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1   
2   
3   /*
4    * The contents of this file are subject to the terms
5    * of the Common Development and Distribution License
6    * (the "License").  You may not use this file except
7    * in compliance with the License.
8    *
9    * You can obtain a copy of the license at
10   * glassfish/bootstrap/legal/CDDLv1.0.txt or
11   * https://glassfish.dev.java.net/public/CDDLv1.0.html.
12   * See the License for the specific language governing
13   * permissions and limitations under the License.
14   *
15   * When distributing Covered Code, include this CDDL
16   * HEADER in each file and include the License file at
17   * glassfish/bootstrap/legal/CDDLv1.0.txt.  If applicable,
18   * add the following below this CDDL HEADER, with the
19   * fields enclosed by brackets "[]" replaced with your
20   * own identifying information: Portions Copyright [yyyy]
21   * [name of copyright owner]
22   *
23   * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
24   *
25   * Portions Copyright Apache Software Foundation.
26   */ 
27  
28  package javax.servlet.http;
29  
30  import java.text.MessageFormat;
31  import java.util.ResourceBundle;
32  
33  /**
34   *
35   * Creates a cookie, a small amount of information sent by a servlet to 
36   * a Web browser, saved by the browser, and later sent back to the server.
37   * A cookie's value can uniquely 
38   * identify a client, so cookies are commonly used for session management.
39   * 
40   * <p>A cookie has a name, a single value, and optional attributes
41   * such as a comment, path and domain qualifiers, a maximum age, and a
42   * version number. Some Web browsers have bugs in how they handle the 
43   * optional attributes, so use them sparingly to improve the interoperability 
44   * of your servlets.
45   *
46   * <p>The servlet sends cookies to the browser by using the
47   * {@link HttpServletResponse#addCookie} method, which adds
48   * fields to HTTP response headers to send cookies to the 
49   * browser, one at a time. The browser is expected to 
50   * support 20 cookies for each Web server, 300 cookies total, and
51   * may limit cookie size to 4 KB each.
52   * 
53   * <p>The browser returns cookies to the servlet by adding 
54   * fields to HTTP request headers. Cookies can be retrieved
55   * from a request by using the {@link HttpServletRequest#getCookies} method.
56   * Several cookies might have the same name but different path attributes.
57   * 
58   * <p>Cookies affect the caching of the Web pages that use them. 
59   * HTTP 1.0 does not cache pages that use cookies created with
60   * this class. This class does not support the cache control
61   * defined with HTTP 1.1.
62   *
63   * <p>This class supports both the Version 0 (by Netscape) and Version 1 
64   * (by RFC 2109) cookie specifications. By default, cookies are
65   * created using Version 0 to ensure the best interoperability.
66   *
67   *
68   * @author	Various
69   */
70  
71  // XXX would implement java.io.Serializable too, but can't do that
72  // so long as sun.servlet.* must run on older JDK 1.02 JVMs which
73  // don't include that support.
74  
75  public class Cookie implements Cloneable {
76  
77      private static final String LSTRING_FILE =
78  	"javax.servlet.http.LocalStrings";
79      private static ResourceBundle lStrings =
80  	ResourceBundle.getBundle(LSTRING_FILE);
81      
82      //
83      // The value of the cookie itself.
84      //
85      
86      private String name;	// NAME= ... "$Name" style is reserved
87      private String value;	// value of NAME
88  
89      //
90      // Attributes encoded in the header's cookie fields.
91      //
92      
93      private String comment;	// ;Comment=VALUE ... describes cookie's use
94  				// ;Discard ... implied by maxAge < 0
95      private String domain;	// ;Domain=VALUE ... domain that sees cookie
96      private int maxAge = -1;	// ;Max-Age=VALUE ... cookies auto-expire
97      private String path;	// ;Path=VALUE ... URLs that see the cookie
98      private boolean secure;	// ;Secure ... e.g. use SSL
99      private int version = 0;	// ;Version=1 ... means RFC 2109++ style
100     
101     
102 
103     /**
104      * Constructs a cookie with a specified name and value.
105      *
106      * <p>The name must conform to RFC 2109. That means it can contain 
107      * only ASCII alphanumeric characters and cannot contain commas, 
108      * semicolons, or white space or begin with a $ character. The cookie's
109      * name cannot be changed after creation.
110      *
111      * <p>The value can be anything the server chooses to send. Its
112      * value is probably of interest only to the server. The cookie's
113      * value can be changed after creation with the
114      * <code>setValue</code> method.
115      *
116      * <p>By default, cookies are created according to the Netscape
117      * cookie specification. The version can be changed with the 
118      * <code>setVersion</code> method.
