001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied. See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019
020 package javax.servlet.http;
021
022 import java.io.IOException;
023
024 import javax.servlet.ServletResponse;
025
026 /**
027 *
028 * Extends the {@link ServletResponse} interface to provide HTTP-specific
029 * functionality in sending a response. For example, it has methods
030 * to access HTTP headers and cookies.
031 *
032 * <p>The servlet container creates an <code>HttpServletResponse</code> object
033 * and passes it as an argument to the servlet's service methods
034 * (<code>doGet</code>, <code>doPost</code>, etc).
035 *
036 *
037 * @author Various
038 * @version $Version$
039 *
040 * @see javax.servlet.ServletResponse
041 *
042 */
043
044
045
046 public interface HttpServletResponse extends ServletResponse {
047
048 /**
049 * Adds the specified cookie to the response. This method can be called
050 * multiple times to set more than one cookie.
051 *
052 * @param cookie the Cookie to return to the client
053 *
054 */
055
056 public void addCookie(Cookie cookie);
057
058 /**
059 * Returns a boolean indicating whether the named response header
060 * has already been set.
061 *
062 * @param name the header name
063 * @return <code>true</code> if the named response header
064 * has already been set;
065 * <code>false</code> otherwise
066 */
067
068 public boolean containsHeader(String name);
069
070 /**
071 * Encodes the specified URL by including the session ID in it,
072 * or, if encoding is not needed, returns the URL unchanged.
073 * The implementation of this method includes the logic to
074 * determine whether the session ID needs to be encoded in the URL.
075 * For example, if the browser supports cookies, or session
076 * tracking is turned off, URL encoding is unnecessary.
077 *
078 * <p>For robust session tracking, all URLs emitted by a servlet
079 * should be run through this
080 * method. Otherwise, URL rewriting cannot be used with browsers
081 * which do not support cookies.
082 *
083 * @param url the url to be encoded.
084 * @return the encoded URL if encoding is needed;
085 * the unchanged URL otherwise.
086 */
087
088 public String encodeURL(String url);
089
090 /**
091 * Encodes the specified URL for use in the
092 * <code>sendRedirect</code> method or, if encoding is not needed,
093 * returns the URL unchanged. The implementation of this method
094 * includes the logic to determine whether the session ID
095 * needs to be encoded in the URL. Because the rules for making
096 * this determination can differ from those used to decide whether to
097 * encode a normal link, this method is separated from the
098 * <code>encodeURL</code> method.
099 *
100 * <p>All URLs sent to the <code>HttpServletResponse.sendRedirect</code>
101 * method should be run through this method. Otherwise, URL
102 * rewriting cannot be used with browsers which do not support
103 * cookies.
104 *
105 * @param url the url to be encoded.
106 * @return the encoded URL if encoding is needed;
107 * the unchanged URL otherwise.
108 *
109 * @see #sendRedirect
110 * @see #encodeUrl
111 */
112
113 public String encodeRedirectURL(String url);
114
115 /**
116 * @deprecated As of version 2.1, use encodeURL(String url) instead
117 *
118 * @param url the url to be encoded.
119 * @return the encoded URL if encoding is needed;
120 * the unchanged URL otherwise.
121 */
122
123 public String encodeUrl(String url);
124
125 /**
126 * @deprecated As of version 2.1, use
127 * encodeRedirectURL(String url) instead
128 *
129 * @param url the url to be encoded.
130 * @return the encoded URL if encoding is needed;
131 * the unchanged URL otherwise.
132 */
133
134 public String encodeRedirectUrl(String url);
135
136 /**
137 * Sends an error response to the client using the specified
138 * status. The server defaults to creating the
139 * response to look like an HTML-formatted server error page
140 * containing the specified message, setting the content type
141 * to "text/html", leaving cookies and other headers unmodified.
142 *
143 * If an error-page declaration has been made for the web application
144 * corresponding to the status code passed in, it will be served back in
145 * preference to the suggested msg parameter.
146 *
147 * <p>If the response has already been committed, this method throws
148 * an IllegalStateException.
149 * After using this method, the response should be considered
150 * to be committed and should not be written to.
151 *
152 * @param sc the error status code
153 * @param msg the descriptive message
154 * @exception IOException If an input or output exception occurs
155 * @exception IllegalStateException If the response was committed
156 */
157
158 public void sendError(int sc, String msg) throws IOException;
159
160 /**
161 * Sends an error response to the client using the specified status
162 * code and clearing the buffer.
163 * <p>If the response has already been committed, this method throws
164 * an IllegalStateException.
