001 /**
002 *
003 * Copyright 2003-2004 The Apache Software Foundation
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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
018 //
019 // This source code implements specifications defined by the Java
020 // Community Process. In order to remain compliant with the specification
021 // DO NOT add / change / or delete method signatures!
022 //
023
024 package javax.servlet.http;
025
026 import java.io.IOException;
027 import javax.servlet.ServletResponse;
028
029 /**
030 * Extends the {@link ServletResponse} interface to provide HTTP-specific
031 * functionality in sending a response. For example, it has methods
032 * to access HTTP headers and cookies.
033 *
034 * <p>The servlet container creates an <code>HttpServletResponse</code> object
035 * and passes it as an argument to the servlet's service methods
036 * (<code>doGet</code>, <code>doPost</code>, etc).
037 *
038 * @see javax.servlet.ServletResponse
039 *
040 * @version $Rev: 46019 $ $Date: 2004-09-14 02:56:06 -0700 (Tue, 14 Sep 2004) $
041 */
042 public interface HttpServletResponse extends ServletResponse {
043 /**
044 * Adds the specified cookie to the response. This method can be called
045 * multiple times to set more than one cookie.
046 *
047 * @param cookie the Cookie to return to the client
048 */
049 public void addCookie(Cookie cookie);
050
051 /**
052 * Returns a boolean indicating whether the named response header has
053 * already been set.
054 *
055 * @param name the header name
056 * @return <code>true</code> if the named response header has already been
057 * set; <code>false</code> otherwise
058 */
059 public boolean containsHeader(String name);
060
061 /**
062 * Encodes the specified URL by including the session ID in it,
063 * or, if encoding is not needed, returns the URL unchanged.
064 * The implementation of this method includes the logic to
065 * determine whether the session ID needs to be encoded in the URL.
066 * For example, if the browser supports cookies, or session
067 * tracking is turned off, URL encoding is unnecessary.
068 *
069 * <p>For robust session tracking, all URLs emitted by a servlet
070 * should be run through this
071 * method. Otherwise, URL rewriting cannot be used with browsers
072 * which do not support cookies.
073 *
074 * @param url the url to be encoded.
075 * @return the encoded URL if encoding is needed; the unchanged URL
076 * otherwise.
077 */
078 public String encodeURL(String url);
079
080 /**
081 * Encodes the specified URL for use in the
082 * <code>sendRedirect</code> method or, if encoding is not needed,
083 * returns the URL unchanged. The implementation of this method
084 * includes the logic to determine whether the session ID
085 * needs to be encoded in the URL. Because the rules for making
086 * this determination can differ from those used to decide whether to
087 * encode a normal link, this method is separete from the
088 * <code>encodeURL</code> method.
089 *
090 * <p>All URLs sent to the <code>HttpServletResponse.sendRedirect</code>
091 * method should be run through this method. Otherwise, URL
092 * rewriting cannot be used with browsers which do not support
093 * cookies.
094 *
095 * @param url the url to be encoded.
096 * @return the encoded URL if encoding is needed; the unchanged URL
097 * otherwise.
098 *
099 * @see #sendRedirect
100 * @see #encodeUrl
101 */
102 public String encodeRedirectURL(String url);
103
104 /**
105 * @deprecated As of version 2.1, use encodeURL(String url) instead
106 *
107 * @param url the url to be encoded.
108 * @return the encoded URL if encoding is needed; the unchanged URL
109 * otherwise.
110 */
111 public String encodeUrl(String url);
112
113 /**
114 * @deprecated As of version 2.1, use encodeRedirectURL(String url) instead
115 *
116 * @param url the url to be encoded.
117 * @return the encoded URL if encoding is needed; the unchanged URL
118 * otherwise.
119 */
120 public String encodeRedirectUrl(String url);
121
122 /**
123 * Sends an error response to the client using the specified
124 * status. The server defaults to creating the
125 * response to look like an HTML-formatted server error page
126 * containing the specified message, setting the content type
127 * to "text/html", leaving cookies and other headers unmodified.
128 *
129 * If an error-page declaration has been made for the web application
130 * corresponding to the status code passed in, it will be served back in
131 * preference to the suggested msg parameter.
132 *
133 * <p>If the response has already been committed, this method throws
134 * an IllegalStateException.
135 * After using this method, the response should be considered
136 * to be committed and should not be written to.
