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.impl;
018
019 import java.util.HashMap;
020 import java.util.Map;
021 import java.util.Set;
022
023 import javax.activation.DataHandler;
024
025 import org.apache.camel.Message;
026
027 /**
028 * The default implementation of {@link Message}
029 *
030 * @version $Revision: 653092 $
031 */
032 public class DefaultMessage extends MessageSupport {
033 private Map<String, Object> headers;
034 private Map<String, DataHandler> attachments;
035
036 @Override
037 public String toString() {
038 return "Message: " + getBody();
039 }
040
041 public Object getHeader(String name) {
042 return getHeaders().get(name);
043 }
044
045 public <T> T getHeader(String name, Class<T> type) {
046 Object value = getHeader(name);
047 return getExchange().getContext().getTypeConverter().convertTo(type, value);
048 }
049
050 public void setHeader(String name, Object value) {
051 if (headers == null) {
052 headers = createHeaders();
053 }
054 headers.put(name, value);
055 }
056
057 public Object removeHeader(String name) {
058 if (headers != null) {
059 return headers.remove(name);
060 } else {
061 return null;
062 }
063 }
064
065 public Map<String, Object> getHeaders() {
066 if (headers == null) {
067 headers = createHeaders();
068 }
069 return headers;
070 }
071
072 public void setHeaders(Map<String, Object> headers) {
073 this.headers = headers;
074 }
075
076 public DefaultMessage newInstance() {
077 return new DefaultMessage();
078 }
079
080 /**
081 * A factory method to lazily create the headers to make it easy to create
082 * efficient Message implementations which only construct and populate the
083 * Map on demand
084 *
085 * @return return a newly constructed Map possibly containing headers from
086 * the underlying inbound transport
087 */
088 protected Map<String, Object> createHeaders() {
089 HashMap<String, Object> map = new HashMap<String, Object>();
090 populateInitialHeaders(map);
091 return map;
092 }
093
094 /**
095 * A strategy method populate the initial set of headers on an inbound
096 * message from an underlying binding
097 *
098 * @param map is the empty header map to populate
099 */
100 protected void populateInitialHeaders(Map<String, Object> map) {
101 }
102
103 /**
104 * A factory method to lazily create the attachments to make it easy to
105 * create efficient Message implementations which only construct and
106 * populate the Map on demand
107 *
108 * @return return a newly constructed Map
109 */
110 protected Map<String, DataHandler> createAttachments() {
111 HashMap<String, DataHandler> map = new HashMap<String, DataHandler>();
112 populateInitialAttachments(map);
113 return map;
114 }
115
116 /**
117 * A strategy method populate the initial set of attachments on an inbound
118 * message from an underlying binding
119 *
120 * @param map is the empty attachment map to populate
121 */
122 protected void populateInitialAttachments(Map<String, DataHandler> map) {
123 }
124
125 public void addAttachment(String id, DataHandler content) {
126 if (attachments == null) {
127 attachments = createAttachments();
128 }
129 attachments.put(id, content);
130 }
131
132 public DataHandler getAttachment(String id) {
133 return getAttachments().get(id);
134 }
135
136 public Set<String> getAttachmentNames() {
137 if (attachments == null) {
138 attachments = createAttachments();
139 }
140 return attachments.keySet();
141 }
142
143 public void removeAttachment(String id) {
144 if (attachments != null && attachments.containsKey(id)) {
145 attachments.remove(id);
146 }
147 }
148
149 public Map<String, DataHandler> getAttachments() {
150 if (attachments == null) {
151 attachments = createAttachments();
152 }
153 return attachments;
154 }
155
156 public void setAttachments(Map<String, DataHandler> attachments) {
157 this.attachments = attachments;
158 }
159
160 public boolean hasAttachments() {
161 return this.attachments != null && this.attachments.size() > 0;
162 }
163
164 /**
165 * Returns true if the headers have been mutated in some way
166 */
167 protected boolean hasPopulatedHeaders() {
168 return headers != null;
169 }
170
171 }