001 /*
002 * Copyright 2004 The Apache Software Foundation
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016 package javax.servlet.http;
017
018 import java.io.IOException;
019
020 import javax.servlet.ServletResponse;
021
022 /**
023 *
024 * Extends the {@link ServletResponse} interface to provide HTTP-specific
025 * functionality in sending a response. For example, it has methods
026 * to access HTTP headers and cookies.
027 *
028 * <p>The servlet container creates an <code>HttpServletResponse</code> object
029 * and passes it as an argument to the servlet's service methods
030 * (<code>doGet</code>, <code>doPost</code>, etc).
031 *
032 *
033 * @author Various
034 * @version $Version$
035 *
036 * @see javax.servlet.ServletResponse
037 *
038 */
039
040 public interface HttpServletResponse extends ServletResponse {
041
042 /**
043 * Adds the specified cookie to the response. This method can be called
044 * multiple times to set more than one cookie.
045 *
046 * @param cookie the Cookie to return to the client
047 *
048 */
049
050 public void addCookie(Cookie cookie);
051
052 /**
053 * Returns a boolean indicating whether the named response header
054 * has already been set.
055 *
056 * @param name the header name
057 * @return <code>true</code> if the named response header
058 * has already been set;
059 * <code>false</code> otherwise
060 */
061
062 public boolean containsHeader(String name);
063
064 /**
065 * Encodes the specified URL by including the session ID in it,
066 * or, if encoding is not needed, returns the URL unchanged.
067 * The implementation of this method includes the logic to
068 * determine whether the session ID needs to be encoded in the URL.
069 * For example, if the browser supports cookies, or session
070 * tracking is turned off, URL encoding is unnecessary.
071 *
072 * <p>For robust session tracking, all URLs emitted by a servlet
073 * should be run through this
074 * method. Otherwise, URL rewriting cannot be used with browsers
075 * which do not support cookies.
076 *
077 * @param url the url to be encoded.
078 * @return the encoded URL if encoding is needed;
079 * the unchanged URL otherwise.
080 */
081
082 public String encodeURL(String url);
083
084 /**
085 * Encodes the specified URL for use in the
086 * <code>sendRedirect</code> method or, if encoding is not needed,
087 * returns the URL unchanged. The implementation of this method
088 * includes the logic to determine whether the session ID
089 * needs to be encoded in the URL. Because the rules for making
090 * this determination can differ from those used to decide whether to
091 * encode a normal link, this method is separated from the
092 * <code>encodeURL</code> method.
093 *
094 * <p>All URLs sent to the <code>HttpServletResponse.sendRedirect</code>
095 * method should be run through this method. Otherwise, URL
096 * rewriting cannot be used with browsers which do not support
097 * cookies.
098 *
099 * @param url the url to be encoded.
100 * @return the encoded URL if encoding is needed;
101 * the unchanged URL otherwise.
102 *
103 * @see #sendRedirect
104 * @see #encodeUrl
105 */
106
107 public String encodeRedirectURL(String url);
108
109 /**
110 * @deprecated As of version 2.1, use encodeURL(String url) instead
111 *
112 * @param url the url to be encoded.
113 * @return the encoded URL if encoding is needed;
114 * the unchanged URL otherwise.
115 */
116
117 public String encodeUrl(String url);
118
119 /**
120 * @deprecated As of version 2.1, use
121 * encodeRedirectURL(String url) instead
122 *
123 * @param url the url to be encoded.
124 * @return the encoded URL if encoding is needed;
125 * the unchanged URL otherwise.
126 */
127
128 public String encodeRedirectUrl(String url);
129
130 /**
131 * Sends an error response to the client using the specified
132 * status. The server defaults to creating the
133 * response to look like an HTML-formatted server error page
134 * containing the specified message, setting the content type
135 * to "text/html", leaving cookies and other headers unmodified.
136 *
137 * If an error-page declaration has been made for the web application
138 * corresponding to the status code passed in, it will be served back in
139 * preference to the suggested msg parameter.
140 *
141 * <p>If the response has already been committed, this method throws
142 * an IllegalStateException.
143 * After using this method, the response should be considered
144 * to be committed and should not be written to.
145 *
146 * @param sc the error status code
147 * @param msg the descriptive message
148 * @exception IOException If an input or output exception occurs
149 * @exception IllegalStateException If the response was committed
150 */
151
152 public void sendError(int sc, String msg) throws IOException;
153
154 /**
155 * Sends an error response to the client using the specified status
156 * code and clearing the buffer.
