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 import java.util.Collection;
024
025 import javax.servlet.ServletResponse;
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 * <p/>
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 * @version $Rev: 896175 $ $Date: 2010-01-05 13:46:13 -0500 (Tue, 05 Jan 2010) $
037 * @see javax.servlet.ServletResponse
038 */
039
040
041 public interface HttpServletResponse extends ServletResponse {
042 /*
043 * Server status codes; see RFC 2068.
044 */
045
046 /**
047 * Status code (100) indicating the client can continue.
048 */
049
050 int SC_CONTINUE = 100;
051
052
053 /**
054 * Status code (101) indicating the server is switching protocols
055 * according to Upgrade header.
056 */
057
058 int SC_SWITCHING_PROTOCOLS = 101;
059
060 /**
061 * Status code (200) indicating the request succeeded normally.
062 */
063
064 int SC_OK = 200;
065
066 /**
067 * Status code (201) indicating the request succeeded and created
068 * a new resource on the server.
069 */
070
071 int SC_CREATED = 201;
072
073 /**
074 * Status code (202) indicating that a request was accepted for
075 * processing, but was not completed.
076 */
077
078 int SC_ACCEPTED = 202;
079
080 /**
081 * Status code (203) indicating that the meta information presented
082 * by the client did not originate from the server.
083 */
084
085 int SC_NON_AUTHORITATIVE_INFORMATION = 203;
086
087 /**
088 * Status code (204) indicating that the request succeeded but that
089 * there was no new information to return.
090 */
091
092 int SC_NO_CONTENT = 204;
093
094 /**
095 * Status code (205) indicating that the agent <em>SHOULD</em> reset
096 * the document view which caused the request to be sent.
097 */
098
099 int SC_RESET_CONTENT = 205;
100
101 /**
102 * Status code (206) indicating that the server has fulfilled
103 * the partial GET request for the resource.
104 */
105
106 int SC_PARTIAL_CONTENT = 206;
107
108 /**
109 * Status code (300) indicating that the requested resource
110 * corresponds to any one of a set of representations, each with
111 * its own specific location.
112 */
113
114 int SC_MULTIPLE_CHOICES = 300;
115
116 /**
117 * Status code (301) indicating that the resource has permanently
118 * moved to a new location, and that future references should use a
119 * new URI with their requests.
120 */
121
122 int SC_MOVED_PERMANENTLY = 301;
123
124 /**
125 * Status code (302) indicating that the resource has temporarily
126 * moved to another location, but that future references should
127 * still use the original URI to access the resource.
128 * <p/>
129 * This definition is being retained for backwards compatibility.
130 * SC_FOUND is now the preferred definition.
131 */
132
133 int SC_MOVED_TEMPORARILY = 302;
134
135 /**
136 * Status code (302) indicating that the resource reside
137 * temporarily under a different URI. Since the redirection might
138 * be altered on occasion, the client should continue to use the
139 * Request-URI for future requests.(HTTP/1.1) To represent the
140 * status code (302), it is recommended to use this variable.
141 */
142
143 int SC_FOUND = 302;
144
145 /**
146 * Status code (303) indicating that the response to the request
147 * can be found under a different URI.
148 */
149
150 int SC_SEE_OTHER = 303;
151
152 /**
153 * Status code (304) indicating that a conditional GET operation
154 * found that the resource was available and not modified.
155 */
156
157 int SC_NOT_MODIFIED = 304;
158
159 /**
160 * Status code (305) indicating that the requested resource
161 * <em>MUST</em> be accessed through the proxy given by the
162 * <code><em>Location</em></code> field.
163 */
164
165 int SC_USE_PROXY = 305;
166
167 /**
168 * Status code (307) indicating that the requested resource
169 * resides temporarily under a different URI. The temporary URI
170 * <em>SHOULD</em> be given by the <code><em>Location</em></code>
171 * field in the response.
172 */
173
174 int SC_TEMPORARY_REDIRECT = 307;
175
176 /**
177 * Status code (400) indicating the request sent by the client was
178 * syntactically incorrect.
179 */
180
181 int SC_BAD_REQUEST = 400;
182
183 /**
184 * Status code (401) indicating that the request requires HTTP
185 * authentication.
186 */
187
188 int SC_UNAUTHORIZED = 401;
189
190 /**
191 * Status code (402) reserved for future use.
192 */
193
194 int SC_PAYMENT_REQUIRED = 402;
195
196 /**
197 * Status code (403) indicating the server understood the request
198 * but refused to fulfill it.
