1 /*
2 * $Header: /home/cvs/jakarta-commons/httpclient/src/java/org/apache/commons/httpclient/ChunkedInputStream.java,v 1.16.2.1 2003/10/04 02:31:26 mbecke Exp $
3 * $Revision: 1.16.2.1 $
4 * $Date: 2003/10/04 02:31:26 $
5 *
6 * ====================================================================
7 *
8 * The Apache Software License, Version 1.1
9 *
10 * Copyright (c) 2002-2003 The Apache Software Foundation. All rights
11 * reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 *
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 *
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in
22 * the documentation and/or other materials provided with the
23 * distribution.
24 *
25 * 3. The end-user documentation included with the redistribution, if
26 * any, must include the following acknowlegement:
27 * "This product includes software developed by the
28 * Apache Software Foundation (http://www.apache.org/)."
29 * Alternately, this acknowlegement may appear in the software itself,
30 * if and wherever such third-party acknowlegements normally appear.
31 *
32 * 4. The names "The Jakarta Project", "Commons", and "Apache Software
33 * Foundation" must not be used to endorse or promote products derived
34 * from this software without prior written permission. For written
35 * permission, please contact apache@apache.org.
36 *
37 * 5. Products derived from this software may not be called "Apache"
38 * nor may "Apache" appear in their names without prior written
39 * permission of the Apache Group.
40 *
41 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
44 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
45 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
46 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
47 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
48 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
49 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
51 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * SUCH DAMAGE.
53 * ====================================================================
54 *
55 * This software consists of voluntary contributions made by many
56 * individuals on behalf of the Apache Software Foundation. For more
57 * information on the Apache Software Foundation, please see
58 * <http://www.apache.org/>.
59 *
60 * [Additional notices, if required by prior licensing conditions]
61 *
62 */
63
64 package org.apache.commons.httpclient;
65
66 import java.io.ByteArrayOutputStream;
67 import java.io.IOException;
68 import java.io.InputStream;
69
70
71 /***
72 * <p>Transparently coalesces chunks of a HTTP stream that uses
73 * Transfer-Encoding chunked.</p>
74 *
75 * <p>Note that this class NEVER closes the underlying stream, even when close
76 * gets called. Instead, it will read until the "end" of its chunking on close,
77 * which allows for the seamless invocation of subsequent HTTP 1.1 calls, while
78 * not requiring the client to remember to read the entire contents of the
79 * response.</p>
80 *
81 * @see ResponseInputStream
82 *
83 * @author Ortwin Gl�ck
84 * @author Sean C. Sullivan
85 * @author Martin Elwin
86 * @author Eric Johnson
87 * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
88 * @author Michael Becke
89 * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
90 *
91 * @since 2.0
92 *
93 */
94
95 public class ChunkedInputStream extends InputStream {
96 /*** The inputstream that we're wrapping */
97 private InputStream in;
98
99 /*** The chunk size */
100 private int chunkSize;
101
102 /*** The current position within the current chunk */
103 private int pos;
104
105 /*** True if we'are at the beginning of stream */
106 private boolean bof = true;
107
108 /*** True if we've reached the end of stream */
109 private boolean eof = false;
110
111 /*** True if this stream is closed */
112 private boolean closed = false;
113
114 /*** The method that this stream came from */
115 private HttpMethod method;
116
117 /***
118 *
119 *
120 * @param in must be non-null
121 * @param method must be non-null
122 *
123 * @throws IOException If an IO error occurs
124 */
125 public ChunkedInputStream(
126 final InputStream in, final HttpMethod method) throws IOException {
127
128 if (in == null) {
129 throw new IllegalArgumentException("InputStream parameter may not be null");
130 }
131 if (method == null) {
132 throw new IllegalArgumentException("HttpMethod parameter may not be null");
133 }
134 this.in = in;
135 this.method = method;
136 this.pos = 0;
137 }
138
139 /***
140 * <p> Returns all the data in a chunked stream in coalesced form. A chunk
141 * is followed by a CRLF. The method returns -1 as soon as a chunksize of 0
142 * is detected.</p>
143 *
144 * <p> Trailer headers are read automcatically at the end of the stream and
145 * can be obtained with the getResponseFooters() method.</p>
146 *
147 * @return -1 of the end of the stream has been reached or the next data
148 * byte
149 * @throws IOException If an IO problem occurs
150 *
151 * @see HttpMethod#getResponseFooters()
152 */
153 public int read() throws IOException {
154
155 if (closed) {
156 throw new IOException("Attempted read from closed stream.");
157 }
158 if (eof) {
159 return -1;
160 }
161 if (pos >= chunkSize) {
162 nextChunk();
163 if (eof) {
164 return -1;
165 }
166 }
167 pos++;
168 return in.read();
169 }
170
171 /***
172 * Read some bytes from the stream.
173 * @param b The byte array that will hold the contents from the stream.
174 * @param off The offset into the byte array at which bytes will start to be
175 * placed.
176 * @param len the maximum number of bytes that can be returned.
177 * @return The number of bytes returned or -1 if the end of stream has been
178 * reached.
179 * @see java.io.InputStream#read(byte[], int, int)
180 * @throws IOException if an IO problem occurs.
