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.component.bean;
018
019 import java.lang.reflect.InvocationTargetException;
020 import java.lang.reflect.Method;
021
022 import org.apache.camel.CamelContext;
023 import org.apache.camel.Exchange;
024 import org.apache.camel.Message;
025 import org.apache.camel.NoTypeConversionAvailableException;
026 import org.apache.camel.Processor;
027 import org.apache.camel.impl.ServiceSupport;
028 import org.apache.camel.util.ObjectHelper;
029 import org.apache.camel.util.ServiceHelper;
030 import org.apache.commons.logging.Log;
031 import org.apache.commons.logging.LogFactory;
032
033 /**
034 * A {@link Processor} which converts the inbound exchange to a method
035 * invocation on a POJO
036 *
037 * @version $Revision: 52200 $
038 */
039 public class BeanProcessor extends ServiceSupport implements Processor {
040 public static final String METHOD_NAME = "org.apache.camel.MethodName";
041 public static final String MULTI_PARAMETER_ARRAY = "org.apache.camel.MultiParameterArray";
042 private static final transient Log LOG = LogFactory.getLog(BeanProcessor.class);
043
044 private boolean multiParameterArray;
045 private Method methodObject;
046 private String method;
047 private BeanHolder beanHolder;
048
049 public BeanProcessor(Object pojo, BeanInfo beanInfo) {
050 this(new ConstantBeanHolder(pojo, beanInfo));
051 }
052
053 public BeanProcessor(Object pojo, CamelContext camelContext, ParameterMappingStrategy parameterMappingStrategy) {
054 this(pojo, new BeanInfo(camelContext, pojo.getClass(), parameterMappingStrategy));
055 }
056
057 public BeanProcessor(Object pojo, CamelContext camelContext) {
058 this(pojo, camelContext, BeanInfo.createParameterMappingStrategy(camelContext));
059 }
060
061 public BeanProcessor(BeanHolder beanHolder) {
062 this.beanHolder = beanHolder;
063 }
064
065 @Override
066 public String toString() {
067 String description = methodObject != null ? " " + methodObject : "";
068 return "BeanProcessor[" + beanHolder + description + "]";
069 }
070
071 public void process(Exchange exchange) throws Exception {
072 Object bean = beanHolder.getBean();
073 exchange.setProperty("org.apache.camel.bean.BeanHolder", beanHolder);
074
075 Processor processor = getProcessor();
076 BeanInfo beanInfo = beanHolder.getBeanInfo();
077
078 // do we have a custom adapter for this POJO to a Processor
079 if (processor != null) {
080 processor.process(exchange);
081 return;
082 }
083 Message in = exchange.getIn();
084
085 if (in.getHeader(MULTI_PARAMETER_ARRAY) == null) {
086 in.setHeader(MULTI_PARAMETER_ARRAY, isMultiParameterArray());
087 }
088
089 try {
090 BeanInvocation beanInvoke = in.getBody(BeanInvocation.class);
091 if (beanInvoke != null) {
092 beanInvoke.invoke(bean, exchange);
093 return;
094 }
095 } catch (NoTypeConversionAvailableException ex) {
096 // ignore, body is not a BeanInvocation
097 }
098
099 boolean isExplicitMethod = false;
100 String prevMethod = null;
101 MethodInvocation invocation;
102 if (methodObject != null) {
103 invocation = beanInfo.createInvocation(methodObject, bean, exchange);
104 } else {
105 // we just override the bean's invocation method name here
106 if (ObjectHelper.isNotNullAndNonEmpty(method)) {
107 prevMethod = in.getHeader(METHOD_NAME, String.class);
108 in.setHeader(METHOD_NAME, method);
109 isExplicitMethod = true;
110 }
111 invocation = beanInfo.createInvocation(bean, exchange);
112 }
113 if (invocation == null) {
114 throw new IllegalStateException(
115 "No method invocation could be created, no maching method could be found on: " + bean);
116 }
117 try {
118 Object value = invocation.proceed();
119 if (value != null) {
120 if (exchange.getPattern().isOutCapable()) {
121 // force out creating if not already created (as its lazy)
122 if (LOG.isDebugEnabled()) {
123 LOG.debug("Setting bean invocation result on the OUT message: " + value);
124 }
125 exchange.getOut(true).setBody(value);
126 } else {
127 // if not out then set it on the in
128 if (LOG.isDebugEnabled()) {
129 LOG.debug("Setting bean invocation result on the IN message: " + value);
130 }
131 exchange.getIn().setBody(value);
132 }
133 }
134 } catch (InvocationTargetException e) {
135 // lets unwrap the exception
136 Throwable cause = e.getCause();
137 if (cause instanceof Exception) {
138 throw (Exception) cause;
139 } else {
140 // do not handle errors!
141 throw e;
142 }
143 } catch (Exception e) {
144 throw e;
145 } catch (Throwable throwable) {
146 throw new Exception(throwable);
147 } finally {
148 if (isExplicitMethod) {
149 in.setHeader(METHOD_NAME, prevMethod);
150 }
151 }
152 }
153
154 protected Processor getProcessor() {
155 return beanHolder.getProcessor();
156 }
157
158 // Properties
159 // -----------------------------------------------------------------------
160
161 public Method getMethodObject() {
162 return methodObject;
163 }
164
165 public void setMethodObject(Method methodObject) {
166 this.methodObject = methodObject;
167 }
168
169 public String getMethod() {
170 return method;
171 }
172
173 public boolean isMultiParameterArray() {
174 return multiParameterArray;
175 }
176
177 public void setMultiParameterArray(boolean mpArray) {
178 multiParameterArray = mpArray;
179 }
180
181 /**
182 * Sets the method name to use
183 */
184 public void setMethod(String method) {
185 this.method = method;
186 }
187
188 /**
189 * Kept around for backwards compatibility, please use {@link #setMethod(String)}
190 * in future instead.
191 *
192 * @deprecated use {@link #setMethod(String)}. Will be removed in Camel 2.0.
193 */
194 @Deprecated
195 public void setMethodName(String method) {
196 setMethod(method);
197 }
198
199 // Implementation methods
200 //-------------------------------------------------------------------------
201 protected void doStart() throws Exception {
202 ServiceHelper.startService(getProcessor());
203 }
204
205 protected void doStop() throws Exception {
206 ServiceHelper.stopService(getProcessor());
207 }
208 }