199 */
200
201 int SC_FORBIDDEN = 403;
202
203 /**
204 * Status code (404) indicating that the requested resource is not
205 * available.
206 */
207
208 int SC_NOT_FOUND = 404;
209
210 /**
211 * Status code (405) indicating that the method specified in the
212 * <code><em>Request-Line</em></code> is not allowed for the resource
213 * identified by the <code><em>Request-URI</em></code>.
214 */
215
216 int SC_METHOD_NOT_ALLOWED = 405;
217
218 /**
219 * Status code (406) indicating that the resource identified by the
220 * request is only capable of generating response entities which have
221 * content characteristics not acceptable according to the accept
222 * headers sent in the request.
223 */
224
225 int SC_NOT_ACCEPTABLE = 406;
226
227 /**
228 * Status code (407) indicating that the client <em>MUST</em> first
229 * authenticate itself with the proxy.
230 */
231
232 int SC_PROXY_AUTHENTICATION_REQUIRED = 407;
233
234 /**
235 * Status code (408) indicating that the client did not produce a
236 * request within the time that the server was prepared to wait.
237 */
238
239 int SC_REQUEST_TIMEOUT = 408;
240
241 /**
242 * Status code (409) indicating that the request could not be
243 * completed due to a conflict with the current state of the
244 * resource.
245 */
246
247 int SC_CONFLICT = 409;
248
249 /**
250 * Status code (410) indicating that the resource is no longer
251 * available at the server and no forwarding address is known.
252 * This condition <em>SHOULD</em> be considered permanent.
253 */
254
255 int SC_GONE = 410;
256
257 /**
258 * Status code (411) indicating that the request cannot be handled
259 * without a defined <code><em>Content-Length</em></code>.
260 */
261
262 int SC_LENGTH_REQUIRED = 411;
263
264 /**
265 * Status code (412) indicating that the precondition given in one
266 * or more of the request-header fields evaluated to false when it
267 * was tested on the server.
268 */
269
270 int SC_PRECONDITION_FAILED = 412;
271
272 /**
273 * Status code (413) indicating that the server is refusing to process
274 * the request because the request entity is larger than the server is
275 * willing or able to process.
276 */
277
278 int SC_REQUEST_ENTITY_TOO_LARGE = 413;
279
280 /**
281 * Status code (414) indicating that the server is refusing to service
282 * the request because the <code><em>Request-URI</em></code> is longer
283 * than the server is willing to interpret.
284 */
285
286 int SC_REQUEST_URI_TOO_LONG = 414;
287
288 /**
289 * Status code (415) indicating that the server is refusing to service
290 * the request because the entity of the request is in a format not
291 * supported by the requested resource for the requested method.
292 */
293
294 int SC_UNSUPPORTED_MEDIA_TYPE = 415;
295
296 /**
297 * Status code (416) indicating that the server cannot serve the
298 * requested byte range.
299 */
300
301 int SC_REQUESTED_RANGE_NOT_SATISFIABLE = 416;
302
303 /**
304 * Status code (417) indicating that the server could not meet the
305 * expectation given in the Expect request header.
306 */
307
308 int SC_EXPECTATION_FAILED = 417;
309
310 /**
311 * Status code (500) indicating an error inside the HTTP server
312 * which prevented it from fulfilling the request.
313 */
314
315 int SC_INTERNAL_SERVER_ERROR = 500;
316
317 /**
318 * Status code (501) indicating the HTTP server does not support
319 * the functionality needed to fulfill the request.
320 */
321
322 int SC_NOT_IMPLEMENTED = 501;
323
324 /**
325 * Status code (502) indicating that the HTTP server received an
326 * invalid response from a server it consulted when acting as a
327 * proxy or gateway.
328 */
329
330 int SC_BAD_GATEWAY = 502;
331
332 /**
333 * Status code (503) indicating that the HTTP server is
334 * temporarily overloaded, and unable to handle the request.
335 */
336
337 int SC_SERVICE_UNAVAILABLE = 503;
338
339 /**
340 * Status code (504) indicating that the server did not receive
341 * a timely response from the upstream server while acting as
342 * a gateway or proxy.
343 */
344
345 int SC_GATEWAY_TIMEOUT = 504;
346
347 /**
348 * Status code (505) indicating that the server does not support
349 * or refuses to support the HTTP protocol version that was used
350 * in the request message.