157 * <p>If the response has already been committed, this method throws
158 * an IllegalStateException.
159 * After using this method, the response should be considered
160 * to be committed and should not be written to.
161 *
162 * @param sc the error status code
163 * @exception IOException If an input or output exception occurs
164 * @exception IllegalStateException If the response was committed
165 * before this method call
166 */
167
168 public void sendError(int sc) throws IOException;
169
170 /**
171 * Sends a temporary redirect response to the client using the
172 * specified redirect location URL. This method can accept relative URLs;
173 * the servlet container must convert the relative URL to an absolute URL
174 * before sending the response to the client. If the location is relative
175 * without a leading '/' the container interprets it as relative to
176 * the current request URI. If the location is relative with a leading
177 * '/' the container interprets it as relative to the servlet container root.
178 *
179 * <p>If the response has already been committed, this method throws
180 * an IllegalStateException.
181 * After using this method, the response should be considered
182 * to be committed and should not be written to.
183 *
184 * @param location the redirect location URL
185 * @exception IOException If an input or output exception occurs
186 * @exception IllegalStateException If the response was committed or
187 if a partial URL is given and cannot be converted into a valid URL
188 */
189
190 public void sendRedirect(String location) throws IOException;
191
192 /**
193 *
194 * Sets a response header with the given name and
195 * date-value. The date is specified in terms of
196 * milliseconds since the epoch. If the header had already
197 * been set, the new value overwrites the previous one. The
198 * <code>containsHeader</code> method can be used to test for the
199 * presence of a header before setting its value.
200 *
201 * @param name the name of the header to set
202 * @param date the assigned date value
203 *
204 * @see #containsHeader
205 * @see #addDateHeader
206 */
207
208 public void setDateHeader(String name, long date);
209
210 /**
211 *
212 * Adds a response header with the given name and
213 * date-value. The date is specified in terms of
214 * milliseconds since the epoch. This method allows response headers
215 * to have multiple values.
216 *
217 * @param name the name of the header to set
218 * @param date the additional date value
219 *
220 * @see #setDateHeader
221 */
222
223 public void addDateHeader(String name, long date);
224
225 /**
226 *
227 * Sets a response header with the given name and value.
228 * If the header had already been set, the new value overwrites the
229 * previous one. The <code>containsHeader</code> method can be
230 * used to test for the presence of a header before setting its
231 * value.
232 *
233 * @param name the name of the header
234 * @param value the header value If it contains octet string,
235 * it should be encoded according to RFC 2047
236 * (http://www.ietf.org/rfc/rfc2047.txt)
237 *
238 * @see #containsHeader
239 * @see #addHeader
240 */
241
242 public void setHeader(String name, String value);
243
244 /**
245 * Adds a response header with the given name and value.
246 * This method allows response headers to have multiple values.
247 *
248 * @param name the name of the header
249 * @param value the additional header value If it contains
250 * octet string, it should be encoded
251 * according to RFC 2047
252 * (http://www.ietf.org/rfc/rfc2047.txt)
253 *
254 * @see #setHeader
255 */
256
257 public void addHeader(String name, String value);
258
259 /**
260 * Sets a response header with the given name and
261 * integer value. If the header had already been set, the new value
262 * overwrites the previous one. The <code>containsHeader</code>
263 * method can be used to test for the presence of a header before
264 * setting its value.
265 *
266 * @param name the name of the header
267 * @param value the assigned integer value
268 *
269 * @see #containsHeader
270 * @see #addIntHeader
271 */
272
273 public void setIntHeader(String name, int value);
274
275 /**
276 * Adds a response header with the given name and
277 * integer value. This method allows response headers to have multiple
278 * values.
279 *
280 * @param name the name of the header
281 * @param value the assigned integer value
282 *
283 * @see #setIntHeader
284 */
285
286 public void addIntHeader(String name, int value);
287
288 /**
289 * Sets the status code for this response. This method is used to
290 * set the return status code when there is no error (for example,
291 * for the status codes SC_OK or SC_MOVED_TEMPORARILY). If there
292 * is an error, and the caller wishes to invoke an error-page defined
293 * in the web application, the <code>sendError</code> method should be used
294 * instead.
295 * <p> The container clears the buffer and sets the Location header, preserving
296 * cookies and other headers.
297 *
298 * @param sc the status code
299 *
300 * @see #sendError
301 */
302
303 public void setStatus(int sc);
304
305 /**
306 * @deprecated As of version 2.1, due to ambiguous meaning of the
307 * message parameter. To set a status code
308 * use <code>setStatus(int)</code>, to send an error with a description
309 * use <code>sendError(int, String)</code>.