119      *
120      *
121      * @param name 			a <code>String</code> specifying the name of the cookie
122      *
123      * @param value			a <code>String</code> specifying the value of the cookie
124      *
125      * @throws IllegalArgumentException	if the cookie name contains illegal characters
126      *					(for example, a comma, space, or semicolon)
127      *					or it is one of the tokens reserved for use
128      *					by the cookie protocol
129      * @see #setValue
130      * @see #setVersion
131      *
132      */
133 
134     public Cookie(String name, String value) {
135 	if (!isToken(name)
136 		|| name.equalsIgnoreCase("Comment")	// rfc2019
137 		|| name.equalsIgnoreCase("Discard")	// 2019++
138 		|| name.equalsIgnoreCase("Domain")
139 		|| name.equalsIgnoreCase("Expires")	// (old cookies)
140 		|| name.equalsIgnoreCase("Max-Age")	// rfc2019
141 		|| name.equalsIgnoreCase("Path")
142 		|| name.equalsIgnoreCase("Secure")
143 		|| name.equalsIgnoreCase("Version")
144 		|| name.startsWith("$")
145 	    ) {
146 	    String errMsg = lStrings.getString("err.cookie_name_is_token");
147 	    Object[] errArgs = new Object[1];
148 	    errArgs[0] = name;
149 	    errMsg = MessageFormat.format(errMsg, errArgs);
150 	    throw new IllegalArgumentException(errMsg);
151 	}
152 
153 	this.name = name;
154 	this.value = value;
155     }
156 
157 
158 
159 
160 
161     /**
162      *
163      * Specifies a comment that describes a cookie's purpose.
164      * The comment is useful if the browser presents the cookie 
165      * to the user. Comments
166      * are not supported by Netscape Version 0 cookies.
167      *
168      * @param purpose		a <code>String</code> specifying the comment 
169      *				to display to the user
170      *
171      * @see #getComment
172      *
173      */
174 
175     public void setComment(String purpose) {
176 	comment = purpose;
177     }
178     
179     
180     
181 
182     /**
183      * Returns the comment describing the purpose of this cookie, or
184      * <code>null</code> if the cookie has no comment.
185      *
186      * @return			a <code>String</code> containing the comment,
187      *				or <code>null</code> if none
188      *
189      * @see #setComment
190      *
191      */ 
192 
193     public String getComment() {
194 	return comment;
195     }
196     
197     
198     
199 
200 
201     /**
202      *
203      * Specifies the domain within which this cookie should be presented.
204      *
205      * <p>The form of the domain name is specified by RFC 2109. A domain
206      * name begins with a dot (<code>.foo.com</code>) and means that
207      * the cookie is visible to servers in a specified Domain Name System
208      * (DNS) zone (for example, <code>www.foo.com</code>, but not 
209      * <code>a.b.foo.com</code>). By default, cookies are only returned
210      * to the server that sent them.
211      *
212      *
213      * @param pattern		a <code>String</code> containing the domain name
214      *				within which this cookie is visible;
215      *				form is according to RFC 2109
216      *
217      * @see #getDomain
218      *
219      */
220 
221     public void setDomain(String pattern) {
222 	domain = pattern.toLowerCase();	// IE allegedly needs this
223     }
224     
225     
226     
227     
228 
229     /**
230      * Returns the domain name set for this cookie. The form of 
231      * the domain name is set by RFC 2109.
232      *
233      * @return			a <code>String</code> containing the domain name
234      *
235      * @see #setDomain
236      *
237      */ 
238 
239     public String getDomain() {
240 	return domain;
241     }
242 
243 
244 
245 
246     /**
247      * Sets the maximum age of the cookie in seconds.
248      *
249      * <p>A positive value indicates that the cookie will expire
250      * after that many seconds have passed. Note that the value is
251      * the <i>maximum</i> age when the cookie will expire, not the cookie's
252      * current age.
253      *
254      * <p>A negative value means
255      * that the cookie is not stored persistently and will be deleted
256      * when the Web browser exits. A zero value causes the cookie
257      * to be deleted.
258      *
259      * @param expiry		an integer specifying the maximum age of the
260      * 				cookie in seconds; if negative, means
261      *				the cookie is not stored; if zero, deletes
262      *				the cookie
263      *
264      *
265      * @see #getMaxAge
266      *
267      */
268 
269     public void setMaxAge(int expiry) {
270 	maxAge = expiry;
271     }
272 
273 
274 
275 
276     /**
277      * Returns the maximum age of the cookie, specified in seconds,
278      * By default, <code>-1</code> indicating the cookie will persist
279      * until browser shutdown.
280      *
281      *
282      * @return			an integer specifying the maximum age of the
283      *				cookie in seconds; if negative, means
284      *				the cookie persists until browser shutdown
285      *
286      *
287      * @see #setMaxAge
288      *
289      */
290 
291     public int getMaxAge() {
292 	return maxAge;
293     }
294     
295     
296     
297 
298     /**
299      * Specifies a path for the cookie
300      * to which the client should return the cookie.