351 */
352
353 int SC_HTTP_VERSION_NOT_SUPPORTED = 505;
354
355 /**
356 * Adds the specified cookie to the response. This method can be called
357 * multiple times to set more than one cookie.
358 *
359 * @param cookie the Cookie to return to the client
360 */
361
362 void addCookie(Cookie cookie);
363
364 /**
365 * Adds a response header with the given name and
366 * date-value. The date is specified in terms of
367 * milliseconds since the epoch. This method allows response headers
368 * to have multiple values.
369 *
370 * @param name the name of the header to set
371 * @param date the additional date value
372 * @see #setDateHeader
373 */
374
375 void addDateHeader(String name, long date);
376
377 /**
378 * Adds a response header with the given name and value.
379 * This method allows response headers to have multiple values.
380 *
381 * @param name the name of the header
382 * @param value the additional header value If it contains
383 * octet string, it should be encoded
384 * according to RFC 2047
385 * (http://www.ietf.org/rfc/rfc2047.txt)
386 * @see #setHeader
387 */
388 void addHeader(String name, String value);
389
390 /**
391 * Adds a response header with the given name and
392 * integer value. This method allows response headers to have multiple
393 * values.
394 *
395 * @param name the name of the header
396 * @param value the assigned integer value
397 * @see #setIntHeader
398 */
399 void addIntHeader(String name, int value);
400
401 /**
402 * Returns a boolean indicating whether the named response header
403 * has already been set.
404 *
405 * @param name the header name
406 * @return <code>true</code> if the named response header
407 * has already been set;
408 * <code>false</code> otherwise
409 */
410 boolean containsHeader(String name);
411
412 /**
413 * Encodes the specified URL by including the session ID in it,
414 * or, if encoding is not needed, returns the URL unchanged.
415 * The implementation of this method includes the logic to
416 * determine whether the session ID needs to be encoded in the URL.
417 * For example, if the browser supports cookies, or session
418 * tracking is turned off, URL encoding is unnecessary.
419 * <p/>
420 * <p>For robust session tracking, all URLs emitted by a servlet
421 * should be run through this
422 * method. Otherwise, URL rewriting cannot be used with browsers
423 * which do not support cookies.
424 *
425 * @param url the url to be encoded.
426 * @return the encoded URL if encoding is needed;
427 * the unchanged URL otherwise.
428 */
429 String encodeURL(String url);
430
431 /**
432 * Encodes the specified URL for use in the
433 * <code>sendRedirect</code> method or, if encoding is not needed,
434 * returns the URL unchanged. The implementation of this method
435 * includes the logic to determine whether the session ID
436 * needs to be encoded in the URL. Because the rules for making
437 * this determination can differ from those used to decide whether to
438 * encode a normal link, this method is separated from the
439 * <code>encodeURL</code> method.
440 * <p/>
441 * <p>All URLs sent to the <code>HttpServletResponse.sendRedirect</code>
442 * method should be run through this method. Otherwise, URL
443 * rewriting cannot be used with browsers which do not support
444 * cookies.
445 *
446 * @param url the url to be encoded.
447 * @return the encoded URL if encoding is needed;
448 * the unchanged URL otherwise.
449 * @see #sendRedirect
450 * @see #encodeUrl
451 */
452 String encodeRedirectURL(String url);
453
454 /**
455 * @param url the url to be encoded.
456 * @return the encoded URL if encoding is needed;
457 * the unchanged URL otherwise.
458 * @deprecated As of version 2.1, use encodeURL(String url) instead
459 */
460 String encodeUrl(String url);
461
462 /**
463 * @param url the url to be encoded.
464 * @return the encoded URL if encoding is needed;
465 * the unchanged URL otherwise.
466 * @deprecated As of version 2.1, use
467 * encodeRedirectURL(String url) instead
468 */
469 String encodeRedirectUrl(String url);
470
471 /**
472 * @param name header name
473 * @return header value
474 * @since 3.0
475 */
476 String getHeader(String name);
477
478 /**
479 * @return all the header names
480 * @since 3.0
481 */
482 Collection<String> getHeaderNames();
483
484 /**
485 * @param headerName header name for which headers are requested
486 * @return all the header values
487 * @since 3.0
488 */
489 Collection<String> getHeaders(String headerName);
490
491 /**
492 * @return current http status
493 * @since 3.0
494 */
495 int getStatus();
496
497 /**
498 * Sends an error response to the client using the specified status
499 * code and clearing the buffer.