137 *
138 * @param sc the error status code
139 * @param msg the descriptive message
140 * @exception IOException If an input or output exception occurs
141 * @exception IllegalStateException If the response was committed
142 */
143 public void sendError(int sc, String msg) throws IOException;
144
145 /**
146 * Sends an error response to the client using the specified status
147 * code and clearing the buffer.
148 * <p>If the response has already been committed, this method throws
149 * an IllegalStateException.
150 * After using this method, the response should be considered
151 * to be committed and should not be written to.
152 *
153 * @param sc the error status code
154 * @exception IOException If an input or output exception occurs
155 * @exception IllegalStateException If the response was committed
156 * before this method call
157 */
158 public void sendError(int sc) throws IOException;
159
160 /**
161 * Sends a temporary redirect response to the client using the
162 * specified redirect location URL. This method can accept relative URLs;
163 * the servlet container must convert the relative URL to an absolute URL
164 * before sending the response to the client. If the location is relative
165 * without a leading '/' the container interprets it as relative to
166 * the current request URI. If the location is relative with a leading
167 * '/' the container interprets it as relative to the servlet container root.
168 *
169 * <p>If the response has already been committed, this method throws
170 * an IllegalStateException.
171 * After using this method, the response should be considered
172 * to be committed and should not be written to.
173 *
174 * @param location the redirect location URL
175 * @exception IOException If an input or output exception occurs
176 * @exception IllegalStateException If the response was committed or
177 * if a partial URL is given and cannot be converted into a valid URL
178 */
179 public void sendRedirect(String location) throws IOException;
180
181 /**
182 * Sets a response header with the given name and
183 * date-value. The date is specified in terms of
184 * milliseconds since the epoch. If the header had already
185 * been set, the new value overwrites the previous one. The
186 * <code>containsHeader</code> method can be used to test for the
187 * presence of a header before setting its value.
188 *
189 * @param name the name of the header to set
190 * @param date the assigned date value
191 *
192 * @see #containsHeader
193 * @see #addDateHeader
194 */
195 public void setDateHeader(String name, long date);
196
197 /**
198 * Adds a response header with the given name and
199 * date-value. The date is specified in terms of
200 * milliseconds since the epoch. This method allows response headers
201 * to have multiple values.
202 *
203 * @param name the name of the header to set
204 * @param date the additional date value
205 *
206 * @see #setDateHeader
207 */
208 public void addDateHeader(String name, long date);
209
210 /**
211 * Sets a response header with the given name and value.
212 * If the header had already been set, the new value overwrites the
213 * previous one. The <code>containsHeader</code> method can be
214 * used to test for the presence of a header before setting its
215 * value.
216 *
217 * @param name the name of the header
218 * @param value the header value If it contains octet string,
219 * it should be encoded according to RFC 2047
220 * (http://www.ietf.org/rfc/rfc2047.txt)
221 *
222 * @see #containsHeader
223 * @see #addHeader
224 */
225 public void setHeader(String name, String value);
226
227 /**
228 * Adds a response header with the given name and value.
229 * This method allows response headers to have multiple values.
230 *
231 * @param name the name of the header
232 * @param value the additional header value If it contains octet string,
233 * it should be encoded according to RFC 2047
234 * (http://www.ietf.org/rfc/rfc2047.txt)
235 *
236 * @see #setHeader
237 */
238 public void addHeader(String name, String value);
239
240 /**
241 * Sets a response header with the given name and
242 * integer value. If the header had already been set, the new value
243 * overwrites the previous one. The <code>containsHeader</code>
244 * method can be used to test for the presence of a header before
245 * setting its value.
246 *
247 * @param name the name of the header
248 * @param value the assigned integer value
249 *
250 * @see #containsHeader
251 * @see #addIntHeader
252 */
253 public void setIntHeader(String name, int value);
254
255 /**
256 * Adds a response header with the given name and
257 * integer value. This method allows response headers to have multiple
258 * values.
259 *
260 * @param name the name of the header
261 * @param value the assigned integer value
262 *
263 * @see #setIntHeader
264 */
265 public void addIntHeader(String name, int value);
266
267 /**
268 * Sets the status code for this response. This method is used to
269 * set the return status code when there is no error (for example,
270 * for the status codes SC_OK or SC_MOVED_TEMPORARILY). If there
271 * is an error, and the caller wishes to invoke an error-page defined
272 * in the web applicaion, the <code>sendError</code> method should be used
273 * instead.
274 * <p> The container clears the buffer and sets the Location header, preserving
275 * cookies and other headers.