310 *
311 * Sets the status code and message for this response.
312 *
313 * @param sc the status code
314 * @param sm the status message
315 */
316
317 public void setStatus(int sc, String sm);
318
319 /*
320 * Server status codes; see RFC 2068.
321 */
322
323 /**
324 * Status code (100) indicating the client can continue.
325 */
326
327 public static final int SC_CONTINUE = 100;
328
329 /**
330 * Status code (101) indicating the server is switching protocols
331 * according to Upgrade header.
332 */
333
334 public static final int SC_SWITCHING_PROTOCOLS = 101;
335
336 /**
337 * Status code (200) indicating the request succeeded normally.
338 */
339
340 public static final int SC_OK = 200;
341
342 /**
343 * Status code (201) indicating the request succeeded and created
344 * a new resource on the server.
345 */
346
347 public static final int SC_CREATED = 201;
348
349 /**
350 * Status code (202) indicating that a request was accepted for
351 * processing, but was not completed.
352 */
353
354 public static final int SC_ACCEPTED = 202;
355
356 /**
357 * Status code (203) indicating that the meta information presented
358 * by the client did not originate from the server.
359 */
360
361 public static final int SC_NON_AUTHORITATIVE_INFORMATION = 203;
362
363 /**
364 * Status code (204) indicating that the request succeeded but that
365 * there was no new information to return.
366 */
367
368 public static final int SC_NO_CONTENT = 204;
369
370 /**
371 * Status code (205) indicating that the agent <em>SHOULD</em> reset
372 * the document view which caused the request to be sent.
373 */
374
375 public static final int SC_RESET_CONTENT = 205;
376
377 /**
378 * Status code (206) indicating that the server has fulfilled
379 * the partial GET request for the resource.
380 */
381
382 public static final int SC_PARTIAL_CONTENT = 206;
383
384 /**
385 * Status code (300) indicating that the requested resource
386 * corresponds to any one of a set of representations, each with
387 * its own specific location.
388 */
389
390 public static final int SC_MULTIPLE_CHOICES = 300;
391
392 /**
393 * Status code (301) indicating that the resource has permanently
394 * moved to a new location, and that future references should use a
395 * new URI with their requests.
396 */
397
398 public static final int SC_MOVED_PERMANENTLY = 301;
399
400 /**
401 * Status code (302) indicating that the resource has temporarily
402 * moved to another location, but that future references should
403 * still use the original URI to access the resource.
404 *
405 * This definition is being retained for backwards compatibility.
406 * SC_FOUND is now the preferred definition.
407 */
408
409 public static final int SC_MOVED_TEMPORARILY = 302;
410
411 /**
412 * Status code (302) indicating that the resource reside
413 * temporarily under a different URI. Since the redirection might
414 * be altered on occasion, the client should continue to use the
415 * Request-URI for future requests.(HTTP/1.1) To represent the
416 * status code (302), it is recommended to use this variable.
417 */
418
419 public static final int SC_FOUND = 302;
420
421 /**
422 * Status code (303) indicating that the response to the request
423 * can be found under a different URI.
424 */
425
426 public static final int SC_SEE_OTHER = 303;
427
428 /**
429 * Status code (304) indicating that a conditional GET operation
430 * found that the resource was available and not modified.
431 */
432
433 public static final int SC_NOT_MODIFIED = 304;
434
435 /**
436 * Status code (305) indicating that the requested resource
437 * <em>MUST</em> be accessed through the proxy given by the
438 * <code><em>Location</em></code> field.
439 */
440
441 public static final int SC_USE_PROXY = 305;
442
443 /**
444 * Status code (307) indicating that the requested resource
445 * resides temporarily under a different URI. The temporary URI
446 * <em>SHOULD</em> be given by the <code><em>Location</em></code>
447 * field in the response.
448 */
449
450 public static final int SC_TEMPORARY_REDIRECT = 307;
451
452 /**
453 * Status code (400) indicating the request sent by the client was
454 * syntactically incorrect.
455 */
456
457 public static final int SC_BAD_REQUEST = 400;
458
459 /**
460 * Status code (401) indicating that the request requires HTTP
461 * authentication.
462 */
463
464 public static final int SC_UNAUTHORIZED = 401;
465
466 /**
467 * Status code (402) reserved for future use.
468 */
469
470 public static final int SC_PAYMENT_REQUIRED = 402;
471
472 /**
473 * Status code (403) indicating the server understood the request
474 * but refused to fulfill it.
