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.CamelContextHelper; 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 import static org.apache.camel.util.ObjectHelper.isNullOrBlank; 033 034 /** 035 * A {@link Processor} which converts the inbound exchange to a method 036 * invocation on a POJO 037 * 038 * @version $Revision: 36321 $ 039 */ 040 public class BeanProcessor extends ServiceSupport implements Processor { 041 public static final String METHOD_NAME = "org.apache.camel.MethodName"; 042 private static final Log LOG = LogFactory.getLog(BeanProcessor.class); 043 044 private Method methodObject; 045 private String method; 046 private BeanHolder beanHolder; 047 048 public BeanProcessor(Object pojo, BeanInfo beanInfo) { 049 this(new ConstantBeanHolder(pojo, beanInfo)); 050 } 051 052 public BeanProcessor(Object pojo, CamelContext camelContext, ParameterMappingStrategy parameterMappingStrategy) { 053 this(pojo, new BeanInfo(camelContext, pojo.getClass(), parameterMappingStrategy)); 054 } 055 056 public BeanProcessor(Object pojo, CamelContext camelContext) { 057 this(pojo, camelContext, BeanInfo.createParameterMappingStrategy(camelContext)); 058 } 059 060 public BeanProcessor(BeanHolder beanHolder) { 061 this.beanHolder = beanHolder; 062 } 063 064 @Override 065 public String toString() { 066 String description = methodObject != null ? " " + methodObject : ""; 067 return "BeanProcessor[" + beanHolder + description + "]"; 068 } 069 070 public void process(Exchange exchange) throws Exception { 071 if (LOG.isDebugEnabled()) { 072 LOG.debug(">>>> invoking method for: " + exchange); 073 } 074 075 Object bean = beanHolder.getBean(); 076 exchange.setProperty("CamelBean", bean); 077 078 Processor processor = getProcessor(); 079 BeanInfo beanInfo = beanHolder.getBeanInfo(); 080 081 // do we have a custom adapter for this POJO to a Processor 082 if (processor != null) { 083 processor.process(exchange); 084 return; 085 } 086 Message in = exchange.getIn(); 087 BeanInvocation beanInvoke = in.getBody(BeanInvocation.class); 088 if (beanInvoke != null) { 089 beanInvoke.invoke(bean, exchange); 090 return; 091 } 092 093 boolean isExplicitMethod = false; 094 String prevMethod = null; 095 MethodInvocation invocation; 096 if (methodObject != null) { 097 invocation = beanInfo.createInvocation(methodObject, bean, exchange); 098 } else { 099 // we just override the bean's invocation method name here 100 if (ObjectHelper.isNotNullAndNonEmpty(method)) { 101 prevMethod = in.getHeader(METHOD_NAME, String.class); 102 in.setHeader(METHOD_NAME, method); 103 isExplicitMethod = true; 104 } 105 invocation = beanInfo.createInvocation(bean, exchange); 106 } 107 if (invocation == null) { 108 throw new IllegalStateException("No method invocation could be created, " 109 + "no maching method could be found on: " + bean); 110 } 111 try { 112 Object value = invocation.proceed(); 113 if (value != null) { 114 exchange.getOut().setBody(value); 115 } 116 } catch (InvocationTargetException e) { 117 // lets unwrap the exception 118 Throwable cause = e.getCause(); 119 if (cause instanceof Exception) { 120 throw (Exception) cause; 121 } else { 122 // do not handle errors! 123 throw e; 124 } 125 } catch (Exception e) { 126 throw e; 127 } catch (Throwable throwable) { 128 throw new Exception(throwable); 129 } finally { 130 if (isExplicitMethod) { 131 in.setHeader(METHOD_NAME, prevMethod); 132 } 133 } 134 } 135 136 protected Processor getProcessor() { 137 return beanHolder.getProcessor(); 138 } 139 140 // Properties 141 // ----------------------------------------------------------------------- 142 143 public Method getMethodObject() { 144 return methodObject; 145 } 146 147 public void setMethodObject(Method methodObject) { 148 this.methodObject = methodObject; 149 } 150 151 public String getMethod() { 152 return method; 153 } 154 155 /** 156 * Sets the method name to use 157 */ 158 public void setMethod(String method) { 159 this.method = method; 160 } 161 162 /** 163 * Kept around for backwards compatibility, please use {@link #setMethod(String)} 164 * in future instead. 165 * 166 * @deprecated 167 * @see #setMethod(String) 168 * @param method 169 */ 170 public void setMethodName(String method) { 171 setMethod(method); 172 } 173 174 // Implementation methods 175 //------------------------------------------------------------------------- 176 protected void doStart() throws Exception { 177 ServiceHelper.startService(getProcessor()); 178 } 179 180 protected void doStop() throws Exception { 181 ServiceHelper.stopService(getProcessor()); 182 } 183 }