276 *
277 * @param sc the status code
278 *
279 * @see #sendError
280 */
281 public void setStatus(int sc);
282
283 /**
284 * @deprecated As of version 2.1, due to ambiguous meaning of the
285 * message parameter. To set a status code
286 * use <code>setStatus(int)</code>, to send an error with a description
287 * use <code>sendError(int, String)</code>.
288 *
289 * Sets the status code and message for this response.
290 *
291 * @param sc the status code
292 * @param sm the status message
293 */
294 public void setStatus(int sc, String sm);
295
296 //
297 // Server status codes; see RFC 2068.
298 //
299
300 /**
301 * Status code (100) indicating the client can continue.
302 */
303 public static final int SC_CONTINUE = 100;
304
305 /**
306 * Status code (101) indicating the server is switching protocols
307 * according to Upgrade header.
308 */
309 public static final int SC_SWITCHING_PROTOCOLS = 101;
310
311 /**
312 * Status code (200) indicating the request succeeded normally.
313 */
314 public static final int SC_OK = 200;
315
316 /**
317 * Status code (201) indicating the request succeeded and created
318 * a new resource on the server.
319 */
320 public static final int SC_CREATED = 201;
321
322 /**
323 * Status code (202) indicating that a request was accepted for
324 * processing, but was not completed.
325 */
326 public static final int SC_ACCEPTED = 202;
327
328 /**
329 * Status code (203) indicating that the meta information presented
330 * by the client did not originate from the server.
331 */
332 public static final int SC_NON_AUTHORITATIVE_INFORMATION = 203;
333
334 /**
335 * Status code (204) indicating that the request succeeded but that
336 * there was no new information to return.
337 */
338 public static final int SC_NO_CONTENT = 204;
339
340 /**
341 * Status code (205) indicating that the agent <em>SHOULD</em> reset
342 * the document view which caused the request to be sent.
343 */
344 public static final int SC_RESET_CONTENT = 205;
345
346 /**
347 * Status code (206) indicating that the server has fulfilled
348 * the partial GET request for the resource.
349 */
350 public static final int SC_PARTIAL_CONTENT = 206;
351
352 /**
353 * Status code (300) indicating that the requested resource
354 * corresponds to any one of a set of representations, each with
355 * its own specific location.
356 */
357 public static final int SC_MULTIPLE_CHOICES = 300;
358
359 /**
360 * Status code (301) indicating that the resource has permanently
361 * moved to a new location, and that future references should use a
362 * new URI with their requests.
363 */
364 public static final int SC_MOVED_PERMANENTLY = 301;
365
366 /**
367 * Status code (302) indicating that the resource has temporarily
368 * moved to another location, but that future references should
369 * still use the original URI to access the resource.
370 *
371 * This definition is being retained for backwards compatibility.
372 * SC_FOUND is now the preferred definition.
373 */
374 public static final int SC_MOVED_TEMPORARILY = 302;
375
376 /**
377 * Status code (302) indicating that the resource reside
378 * temporarily under a different URI. Since the redirection might
379 * be altered on occasion, the client should continue to use the
380 * Request-URI for future requests.(HTTP/1.1) To represent the
381 * status code (302), it is recommended to use this variable.
382 */
383 public static final int SC_FOUND = 302;
384
385 /**
386 * Status code (303) indicating that the response to the request
387 * can be found under a different URI.
388 */
389 public static final int SC_SEE_OTHER = 303;
390
391 /**
392 * Status code (304) indicating that a conditional GET operation
393 * found that the resource was available and not modified.
394 */
395 public static final int SC_NOT_MODIFIED = 304;
396
397 /**
398 * Status code (305) indicating that the requested resource
399 * <em>MUST</em> be accessed through the proxy given by the
400 * <code><em>Location</em></code> field.
401 */
402 public static final int SC_USE_PROXY = 305;
403
404 /**
405 * Status code (307) indicating that the requested resource
406 * resides temporarily under a different URI. The temporary URI
407 * <em>SHOULD</em> be given by the <code><em>Location</em></code>
408 * field in the response.
409 */
410 public static final int SC_TEMPORARY_REDIRECT = 307;
411
412 /**
413 * Status code (400) indicating the request sent by the client was
414 * syntactically incorrect.
415 */
416 public static final int SC_BAD_REQUEST = 400;
417
418 /**
419 * Status code (401) indicating that the request requires HTTP
420 * authentication.
421 */
422 public static final int SC_UNAUTHORIZED = 401;
423
424 /**
425 * Status code (402) reserved for future use.
426 */
427 public static final int SC_PAYMENT_REQUIRED = 402;
428
429 /**
430 * Status code (403) indicating the server understood the request
431 * but refused to fulfill it.
