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.Processor; 026 import org.apache.camel.impl.ServiceSupport; 027 import org.apache.camel.util.ObjectHelper; 028 import org.apache.camel.util.ServiceHelper; 029 import org.apache.commons.logging.Log; 030 import org.apache.commons.logging.LogFactory; 031 032 /** 033 * A {@link Processor} which converts the inbound exchange to a method 034 * invocation on a POJO 035 * 036 * @version $Revision: 42414 $ 037 */ 038 public class BeanProcessor extends ServiceSupport implements Processor { 039 public static final String METHOD_NAME = "org.apache.camel.MethodName"; 040 private static final transient Log LOG = LogFactory.getLog(BeanProcessor.class); 041 042 private Method methodObject; 043 private String method; 044 private BeanHolder beanHolder; 045 046 public BeanProcessor(Object pojo, BeanInfo beanInfo) { 047 this(new ConstantBeanHolder(pojo, beanInfo)); 048 } 049 050 public BeanProcessor(Object pojo, CamelContext camelContext, ParameterMappingStrategy parameterMappingStrategy) { 051 this(pojo, new BeanInfo(camelContext, pojo.getClass(), parameterMappingStrategy)); 052 } 053 054 public BeanProcessor(Object pojo, CamelContext camelContext) { 055 this(pojo, camelContext, BeanInfo.createParameterMappingStrategy(camelContext)); 056 } 057 058 public BeanProcessor(BeanHolder beanHolder) { 059 this.beanHolder = beanHolder; 060 } 061 062 @Override 063 public String toString() { 064 String description = methodObject != null ? " " + methodObject : ""; 065 return "BeanProcessor[" + beanHolder + description + "]"; 066 } 067 068 public void process(Exchange exchange) throws Exception { 069 if (LOG.isDebugEnabled()) { 070 LOG.debug(">>>> invoking method for: " + exchange); 071 } 072 073 Object bean = beanHolder.getBean(); 074 exchange.setProperty("org.apache.camel.bean.BeanHolder", beanHolder); 075 076 Processor processor = getProcessor(); 077 BeanInfo beanInfo = beanHolder.getBeanInfo(); 078 079 // do we have a custom adapter for this POJO to a Processor 080 if (processor != null) { 081 processor.process(exchange); 082 return; 083 } 084 Message in = exchange.getIn(); 085 BeanInvocation beanInvoke = in.getBody(BeanInvocation.class); 086 if (beanInvoke != null) { 087 beanInvoke.invoke(bean, exchange); 088 return; 089 } 090 091 boolean isExplicitMethod = false; 092 String prevMethod = null; 093 MethodInvocation invocation; 094 if (methodObject != null) { 095 invocation = beanInfo.createInvocation(methodObject, bean, exchange); 096 } else { 097 // we just override the bean's invocation method name here 098 if (ObjectHelper.isNotNullAndNonEmpty(method)) { 099 prevMethod = in.getHeader(METHOD_NAME, String.class); 100 in.setHeader(METHOD_NAME, method); 101 isExplicitMethod = true; 102 } 103 invocation = beanInfo.createInvocation(bean, exchange); 104 } 105 if (invocation == null) { 106 throw new IllegalStateException("No method invocation could be created, " 107 + "no maching method could be found on: " + bean); 108 } 109 try { 110 Object value = invocation.proceed(); 111 if (value != null) { 112 exchange.getOut().setBody(value); 113 } 114 } catch (InvocationTargetException e) { 115 // lets unwrap the exception 116 Throwable cause = e.getCause(); 117 if (cause instanceof Exception) { 118 throw (Exception) cause; 119 } else { 120 // do not handle errors! 121 throw e; 122 } 123 } catch (Exception e) { 124 throw e; 125 } catch (Throwable throwable) { 126 throw new Exception(throwable); 127 } finally { 128 if (isExplicitMethod) { 129 in.setHeader(METHOD_NAME, prevMethod); 130 } 131 } 132 } 133 134 protected Processor getProcessor() { 135 return beanHolder.getProcessor(); 136 } 137 138 // Properties 139 // ----------------------------------------------------------------------- 140 141 public Method getMethodObject() { 142 return methodObject; 143 } 144 145 public void setMethodObject(Method methodObject) { 146 this.methodObject = methodObject; 147 } 148 149 public String getMethod() { 150 return method; 151 } 152 153 /** 154 * Sets the method name to use 155 */ 156 public void setMethod(String method) { 157 this.method = method; 158 } 159 160 /** 161 * Kept around for backwards compatibility, please use {@link #setMethod(String)} 162 * in future instead. 163 * 164 * @deprecated use {@link #setMethod(String)}. Will be removed in Camel 2.0. 165 */ 166 @Deprecated 167 public void setMethodName(String method) { 168 setMethod(method); 169 } 170 171 // Implementation methods 172 //------------------------------------------------------------------------- 173 protected void doStart() throws Exception { 174 ServiceHelper.startService(getProcessor()); 175 } 176 177 protected void doStop() throws Exception { 178 ServiceHelper.stopService(getProcessor()); 179 } 180 }