500 * <p>If the response has already been committed, this method throws
501 * an IllegalStateException.
502 * After using this method, the response should be considered
503 * to be committed and should not be written to.
504 *
505 * @param sc the error status code
506 * @throws IOException If an input or output exception occurs
507 * @throws IllegalStateException If the response was committed
508 * before this method call
509 */
510 void sendError(int sc) throws IOException;
511
512 /**
513 * Sends an error response to the client using the specified
514 * status. The server defaults to creating the
515 * response to look like an HTML-formatted server error page
516 * containing the specified message, setting the content type
517 * to "text/html", leaving cookies and other headers unmodified.
518 * <p/>
519 * If an error-page declaration has been made for the web application
520 * corresponding to the status code passed in, it will be served back in
521 * preference to the suggested msg parameter.
522 * <p/>
523 * <p>If the response has already been committed, this method throws
524 * an IllegalStateException.
525 * After using this method, the response should be considered
526 * to be committed and should not be written to.
527 *
528 * @param sc the error status code
529 * @param msg the descriptive message
530 * @throws IOException If an input or output exception occurs
531 * @throws IllegalStateException If the response was committed
532 */
533 void sendError(int sc, String msg) throws IOException;
534
535 /**
536 * Sends a temporary redirect response to the client using the
537 * specified redirect location URL. This method can accept relative URLs;
538 * the servlet container must convert the relative URL to an absolute URL
539 * before sending the response to the client. If the location is relative
540 * without a leading '/' the container interprets it as relative to
541 * the current request URI. If the location is relative with a leading
542 * '/' the container interprets it as relative to the servlet container root.
543 * <p/>
544 * <p>If the response has already been committed, this method throws
545 * an IllegalStateException.
546 * After using this method, the response should be considered
547 * to be committed and should not be written to.
548 *
549 * @param location the redirect location URL
550 * @throws IOException If an input or output exception occurs
551 * @throws IllegalStateException If the response was committed or
552 * if a partial URL is given and cannot be converted into a valid URL
553 */
554 void sendRedirect(String location) throws IOException;
555
556 /**
557 * Sets a response header with the given name and
558 * date-value. The date is specified in terms of
559 * milliseconds since the epoch. If the header had already
560 * been set, the new value overwrites the previous one. The
561 * <code>containsHeader</code> method can be used to test for the
562 * presence of a header before setting its value.
563 *
564 * @param name the name of the header to set
565 * @param date the assigned date value
566 * @see #containsHeader
567 * @see #addDateHeader
568 */
569 void setDateHeader(String name, long date);
570
571 /**
572 * Sets a response header with the given name and value.
573 * If the header had already been set, the new value overwrites the
574 * previous one. The <code>containsHeader</code> method can be
575 * used to test for the presence of a header before setting its
576 * value.
577 *
578 * @param name the name of the header
579 * @param value the header value If it contains octet string,
580 * it should be encoded according to RFC 2047
581 * (http://www.ietf.org/rfc/rfc2047.txt)
582 * @see #containsHeader
583 * @see #addHeader
584 */
585 void setHeader(String name, String value);
586
587 /**
588 * Sets a response header with the given name and
589 * integer value. If the header had already been set, the new value
590 * overwrites the previous one. The <code>containsHeader</code>
591 * method can be used to test for the presence of a header before
592 * setting its value.
593 *
594 * @param name the name of the header
595 * @param value the assigned integer value
596 * @see #containsHeader
597 * @see #addIntHeader
598 */
599 void setIntHeader(String name, int value);
600
601 /**
602 * Sets the status code for this response. This method is used to
603 * set the return status code when there is no error (for example,
604 * for the status codes SC_OK or SC_MOVED_TEMPORARILY). If there
605 * is an error, and the caller wishes to invoke an error-page defined
606 * in the web application, the <code>sendError</code> method should be used
607 * instead.
608 * <p> The container clears the buffer and sets the Location header, preserving
609 * cookies and other headers.
610 *
611 * @param sc the status code
612 * @see #sendError
613 */
614 void setStatus(int sc);
615
616 /**
617 * @param sc the status code
618 * @param sm the status message
619 * @deprecated As of version 2.1, due to ambiguous meaning of the
620 * message parameter. To set a status code
621 * use <code>setStatus(int)</code>, to send an error with a description
622 * use <code>sendError(int, String)</code>.
623 * <p/>
624 * Sets the status code and message for this response.
625 */
626 void setStatus(int sc, String sm);
627
628 }