165 * After using this method, the response should be considered
166 * to be committed and should not be written to.
167 *
168 * @param sc the error status code
169 * @exception IOException If an input or output exception occurs
170 * @exception IllegalStateException If the response was committed
171 * before this method call
172 */
173
174 public void sendError(int sc) throws IOException;
175
176 /**
177 * Sends a temporary redirect response to the client using the
178 * specified redirect location URL. This method can accept relative URLs;
179 * the servlet container must convert the relative URL to an absolute URL
180 * before sending the response to the client. If the location is relative
181 * without a leading '/' the container interprets it as relative to
182 * the current request URI. If the location is relative with a leading
183 * '/' the container interprets it as relative to the servlet container root.
184 *
185 * <p>If the response has already been committed, this method throws
186 * an IllegalStateException.
187 * After using this method, the response should be considered
188 * to be committed and should not be written to.
189 *
190 * @param location the redirect location URL
191 * @exception IOException If an input or output exception occurs
192 * @exception IllegalStateException If the response was committed or
193 if a partial URL is given and cannot be converted into a valid URL
194 */
195
196 public void sendRedirect(String location) throws IOException;
197
198 /**
199 *
200 * Sets a response header with the given name and
201 * date-value. The date is specified in terms of
202 * milliseconds since the epoch. If the header had already
203 * been set, the new value overwrites the previous one. The
204 * <code>containsHeader</code> method can be used to test for the
205 * presence of a header before setting its value.
206 *
207 * @param name the name of the header to set
208 * @param date the assigned date value
209 *
210 * @see #containsHeader
211 * @see #addDateHeader
212 */
213
214 public void setDateHeader(String name, long date);
215
216 /**
217 *
218 * Adds a response header with the given name and
219 * date-value. The date is specified in terms of
220 * milliseconds since the epoch. This method allows response headers
221 * to have multiple values.
222 *
223 * @param name the name of the header to set
224 * @param date the additional date value
225 *
226 * @see #setDateHeader
227 */
228
229 public void addDateHeader(String name, long date);
230
231 /**
232 *
233 * Sets a response header with the given name and value.
234 * If the header had already been set, the new value overwrites the
235 * previous one. The <code>containsHeader</code> method can be
236 * used to test for the presence of a header before setting its
237 * value.
238 *
239 * @param name the name of the header
240 * @param value the header value If it contains octet string,
241 * it should be encoded according to RFC 2047
242 * (http://www.ietf.org/rfc/rfc2047.txt)
243 *
244 * @see #containsHeader
245 * @see #addHeader
246 */
247
248 public void setHeader(String name, String value);
249
250 /**
251 * Adds a response header with the given name and value.
252 * This method allows response headers to have multiple values.
253 *
254 * @param name the name of the header
255 * @param value the additional header value If it contains
256 * octet string, it should be encoded
257 * according to RFC 2047
258 * (http://www.ietf.org/rfc/rfc2047.txt)
259 *
260 * @see #setHeader
261 */
262
263 public void addHeader(String name, String value);
264
265 /**
266 * Sets a response header with the given name and
267 * integer value. If the header had already been set, the new value
268 * overwrites the previous one. The <code>containsHeader</code>
269 * method can be used to test for the presence of a header before
270 * setting its value.
271 *
272 * @param name the name of the header
273 * @param value the assigned integer value
274 *
275 * @see #containsHeader
276 * @see #addIntHeader
277 */
278
279 public void setIntHeader(String name, int value);
280
281 /**
282 * Adds a response header with the given name and
283 * integer value. This method allows response headers to have multiple
284 * values.
285 *
286 * @param name the name of the header
287 * @param value the assigned integer value
288 *
289 * @see #setIntHeader
290 */
291
292 public void addIntHeader(String name, int value);
293
294
295
296 /**
297 * Sets the status code for this response. This method is used to
298 * set the return status code when there is no error (for example,
299 * for the status codes SC_OK or SC_MOVED_TEMPORARILY). If there
300 * is an error, and the caller wishes to invoke an error-page defined
301 * in the web application, the <code>sendError</code> method should be used
302 * instead.
303 * <p> The container clears the buffer and sets the Location header, preserving
304 * cookies and other headers.
305 *
306 * @param sc the status code
307 *
308 * @see #sendError
309 */
310
311 public void setStatus(int sc);
312
313 /**
314 * @deprecated As of version 2.1, due to ambiguous meaning of the
315 * message parameter. To set a status code
316 * use <code>setStatus(int)</code>, to send an error with a description
317 * use <code>sendError(int, String)</code>.