475 */
476
477 public static final int SC_FORBIDDEN = 403;
478
479 /**
480 * Status code (404) indicating that the requested resource is not
481 * available.
482 */
483
484 public static final int SC_NOT_FOUND = 404;
485
486 /**
487 * Status code (405) indicating that the method specified in the
488 * <code><em>Request-Line</em></code> is not allowed for the resource
489 * identified by the <code><em>Request-URI</em></code>.
490 */
491
492 public static final int SC_METHOD_NOT_ALLOWED = 405;
493
494 /**
495 * Status code (406) indicating that the resource identified by the
496 * request is only capable of generating response entities which have
497 * content characteristics not acceptable according to the accept
498 * headers sent in the request.
499 */
500
501 public static final int SC_NOT_ACCEPTABLE = 406;
502
503 /**
504 * Status code (407) indicating that the client <em>MUST</em> first
505 * authenticate itself with the proxy.
506 */
507
508 public static final int SC_PROXY_AUTHENTICATION_REQUIRED = 407;
509
510 /**
511 * Status code (408) indicating that the client did not produce a
512 * request within the time that the server was prepared to wait.
513 */
514
515 public static final int SC_REQUEST_TIMEOUT = 408;
516
517 /**
518 * Status code (409) indicating that the request could not be
519 * completed due to a conflict with the current state of the
520 * resource.
521 */
522
523 public static final int SC_CONFLICT = 409;
524
525 /**
526 * Status code (410) indicating that the resource is no longer
527 * available at the server and no forwarding address is known.
528 * This condition <em>SHOULD</em> be considered permanent.
529 */
530
531 public static final int SC_GONE = 410;
532
533 /**
534 * Status code (411) indicating that the request cannot be handled
535 * without a defined <code><em>Content-Length</em></code>.
536 */
537
538 public static final int SC_LENGTH_REQUIRED = 411;
539
540 /**
541 * Status code (412) indicating that the precondition given in one
542 * or more of the request-header fields evaluated to false when it
543 * was tested on the server.
544 */
545
546 public static final int SC_PRECONDITION_FAILED = 412;
547
548 /**
549 * Status code (413) indicating that the server is refusing to process
550 * the request because the request entity is larger than the server is
551 * willing or able to process.
552 */
553
554 public static final int SC_REQUEST_ENTITY_TOO_LARGE = 413;
555
556 /**
557 * Status code (414) indicating that the server is refusing to service
558 * the request because the <code><em>Request-URI</em></code> is longer
559 * than the server is willing to interpret.
560 */
561
562 public static final int SC_REQUEST_URI_TOO_LONG = 414;
563
564 /**
565 * Status code (415) indicating that the server is refusing to service
566 * the request because the entity of the request is in a format not
567 * supported by the requested resource for the requested method.
568 */
569
570 public static final int SC_UNSUPPORTED_MEDIA_TYPE = 415;
571
572 /**
573 * Status code (416) indicating that the server cannot serve the
574 * requested byte range.
575 */
576
577 public static final int SC_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
578
579 /**
580 * Status code (417) indicating that the server could not meet the
581 * expectation given in the Expect request header.
582 */
583
584 public static final int SC_EXPECTATION_FAILED = 417;
585
586 /**
587 * Status code (500) indicating an error inside the HTTP server
588 * which prevented it from fulfilling the request.
589 */
590
591 public static final int SC_INTERNAL_SERVER_ERROR = 500;
592
593 /**
594 * Status code (501) indicating the HTTP server does not support
595 * the functionality needed to fulfill the request.
596 */
597
598 public static final int SC_NOT_IMPLEMENTED = 501;
599
600 /**
601 * Status code (502) indicating that the HTTP server received an
602 * invalid response from a server it consulted when acting as a
603 * proxy or gateway.
604 */
605
606 public static final int SC_BAD_GATEWAY = 502;
607
608 /**
609 * Status code (503) indicating that the HTTP server is
610 * temporarily overloaded, and unable to handle the request.
611 */
612
613 public static final int SC_SERVICE_UNAVAILABLE = 503;
614
615 /**
616 * Status code (504) indicating that the server did not receive
617 * a timely response from the upstream server while acting as
618 * a gateway or proxy.
619 */
620
621 public static final int SC_GATEWAY_TIMEOUT = 504;
622
623 /**
624 * Status code (505) indicating that the server does not support
625 * or refuses to support the HTTP protocol version that was used
626 * in the request message.
627 */
628
629 public static final int SC_HTTP_VERSION_NOT_SUPPORTED = 505;
630 }
|