(), propertyInject.defaultValue(), bean, beanName); 172 } 173 174 BeanInject beanInject = field.getAnnotation(BeanInject.class); 175 if (beanInject != null && getPostProcessorHelper().matchContext(beanInject.context())) { 176 injectFieldBean(field, beanInject.value(), bean, beanName); 177 } 178 179 EndpointInject endpointInject = field.getAnnotation(EndpointInject.class); 180 if (endpointInject != null && getPostProcessorHelper().matchContext(endpointInject.context())) { 181 injectField(field, endpointInject.uri(), endpointInject.ref(), endpointInject.property(), bean, beanName); 182 } 183 184 Produce produce = field.getAnnotation(Produce.class); 185 if (produce != null && getPostProcessorHelper().matchContext(produce.context())) { 186 injectField(field, produce.uri(), produce.ref(), produce.property(), bean, beanName); 187 } 188 } 189 }); 190 } 191 192 public void injectField(Field field, String endpointUri, String endpointRef, String endpointProperty, 193 Object bean, String beanName) { 194 ReflectionHelper.setField(field, bean, 195 getPostProcessorHelper().getInjectionValue(field.getType(), endpointUri, endpointRef, endpointProperty, 196 field.getName(), bean, beanName)); 197 } 198 199 public void injectFieldBean(Field field, String name, Object bean, String beanName) { 200 ReflectionHelper.setField(field, bean, 201 getPostProcessorHelper().getInjectionBeanValue(field.getType(), name)); 202 } 203 204 public void injectFieldProperty(Field field, String propertyName, String propertyDefaultValue, Object bean, String beanName) { 205 ReflectionHelper.setField(field, bean, 206 getPostProcessorHelper().getInjectionPropertyValue(field.getType(), propertyName, propertyDefaultValue, 207 field.getName(), bean, beanName)); 208 } 209 210 protected void injectMethods(final Object bean, final String beanName) { 211 ReflectionHelper.doWithMethods(bean.getClass(), new ReflectionHelper.MethodCallback() { 212 public void doWith(Method method) throws IllegalArgumentException, IllegalAccessException { 213 setterInjection(method, bean, beanName); 214 getPostProcessorHelper().consumerInjection(method, bean, beanName); 215 } 216 }); 217 } 218 219 protected void setterInjection(Method method, Object bean, String beanName) { 220 PropertyInject propertyInject = method.getAnnotation(PropertyInject.class); 221 if (propertyInject != null && getPostProcessorHelper().matchContext(propertyInject.context())) { 222 setterPropertyInjection(method, propertyInject.value(), propertyInject.defaultValue(), bean, beanName); 223 } 224 225 BeanInject beanInject = method.getAnnotation(BeanInject.class); 226 if (beanInject != null && getPostProcessorHelper().matchContext(beanInject.context())) { 227 setterBeanInjection(method, beanInject.value(), bean, beanName); 228 } 229 230 EndpointInject endpointInject = method.getAnnotation(EndpointInject.class); 231 if (endpointInject != null && getPostProcessorHelper().matchContext(endpointInject.context())) { 232 setterInjection(method, bean, beanName, endpointInject.uri(), endpointInject.ref(), endpointInject.property()); 233 } 234 235 Produce produce = method.getAnnotation(Produce.class); 236 if (produce != null && getPostProcessorHelper().matchContext(produce.context())) { 237 setterInjection(method, bean, beanName, produce.uri(), produce.ref(), produce.property()); 238 } 239 } 240 241 public void setterInjection(Method method, Object bean, String beanName, String endpointUri, String endpointRef, String endpointProperty) { 242 Class<?>[] parameterTypes = method.getParameterTypes(); 243 if (parameterTypes != null) { 244 if (parameterTypes.length != 1) { 245 LOG.warn("Ignoring badly annotated method for injection due to incorrect number of parameters: " + method); 246 } else { 247 String propertyName = ObjectHelper.getPropertyName(method); 248 Object value = getPostProcessorHelper().getInjectionValue(parameterTypes[0], endpointUri, endpointRef, endpointProperty, 249 propertyName, bean, beanName); 250 ObjectHelper.invokeMethod(method, bean, value); 251 } 252 } 253 } 254 255 public void setterPropertyInjection(Method method, String propertyValue, String propertyDefaultValue, 256 Object bean, String beanName) { 257 Class<?>[] parameterTypes = method.getParameterTypes(); 258 if (parameterTypes != null) { 259 if (parameterTypes.length != 1) { 260 LOG.warn("Ignoring badly annotated method for injection due to incorrect number of parameters: " + method); 261 } else { 262 String propertyName = ObjectHelper.getPropertyName(method); 263 Object value = getPostProcessorHelper().getInjectionPropertyValue(parameterTypes[0], propertyValue, propertyDefaultValue, propertyName, bean, beanName); 264 ObjectHelper.invokeMethod(method, bean, value); 265 } 266 } 267 } 268 269 public void setterBeanInjection(Method method, String name, Object bean, String beanName) { 270 Class<?>[] parameterTypes = method.getParameterTypes(); 271 if (parameterTypes != null) { 272 if (parameterTypes.length != 1) { 273 LOG.warn("Ignoring badly annotated method for injection due to incorrect number of parameters: " + method); 274 } else { 275 Object value = getPostProcessorHelper().getInjectionBeanValue(parameterTypes[0], name); 276 ObjectHelper.invokeMethod(method, bean, value); 277 } 278 } 279 } 280 281}