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: 36635 $ 030 */ 031 public interface Exchange { 032 033 /** 034 * Returns the {@link ExchangePattern} (MEP) of this exchange. 035 * 036 * @return the message exchange pattern of this exchange 037 */ 038 ExchangePattern getPattern(); 039 040 /** 041 * Returns a property associated with this exchange by name 042 * 043 * @param name the name of the property 044 * @return the value of the given header or null if there is no property for 045 * the given name 046 */ 047 Object getProperty(String name); 048 049 /** 050 * Returns a property associated with this exchange by name and specifying 051 * the type required 052 * 053 * @param name the name of the property 054 * @param type the type of the property 055 * @return the value of the given header or null if there is no property for 056 * the given name or null if it cannot be converted to the given 057 * type 058 */ 059 <T> T getProperty(String name, Class<T> type); 060 061 /** 062 * Sets a property on the exchange 063 * 064 * @param name of the property 065 * @param value to associate with the name 066 */ 067 void setProperty(String name, Object value); 068 069 /** 070 * Removes the given property on the exchange 071 * 072 * @param name of the property 073 * @return the old value of the property 074 */ 075 Object removeProperty(String name); 076 077 /** 078 * Returns all of the properties associated with the exchange 079 * 080 * @return all the headers in a Map 081 */ 082 Map<String, Object> getProperties(); 083 084 /** 085 * Returns the inbound request message 086 * 087 * @return the message 088 */ 089 Message getIn(); 090 091 /** 092 * Sets the inbound message instance 093 * 094 * @param in the inbound message 095 */ 096 void setIn(Message in); 097 098 /** 099 * Returns the outbound message, lazily creating one if one has not already 100 * been associated with this exchange. If you want to inspect this property 101 * but not force lazy creation then invoke the {@link #getOut(boolean)} 102 * method passing in <tt>false</tt> 103 * 104 * @return the response 105 */ 106 Message getOut(); 107 108 /** 109 * Returns the outbound message; optionally lazily creating one if one has 110 * not been associated with this exchange 111 * 112 * @return the response 113 */ 114 Message getOut(boolean lazyCreate); 115 116 /** 117 * Sets the outbound message 118 * 119 * @param out the outbound message 120 */ 121 void setOut(Message out); 122 123 /** 124 * Returns the fault message 125 * 126 * @return the fault 127 */ 128 Message getFault(); 129 130 /** 131 * Returns the fault message; optionally lazily creating one if one has 132 * not been associated with this exchange 133 * 134 * @param lazyCreate <tt>true</tt> will lazy create the fault message 135 * 136 * @return the fault 137 */ 138 Message getFault(boolean lazyCreate); 139 140 /** 141 * Returns the exception associated with this exchange 142 * 143 * @return the exception (or null if no faults) 144 */ 145 Throwable getException(); 146 147 /** 148 * Sets the exception associated with this exchange 149 * 150 * @param e the caused exception 151 */ 152 void setException(Throwable e); 153 154 /** 155 * Returns true if this exchange failed due to either an exception or fault 156 * 157 * @return true if this exchange failed due to either an exception or fault 158 * @see Exchange#getException() 159 * @see Exchange#getFault() 160 */ 161 boolean isFailed(); 162 163 /** 164 * Returns the container so that a processor can resolve endpoints from URIs 165 * 166 * @return the container which owns this exchange 167 */ 168 CamelContext getContext(); 169 170 /** 171 * Creates a new exchange instance with empty messages, headers and properties 172 */ 173 Exchange newInstance(); 174 175 /** 176 * Creates a copy of the current message exchange so that it can be 177 * forwarded to another destination 178 */ 179 Exchange copy(); 180 181 /** 182 * Copies the data into this exchange from the given exchange 183 * 184 * @param source is the source from which headers and messages will be copied 185 */ 186 void copyFrom(Exchange source); 187 188 /** 189 * Returns the unit of work that this exchange belongs to; which may map to 190 * zero, one or more physical transactions 191 */ 192 UnitOfWork getUnitOfWork(); 193 194 /** 195 * Sets the unit of work that this exchange belongs to; which may map to 196 * zero, one or more physical transactions 197 */ 198 void setUnitOfWork(UnitOfWork unitOfWork); 199 200 /** 201 * Returns the exchange id 202 * 203 * @return the unique id of the exchange 204 */ 205 String getExchangeId(); 206 207 /** 208 * Set the exchange id 209 * 210 * @param id 211 */ 212 void setExchangeId(String id); 213 }