432 */
433 public static final int SC_FORBIDDEN = 403;
434
435 /**
436 * Status code (404) indicating that the requested resource is not
437 * available.
438 */
439 public static final int SC_NOT_FOUND = 404;
440
441 /**
442 * Status code (405) indicating that the method specified in the
443 * <code><em>Request-Line</em></code> is not allowed for the resource
444 * identified by the <code><em>Request-URI</em></code>.
445 */
446 public static final int SC_METHOD_NOT_ALLOWED = 405;
447
448 /**
449 * Status code (406) indicating that the resource identified by the
450 * request is only capable of generating response entities which have
451 * content characteristics not acceptable according to the accept
452 * headers sent in the request.
453 */
454 public static final int SC_NOT_ACCEPTABLE = 406;
455
456 /**
457 * Status code (407) indicating that the client <em>MUST</em> first
458 * authenticate itself with the proxy.
459 */
460 public static final int SC_PROXY_AUTHENTICATION_REQUIRED = 407;
461
462 /**
463 * Status code (408) indicating that the client did not produce a
464 * request within the time that the server was prepared to wait.
465 */
466 public static final int SC_REQUEST_TIMEOUT = 408;
467
468 /**
469 * Status code (409) indicating that the request could not be
470 * completed due to a conflict with the current state of the
471 * resource.
472 */
473 public static final int SC_CONFLICT = 409;
474
475 /**
476 * Status code (410) indicating that the resource is no longer
477 * available at the server and no forwarding address is known.
478 * This condition <em>SHOULD</em> be considered permanent.
479 */
480 public static final int SC_GONE = 410;
481
482 /**
483 * Status code (411) indicating that the request cannot be handled
484 * without a defined <code><em>Content-Length</em></code>.
485 */
486 public static final int SC_LENGTH_REQUIRED = 411;
487
488 /**
489 * Status code (412) indicating that the precondition given in one
490 * or more of the request-header fields evaluated to false when it
491 * was tested on the server.
492 */
493 public static final int SC_PRECONDITION_FAILED = 412;
494
495 /**
496 * Status code (413) indicating that the server is refusing to process
497 * the request because the request entity is larger than the server is
498 * willing or able to process.
499 */
500 public static final int SC_REQUEST_ENTITY_TOO_LARGE = 413;
501
502 /**
503 * Status code (414) indicating that the server is refusing to service
504 * the request because the <code><em>Request-URI</em></code> is longer
505 * than the server is willing to interpret.
506 */
507 public static final int SC_REQUEST_URI_TOO_LONG = 414;
508
509 /**
510 * Status code (415) indicating that the server is refusing to service
511 * the request because the entity of the request is in a format not
512 * supported by the requested resource for the requested method.
513 */
514 public static final int SC_UNSUPPORTED_MEDIA_TYPE = 415;
515
516 /**
517 * Status code (416) indicating that the server cannot serve the
518 * requested byte range.
519 */
520 public static final int SC_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
521
522 /**
523 * Status code (417) indicating that the server could not meet the
524 * expectation given in the Expect request header.
525 */
526 public static final int SC_EXPECTATION_FAILED = 417;
527
528 /**
529 * Status code (500) indicating an error inside the HTTP server
530 * which prevented it from fulfilling the request.
531 */
532 public static final int SC_INTERNAL_SERVER_ERROR = 500;
533
534 /**
535 * Status code (501) indicating the HTTP server does not support
536 * the functionality needed to fulfill the request.
537 */
538 public static final int SC_NOT_IMPLEMENTED = 501;
539
540 /**
541 * Status code (502) indicating that the HTTP server received an
542 * invalid response from a server it consulted when acting as a
543 * proxy or gateway.
544 */
545 public static final int SC_BAD_GATEWAY = 502;
546
547 /**
548 * Status code (503) indicating that the HTTP server is
549 * temporarily overloaded, and unable to handle the request.
550 */
551 public static final int SC_SERVICE_UNAVAILABLE = 503;
552
553 /**
554 * Status code (504) indicating that the server did not receive
555 * a timely response from the upstream server while acting as
556 * a gateway or proxy.
557 */
558 public static final int SC_GATEWAY_TIMEOUT = 504;
559
560 /**
561 * Status code (505) indicating that the server does not support
562 * or refuses to support the HTTP protocol version that was used
563 * in the request message.
564 */
565 public static final int SC_HTTP_VERSION_NOT_SUPPORTED = 505;
566 }