181 */
182 public int read (byte[] b, int off, int len) throws IOException {
183
184 if (closed) {
185 throw new IOException("Attempted read from closed stream.");
186 }
187
188 if (eof) {
189 return -1;
190 }
191 if (pos >= chunkSize) {
192 nextChunk();
193 if (eof) {
194 return -1;
195 }
196 }
197 len = Math.min(len, chunkSize - pos);
198 int count = in.read(b, off, len);
199 pos += count;
200 return count;
201 }
202
203 /***
204 * Read some bytes from the stream.
205 * @param b The byte array that will hold the contents from the stream.
206 * @return The number of bytes returned or -1 if the end of stream has been
207 * reached.
208 * @see java.io.InputStream#read(byte[])
209 * @throws IOException if an IO problem occurs.
210 */
211 public int read (byte[] b) throws IOException {
212 return read(b, 0, b.length);
213 }
214
215 /***
216 * Read the CRLF terminator.
217 * @throws IOException If an IO error occurs.
218 */
219 private void readCRLF() throws IOException {
220 int cr = in.read();
221 int lf = in.read();
222 if ((cr != '\r') || (lf != '\n')) {
223 throw new IOException(
224 "CRLF expected at end of chunk: " + cr + "/" + lf);
225 }
226 }
227
228
229 /***
230 * Read the next chunk.
231 * @throws IOException If an IO error occurs.
232 */
233 private void nextChunk() throws IOException {
234 if (!bof) {
235 readCRLF();
236 }
237 chunkSize = getChunkSizeFromInputStream(in);
238 bof = false;
239 pos = 0;
240 if (chunkSize == 0) {
241 eof = true;
242 parseTrailerHeaders();
243 }
244 }
245
246 /***
247 * Expects the stream to start with a chunksize in hex with optional
248 * comments after a semicolon. The line must end with a CRLF: "a3; some
249 * comment\r\n" Positions the stream at the start of the next line.
250 *
251 * @param in The new input stream.
252 *
253 * @return the chunk size as integer
254 *
255 * @throws IOException when the chunk size could not be parsed
256 */
257 private static int getChunkSizeFromInputStream(final InputStream in)
258 throws IOException {
259
260 ByteArrayOutputStream baos = new ByteArrayOutputStream();
261 // States: 0=normal, 1=\r was scanned, 2=inside quoted string, -1=end
262 int state = 0;
263 while (state != -1) {
264 int b = in.read();
265 if (b == -1) {
266 throw new IOException("chunked stream ended unexpectedly");
267 }
268 switch (state) {
269 case 0:
270 switch (b) {
271 case '\r':
272 state = 1;
273 break;
274 case '\"':
275 state = 2;
276 /* fall through */
277 default:
278 baos.write(b);
279 }
280 break;
281
282 case 1:
283 if (b == '\n') {
284 state = -1;
285 } else {
286 // this was not CRLF
287 throw new IOException("Protocol violation: Unexpected"
288 + " single newline character in chunk size");
289 }
290 break;
291
292 case 2:
293 switch (b) {
294 case '//':
295 b = in.read();
296 baos.write(b);
297 break;
298 case '\"':
299 state = 0;
300 /* fall through */
301 default:
302 baos.write(b);
303 }
304 break;
305 default: throw new RuntimeException("assertion failed");
306 }
307 }
308
309 //parse data
310 String dataString = HttpConstants.getString(baos.toByteArray());
311 int separator = dataString.indexOf(';');
312 dataString = (separator > 0)
313 ? dataString.substring(0, separator).trim()
314 : dataString.trim();
315
316 int result;
317 try {
318 result = Integer.parseInt(dataString.trim(), 16);
319 } catch (NumberFormatException e) {
320 throw new IOException ("Bad chunk size: " + dataString);
321 }
322 return result;
323 }
324
325 /***
326 * Reads and stores the Trailer headers.
327 * @throws IOException If an IO problem occurs
328 */
329 private void parseTrailerHeaders() throws IOException {
330 Header[] footers = HttpParser.parseHeaders(in);
331
332 for (int i = 0; i < footers.length; i++) {
333 method.addResponseFooter(footers[i]);
334 }
335 }
336
337 /***
338 * Upon close, this reads the remainder of the chunked message,
339 * leaving the underlying socket at a position to start reading the
340 * next response without scanning.
341 * @throws IOException If an IO problem occurs.
342 */
343 public void close() throws IOException {
344 if (!closed) {
345 try {
346 if (!eof) {
347 exhaustInputStream(this);
348 }
349 } finally {
350 eof = true;
351 closed = true;
352 }
353 }
354 }
355
356 /***
357 * Exhaust an input stream, reading until EOF has been encountered.
358 *
359 * <p>Note that this function is intended as a non-public utility.
360 * This is a little weird, but it seemed silly to make a utility
361 * class for this one function, so instead it is just static and
362 * shared that way.</p>
363 *
364 * @param inStream The {@link InputStream} to exhaust.
365 * @throws IOException If an IO problem occurs
366 */
367 static void exhaustInputStream(InputStream inStream) throws IOException {
368 // read and discard the remainder of the message
369 byte buffer[] = new byte[1024];
370 while (inStream.read(buffer) >= 0) {
371 ;
372 }
373 }
374 }
This page was automatically generated by Maven