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 import java.util.Set;
021
022 import javax.activation.DataHandler;
023
024 /**
025 * Implements the <a
026 * href="http://camel.apache.org/message.html">Message</a> pattern and
027 * represents an inbound or outbound message as part of an {@link Exchange}
028 *
029 * @version $Revision: 746974 $
030 */
031 public interface Message {
032
033 /**
034 * Returns the id of the message
035 */
036 String getMessageId();
037
038 /**
039 * Sets the id of the message
040 *
041 * @param messageId id of the message
042 */
043 void setMessageId(String messageId);
044
045 /**
046 * Returns the exchange this message is related to
047 */
048 Exchange getExchange();
049
050 /**
051 * Accesses a specific header
052 *
053 * @param name name of header
054 * @return object header associated with the name
055 */
056 Object getHeader(String name);
057
058 /**
059 * Returns a header associated with this message by name and specifying the
060 * type required
061 *
062 * @param name the name of the header
063 * @param type the type of the header
064 * @return the value of the given header or null if there is no property for
065 * the given name or it cannot be converted to the given type
066 */
067 <T> T getHeader(String name, Class<T> type);
068
069 /**
070 * Sets a header on the message
071 *
072 * @param name of the header
073 * @param value to associate with the name
074 */
075 void setHeader(String name, Object value);
076
077 /**
078 * Removes the named header from this message
079 *
080 * @param name name of the header
081 * @return the old value of the header
082 */
083 Object removeHeader(String name);
084
085 /**
086 * Returns all of the headers associated with the message
087 *
088 * @return all the headers in a Map
089 */
090 Map<String, Object> getHeaders();
091
092 /**
093 * Set all the headers associated with this message
094 *
095 * @param headers headers to set
096 */
097 void setHeaders(Map<String, Object> headers);
098
099 /**
100 * Returns the body of the message as a POJO
101 */
102 Object getBody();
103
104 /**
105 * Returns the body as the specified type
106 *
107 * @param type the type that the body
108 * @return the body of the message as the specified type
109 */
110 <T> T getBody(Class<T> type);
111
112 /**
113 * Sets the body of the message
114 *
115 * @param body the body
116 */
117 void setBody(Object body);
118
119 /**
120 * Sets the body of the message as a specific type
121 *
122 * @param body the body
123 * @param type the type of the body
124 */
125 <T> void setBody(Object body, Class<T> type);
126
127 /**
128 * Creates a copy of this message so that it can be used and possibly
129 * modified further in another exchange
130 *
131 * @return a new message instance copied from this message
132 */
133 Message copy();
134
135 /**
136 * Copies the contents of the other message into this message
137 *
138 * @param message the other message
139 */
140 void copyFrom(Message message);
141
142 /**
143 * Returns the attachment specified by the id
144 *
145 * @param id the id under which the attachment is stored
146 * @return the data handler for this attachment or null
147 */
148 DataHandler getAttachment(String id);
149
150 /**
151 * Returns a set of attachment names of the message
152 *
153 * @return a set of attachment names
154 */
155 Set<String> getAttachmentNames();
156
157 /**
158 * Removes the attachment specified by the id
159 *
160 * @param id the id of the attachment to remove
161 */
162 void removeAttachment(String id);
163
164 /**
165 * Adds an attachment to the message using the id
166 *
167 * @param id the id to store the attachment under
168 * @param content the data handler for the attachment
169 */
170 void addAttachment(String id, DataHandler content);
171
172 /**
173 * Returns all attachments of the message
174 *
175 * @return the attachments in a map or null
176 */
177 Map<String, DataHandler> getAttachments();
178
179 /**
180 * Set all the attachments associated with this message
181 *
182 * @param attachments attachements
183 */
184 void setAttachments(Map<String, DataHandler> attachments);
185
186 /**
187 * Returns <tt>true</tt> if this message has any attachments.
188 */
189 boolean hasAttachments();
190
191 /**
192 * Returns the unique ID for a message exchange if this message is capable of creating one or null if not
193 */
194 String createExchangeId();
195 }