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; 018 019 import java.util.Map; 020 021 import org.apache.camel.spi.UnitOfWork; 022 023 /** 024 * The base message exchange interface providing access to the request, response 025 * and fault {@link Message} instances. Different providers such as JMS, JBI, 026 * CXF and HTTP can provide their own derived API to expose the underlying 027 * transport semantics to avoid the leaky abstractions of generic APIs. 028 * 029 * @version $Revision: 47622 $ 030 */ 031 public interface Exchange { 032 033 String CHARSET_NAME = "org.apache.camel.Exchange.CharsetName"; 034 035 /** 036 * Returns the {@link ExchangePattern} (MEP) of this exchange. 037 * 038 * @return the message exchange pattern of this exchange 039 */ 040 ExchangePattern getPattern(); 041 042 /** 043 * Allows the {@link ExchangePattern} (MEP) of this exchange to be customized. 044 * 045 * This typically won't be required as an exchange can be created with a specific MEP 046 * by calling {@link Endpoint#createExchange(ExchangePattern)} but it is here just in case 047 * it is needed. 048 */ 049 void setPattern(ExchangePattern pattern); 050 051 /** 052 * Returns a property associated with this exchange by name 053 * 054 * @param name the name of the property 055 * @return the value of the given header or null if there is no property for 056 * the given name 057 */ 058 Object getProperty(String name); 059 060 /** 061 * Returns a property associated with this exchange by name and specifying 062 * the type required 063 * 064 * @param name the name of the property 065 * @param type the type of the property 066 * @return the value of the given header or null if there is no property for 067 * the given name or null if it cannot be converted to the given 068 * type 069 */ 070 <T> T getProperty(String name, Class<T> type); 071 072 /** 073 * Sets a property on the exchange 074 * 075 * @param name of the property 076 * @param value to associate with the name 077 */ 078 void setProperty(String name, Object value); 079 080 /** 081 * Removes the given property on the exchange 082 * 083 * @param name of the property 084 * @return the old value of the property 085 */ 086 Object removeProperty(String name); 087 088 /** 089 * Returns all of the properties associated with the exchange 090 * 091 * @return all the headers in a Map 092 */ 093 Map<String, Object> getProperties(); 094 095 /** 096 * Returns the inbound request message 097 * 098 * @return the message 099 */ 100 Message getIn(); 101 102 /** 103 * Sets the inbound message instance 104 * 105 * @param in the inbound message 106 */ 107 void setIn(Message in); 108 109 /** 110 * Returns the outbound message, lazily creating one if one has not already 111 * been associated with this exchange. If you want to inspect this property 112 * but not force lazy creation then invoke the {@link #getOut(boolean)} 113 * method passing in <tt>false</tt> 114 * 115 * @return the response 116 */ 117 Message getOut(); 118 119 /** 120 * Returns the outbound message; optionally lazily creating one if one has 121 * not been associated with this exchange 122 * 123 * @return the response 124 */ 125 Message getOut(boolean lazyCreate); 126 127 /** 128 * Sets the outbound message 129 * 130 * @param out the outbound message 131 */ 132 void setOut(Message out); 133 134 /** 135 * Returns the fault message 136 * 137 * @return the fault 138 */ 139 Message getFault(); 140 141 /** 142 * Returns the fault message; optionally lazily creating one if one has 143 * not been associated with this exchange 144 * 145 * @param lazyCreate <tt>true</tt> will lazy create the fault message 146 * 147 * @return the fault 148 */ 149 Message getFault(boolean lazyCreate); 150 151 /** 152 * Returns the exception associated with this exchange 153 * 154 * @return the exception (or null if no faults) 155 */ 156 Throwable getException(); 157 158 /** 159 * Sets the exception associated with this exchange 160 * 161 * @param e the caused exception 162 */ 163 void setException(Throwable e); 164 165 /** 166 * Returns true if this exchange failed due to either an exception or fault 167 * 168 * @return true if this exchange failed due to either an exception or fault 169 * @see Exchange#getException() 170 * @see Exchange#getFault() 171 */ 172 boolean isFailed(); 173 174 /** 175 * Returns true if this exchange is transacted 176 */ 177 boolean isTransacted(); 178 179 /** 180 * Returns the container so that a processor can resolve endpoints from URIs 181 * 182 * @return the container which owns this exchange 183 */ 184 CamelContext getContext(); 185 186 /** 187 * Creates a new exchange instance with empty messages, headers and properties 188 */ 189 Exchange newInstance(); 190 191 /** 192 * Creates a copy of the current message exchange so that it can be 193 * forwarded to another destination 194 */ 195 Exchange copy(); 196 197 /** 198 * Copies the data into this exchange from the given exchange 199 * 200 * @param source is the source from which headers and messages will be copied 201 */ 202 void copyFrom(Exchange source); 203 204 /** 205 * Returns the unit of work that this exchange belongs to; which may map to 206 * zero, one or more physical transactions 207 */ 208 UnitOfWork getUnitOfWork(); 209 210 /** 211 * Sets the unit of work that this exchange belongs to; which may map to 212 * zero, one or more physical transactions 213 */ 214 void setUnitOfWork(UnitOfWork unitOfWork); 215 216 /** 217 * Returns the exchange id 218 * 219 * @return the unique id of the exchange 220 */ 221 String getExchangeId(); 222 223 /** 224 * Set the exchange id 225 * 226 * @param id 227 */ 228 void setExchangeId(String id); 229 230 }