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.activemq.transport.stomp;
018
019 import java.io.DataInput;
020 import java.io.DataInputStream;
021 import java.io.DataOutput;
022 import java.io.DataOutputStream;
023 import java.io.IOException;
024 import java.util.HashMap;
025 import java.util.Iterator;
026 import java.util.Map;
027
028 import org.apache.activemq.util.ByteArrayInputStream;
029 import org.apache.activemq.util.ByteArrayOutputStream;
030 import org.apache.activemq.util.ByteSequence;
031 import org.apache.activemq.wireformat.WireFormat;
032
033 /**
034 * Implements marshalling and unmarsalling the <a
035 * href="http://stomp.codehaus.org/">Stomp</a> protocol.
036 */
037 public class StompWireFormat implements WireFormat {
038
039 private static final byte[] NO_DATA = new byte[] {};
040 private static final byte[] END_OF_FRAME = new byte[] {0, '\n'};
041
042 private static final int MAX_COMMAND_LENGTH = 1024;
043 private static final int MAX_HEADER_LENGTH = 1024 * 10;
044 private static final int MAX_HEADERS = 1000;
045 private static final int MAX_DATA_LENGTH = 1024 * 1024 * 100;
046
047 private int version = 1;
048
049 public ByteSequence marshal(Object command) throws IOException {
050 ByteArrayOutputStream baos = new ByteArrayOutputStream();
051 DataOutputStream dos = new DataOutputStream(baos);
052 marshal(command, dos);
053 dos.close();
054 return baos.toByteSequence();
055 }
056
057 public Object unmarshal(ByteSequence packet) throws IOException {
058 ByteArrayInputStream stream = new ByteArrayInputStream(packet);
059 DataInputStream dis = new DataInputStream(stream);
060 return unmarshal(dis);
061 }
062
063 public void marshal(Object command, DataOutput os) throws IOException {
064 StompFrame stomp = (org.apache.activemq.transport.stomp.StompFrame)command;
065
066 StringBuffer buffer = new StringBuffer();
067 buffer.append(stomp.getAction());
068 buffer.append(Stomp.NEWLINE);
069
070 // Output the headers.
071 for (Iterator iter = stomp.getHeaders().entrySet().iterator(); iter.hasNext();) {
072 Map.Entry entry = (Map.Entry)iter.next();
073 buffer.append(entry.getKey());
074 buffer.append(Stomp.Headers.SEPERATOR);
075 buffer.append(entry.getValue());
076 buffer.append(Stomp.NEWLINE);
077 }
078
079 // Add a newline to seperate the headers from the content.
080 buffer.append(Stomp.NEWLINE);
081
082 os.write(buffer.toString().getBytes("UTF-8"));
083 os.write(stomp.getContent());
084 os.write(END_OF_FRAME);
085 }
086
087 public Object unmarshal(DataInput in) throws IOException {
088
089 try {
090
091 // parse action
092 String action = parseAction(in);
093
094 // Parse the headers
095 HashMap<String, String> headers = parseHeaders(in);
096
097 // Read in the data part.
098 byte[] data = NO_DATA;
099 String contentLength = headers.get(Stomp.Headers.CONTENT_LENGTH);
100 if (contentLength != null) {
101
102 // Bless the client, he's telling us how much data to read in.
103 int length = parseContentLength(contentLength);
104
105 data = new byte[length];
106 in.readFully(data);
107
108 if (in.readByte() != 0) {
109 throw new ProtocolException(Stomp.Headers.CONTENT_LENGTH + " bytes were read and " + "there was no trailing null byte", true);
110 }
111
112 } else {
113
114 // We don't know how much to read.. data ends when we hit a 0
115 byte b;
116 ByteArrayOutputStream baos = null;
117 while ((b = in.readByte()) != 0) {
118
119 if (baos == null) {
120 baos = new ByteArrayOutputStream();
121 } else if (baos.size() > MAX_DATA_LENGTH) {
122 throw new ProtocolException("The maximum data length was exceeded", true);
123 }
124
125 baos.write(b);
126 }
127
128 if (baos != null) {
129 baos.close();
130 data = baos.toByteArray();
131 }
132
133 }
134
135 return new StompFrame(action, headers, data);
136
137 } catch (ProtocolException e) {
138 return new StompFrameError(e);
139 }
140
141 }
142
143 private String readLine(DataInput in, int maxLength, String errorMessage) throws IOException {
144 byte b;
145 ByteArrayOutputStream baos = new ByteArrayOutputStream(maxLength);
146 while ((b = in.readByte()) != '\n') {
147 if (baos.size() > maxLength) {
148 throw new ProtocolException(errorMessage, true);
149 }
150 baos.write(b);
151 }
152 baos.close();
153 ByteSequence sequence = baos.toByteSequence();
154 return new String(sequence.getData(), sequence.getOffset(), sequence.getLength(), "UTF-8");
155 }
156
157 protected String parseAction(DataInput in) throws IOException {
158 String action = null;
159
160 // skip white space to next real action line
161 while (true) {
162 action = readLine(in, MAX_COMMAND_LENGTH, "The maximum command length was exceeded");
163 if (action == null) {
164 throw new IOException("connection was closed");
165 } else {
166 action = action.trim();
167 if (action.length() > 0) {
168 break;
169 }
170 }
171 }
172 return action;
173 }
174
175 protected HashMap<String, String> parseHeaders(DataInput in) throws IOException {
176 HashMap<String, String> headers = new HashMap<String, String>(25);
177 while (true) {
178 String line = readLine(in, MAX_HEADER_LENGTH, "The maximum header length was exceeded");
179 if (line != null && line.trim().length() > 0) {
180
181 if (headers.size() > MAX_HEADERS) {
182 throw new ProtocolException("The maximum number of headers was exceeded", true);
183 }
184
185 try {
186 int seperatorIndex = line.indexOf(Stomp.Headers.SEPERATOR);
187 String name = line.substring(0, seperatorIndex).trim();
188 String value = line.substring(seperatorIndex + 1, line.length()).trim();
189 headers.put(name, value);
190 } catch (Exception e) {
191 throw new ProtocolException("Unable to parser header line [" + line + "]", true);
192 }
193 } else {
194 break;
195 }
196 }
197 return headers;
198 }
199
200 protected int parseContentLength(String contentLength) throws ProtocolException {
201 int length;
202 try {
203 length = Integer.parseInt(contentLength.trim());
204 } catch (NumberFormatException e) {
205 throw new ProtocolException("Specified content-length is not a valid integer", true);
206 }
207
208 if (length > MAX_DATA_LENGTH) {
209 throw new ProtocolException("The maximum data length was exceeded", true);
210 }
211
212 return length;
213 }
214
215 public int getVersion() {
216 return version;
217 }
218
219 public void setVersion(int version) {
220 this.version = version;
221 }
222
223 }