318 *
319 * Sets the status code and message for this response.
320 *
321 * @param sc the status code
322 * @param sm the status message
323 */
324
325 public void setStatus(int sc, String sm);
326
327
328 /*
329 * Server status codes; see RFC 2068.
330 */
331
332 /**
333 * Status code (100) indicating the client can continue.
334 */
335
336 public static final int SC_CONTINUE = 100;
337
338
339 /**
340 * Status code (101) indicating the server is switching protocols
341 * according to Upgrade header.
342 */
343
344 public static final int SC_SWITCHING_PROTOCOLS = 101;
345
346 /**
347 * Status code (200) indicating the request succeeded normally.
348 */
349
350 public static final int SC_OK = 200;
351
352 /**
353 * Status code (201) indicating the request succeeded and created
354 * a new resource on the server.
355 */
356
357 public static final int SC_CREATED = 201;
358
359 /**
360 * Status code (202) indicating that a request was accepted for
361 * processing, but was not completed.
362 */
363
364 public static final int SC_ACCEPTED = 202;
365
366 /**
367 * Status code (203) indicating that the meta information presented
368 * by the client did not originate from the server.
369 */
370
371 public static final int SC_NON_AUTHORITATIVE_INFORMATION = 203;
372
373 /**
374 * Status code (204) indicating that the request succeeded but that
375 * there was no new information to return.
376 */
377
378 public static final int SC_NO_CONTENT = 204;
379
380 /**
381 * Status code (205) indicating that the agent <em>SHOULD</em> reset
382 * the document view which caused the request to be sent.
383 */
384
385 public static final int SC_RESET_CONTENT = 205;
386
387 /**
388 * Status code (206) indicating that the server has fulfilled
389 * the partial GET request for the resource.
390 */
391
392 public static final int SC_PARTIAL_CONTENT = 206;
393
394 /**
395 * Status code (300) indicating that the requested resource
396 * corresponds to any one of a set of representations, each with
397 * its own specific location.
398 */
399
400 public static final int SC_MULTIPLE_CHOICES = 300;
401
402 /**
403 * Status code (301) indicating that the resource has permanently
404 * moved to a new location, and that future references should use a
405 * new URI with their requests.
406 */
407
408 public static final int SC_MOVED_PERMANENTLY = 301;
409
410 /**
411 * Status code (302) indicating that the resource has temporarily
412 * moved to another location, but that future references should
413 * still use the original URI to access the resource.
414 *
415 * This definition is being retained for backwards compatibility.
416 * SC_FOUND is now the preferred definition.
417 */
418
419 public static final int SC_MOVED_TEMPORARILY = 302;
420
421 /**
422 * Status code (302) indicating that the resource reside
423 * temporarily under a different URI. Since the redirection might
424 * be altered on occasion, the client should continue to use the
425 * Request-URI for future requests.(HTTP/1.1) To represent the
426 * status code (302), it is recommended to use this variable.
427 */
428
429 public static final int SC_FOUND = 302;
430
431 /**
432 * Status code (303) indicating that the response to the request
433 * can be found under a different URI.
434 */
435
436 public static final int SC_SEE_OTHER = 303;
437
438 /**
439 * Status code (304) indicating that a conditional GET operation
440 * found that the resource was available and not modified.
441 */
442
443 public static final int SC_NOT_MODIFIED = 304;
444
445 /**
446 * Status code (305) indicating that the requested resource
447 * <em>MUST</em> be accessed through the proxy given by the
448 * <code><em>Location</em></code> field.
449 */
450
451 public static final int SC_USE_PROXY = 305;
452
453 /**
454 * Status code (307) indicating that the requested resource
455 * resides temporarily under a different URI. The temporary URI
456 * <em>SHOULD</em> be given by the <code><em>Location</em></code>
457 * field in the response.
458 */
459
460 public static final int SC_TEMPORARY_REDIRECT = 307;
461
462 /**
463 * Status code (400) indicating the request sent by the client was
464 * syntactically incorrect.
465 */
466
467 public static final int SC_BAD_REQUEST = 400;
468
469 /**
470 * Status code (401) indicating that the request requires HTTP
471 * authentication.
472 */
473
474 public static final int SC_UNAUTHORIZED = 401;
475
476 /**
477 * Status code (402) reserved for future use.
478 */
479
480 public static final int SC_PAYMENT_REQUIRED = 402;
481
482 /**
483 * Status code (403) indicating the server understood the request
484 * but refused to fulfill it.
485 */
486
487 public static final int SC_FORBIDDEN = 403;
488
489 /**
490 * Status code (404) indicating that the requested resource is not
491 * available.
492 */
493
494 public static final int SC_NOT_FOUND = 404;
495
496 /**
497 * Status code (405) indicating that the method specified in the
498 * <code><em>Request-Line</em></code> is not allowed for the resource
499 * identified by the <code><em>Request-URI</em></code>.
500 */
501
502 public static final int SC_METHOD_NOT_ALLOWED = 405;
503
504 /**
505 * Status code (406) indicating that the resource identified by the
506 * request is only capable of generating response entities which have
507 * content characteristics not acceptable according to the accept
508 * headers sent in the request.
509 */
510
511 public static final int SC_NOT_ACCEPTABLE = 406;
512
513 /**
514 * Status code (407) indicating that the client <em>MUST</em> first
515 * authenticate itself with the proxy.
516 */
517
518 public static final int SC_PROXY_AUTHENTICATION_REQUIRED = 407;
519
520 /**
521 * Status code (408) indicating that the client did not produce a
522 * request within the time that the server was prepared to wait.
523 */
524
525 public static final int SC_REQUEST_TIMEOUT = 408;
526
527 /**
528 * Status code (409) indicating that the request could not be
529 * completed due to a conflict with the current state of the
530 * resource.
531 */
532
533 public static final int SC_CONFLICT = 409;
534
535 /**
536 * Status code (410) indicating that the resource is no longer
537 * available at the server and no forwarding address is known.
538 * This condition <em>SHOULD</em> be considered permanent.
539 */
540
541 public static final int SC_GONE = 410;
542
543 /**
544 * Status code (411) indicating that the request cannot be handled
545 * without a defined <code><em>Content-Length</em></code>.
546 */
547
548 public static final int SC_LENGTH_REQUIRED = 411;
549
550 /**
551 * Status code (412) indicating that the precondition given in one
552 * or more of the request-header fields evaluated to false when it
553 * was tested on the server.
554 */
555
556 public static final int SC_PRECONDITION_FAILED = 412;
557
558 /**
559 * Status code (413) indicating that the server is refusing to process
560 * the request because the request entity is larger than the server is
561 * willing or able to process.
562 */
563
564 public static final int SC_REQUEST_ENTITY_TOO_LARGE = 413;
565
566 /**
567 * Status code (414) indicating that the server is refusing to service
568 * the request because the <code><em>Request-URI</em></code> is longer
569 * than the server is willing to interpret.
570 */
571
572 public static final int SC_REQUEST_URI_TOO_LONG = 414;
573
574 /**
575 * Status code (415) indicating that the server is refusing to service
576 * the request because the entity of the request is in a format not
577 * supported by the requested resource for the requested method.
578 */
579
580 public static final int SC_UNSUPPORTED_MEDIA_TYPE = 415;
581
582 /**
583 * Status code (416) indicating that the server cannot serve the
584 * requested byte range.
585 */
586
587 public static final int SC_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
588
589 /**
590 * Status code (417) indicating that the server could not meet the
591 * expectation given in the Expect request header.
592 */
593
594 public static final int SC_EXPECTATION_FAILED = 417;
595
596 /**
597 * Status code (500) indicating an error inside the HTTP server
598 * which prevented it from fulfilling the request.
599 */
600
601 public static final int SC_INTERNAL_SERVER_ERROR = 500;
602
603 /**
604 * Status code (501) indicating the HTTP server does not support
605 * the functionality needed to fulfill the request.
606 */
607
608 public static final int SC_NOT_IMPLEMENTED = 501;
609
610 /**
611 * Status code (502) indicating that the HTTP server received an
612 * invalid response from a server it consulted when acting as a
613 * proxy or gateway.
614 */
615
616 public static final int SC_BAD_GATEWAY = 502;
617
618 /**
619 * Status code (503) indicating that the HTTP server is
620 * temporarily overloaded, and unable to handle the request.
621 */
622
623 public static final int SC_SERVICE_UNAVAILABLE = 503;
624
625 /**
626 * Status code (504) indicating that the server did not receive
627 * a timely response from the upstream server while acting as
628 * a gateway or proxy.
629 */
630
631 public static final int SC_GATEWAY_TIMEOUT = 504;
632
633 /**
634 * Status code (505) indicating that the server does not support
635 * or refuses to support the HTTP protocol version that was used
636 * in the request message.
637 */
638
639 public static final int SC_HTTP_VERSION_NOT_SUPPORTED = 505;
640 }