301      *
302      * <p>The cookie is visible to all the pages in the directory
303      * you specify, and all the pages in that directory's subdirectories. 
304      * A cookie's path must include the servlet that set the cookie,
305      * for example, <i>/catalog</i>, which makes the cookie
306      * visible to all directories on the server under <i>/catalog</i>.
307      *
308      * <p>Consult RFC 2109 (available on the Internet) for more
309      * information on setting path names for cookies.
310      *
311      *
312      * @param uri		a <code>String</code> specifying a path
313      *
314      *
315      * @see #getPath
316      *
317      */
318 
319     public void setPath(String uri) {
320 	path = uri;
321     }
322 
323 
324 
325 
326     /**
327      * Returns the path on the server 
328      * to which the browser returns this cookie. The
329      * cookie is visible to all subpaths on the server.
330      *
331      *
332      * @return		a <code>String</code> specifying a path that contains
333      *			a servlet name, for example, <i>/catalog</i>
334      *
335      * @see #setPath
336      *
337      */ 
338 
339     public String getPath() {
340 	return path;
341     }
342 
343 
344 
345 
346 
347     /**
348      * Indicates to the browser whether the cookie should only be sent
349      * using a secure protocol, such as HTTPS or SSL.
350      *
351      * <p>The default value is <code>false</code>.
352      *
353      * @param flag	if <code>true</code>, sends the cookie from the browser
354      *			to the server only when using a secure protocol;
355      *			if <code>false</code>, sent on any protocol
356      *
357      * @see #getSecure
358      *
359      */
360  
361     public void setSecure(boolean flag) {
362 	secure = flag;
363     }
364 
365 
366 
367 
368     /**
369      * Returns <code>true</code> if the browser is sending cookies
370      * only over a secure protocol, or <code>false</code> if the
371      * browser can send cookies using any protocol.
372      *
373      * @return		<code>true</code> if the browser uses a secure protocol;
374      * 			 otherwise, <code>true</code>
375      *
376      * @see #setSecure
377      *
378      */
379 
380     public boolean getSecure() {
381 	return secure;
382     }
383 
384 
385 
386 
387 
388     /**
389      * Returns the name of the cookie. The name cannot be changed after
390      * creation.
391      *
392      * @return		a <code>String</code> specifying the cookie's name
393      *
394      */
395 
396     public String getName() {
397 	return name;
398     }
399 
400 
401 
402 
403 
404     /**
405      *
406      * Assigns a new value to a cookie after the cookie is created.
407      * If you use a binary value, you may want to use BASE64 encoding.
408      *
409      * <p>With Version 0 cookies, values should not contain white 
410      * space, brackets, parentheses, equals signs, commas,
411      * double quotes, slashes, question marks, at signs, colons,
412      * and semicolons. Empty values may not behave the same way
413      * on all browsers.
414      *
415      * @param newValue		a <code>String</code> specifying the new value 
416      *
417      *
418      * @see #getValue
419      * @see Cookie
420      *
421      */
422 
423     public void setValue(String newValue) {
424 	value = newValue;
425     }
426 
427 
428 
429 
430     /**
431      * Returns the value of the cookie.
432      *
433      * @return			a <code>String</code> containing the cookie's
434      *				present value
435      *
436      * @see #setValue
437      * @see Cookie
438      *
439      */
440 
441     public String getValue() {
442 	return value;
443     }
444 
445 
446 
447 
448     /**
449      * Returns the version of the protocol this cookie complies 
450      * with. Version 1 complies with RFC 2109, 
451      * and version 0 complies with the original
452      * cookie specification drafted by Netscape. Cookies provided
453      * by a browser use and identify the browser's cookie version.
454      * 
455      *
456      * @return			0 if the cookie complies with the
457      *				original Netscape specification; 1
458      *				if the cookie complies with RFC 2109
459      *
460      * @see #setVersion
461      *
462      */
463 
464     public int getVersion() {
465 	return version;
466     }
467 
468 
469 
470 
471     /**
472      * Sets the version of the cookie protocol this cookie complies
473      * with. Version 0 complies with the original Netscape cookie
474      * specification. Version 1 complies with RFC 2109.
475      *
476      * <p>Since RFC 2109 is still somewhat new, consider
477      * version 1 as experimental; do not use it yet on production sites.
478      *
479      *
480      * @param v			0 if the cookie should comply with 
481      *				the original Netscape specification;
482      *				1 if the cookie should comply with RFC 2109
483      *
484      * @see #getVersion
485      *
486      */
487 
488     public void setVersion(int v) {
489 	version = v;
490     }
491 
492     // Note -- disabled for now to allow full Netscape compatibility
493     // from RFC 2068, token special case characters
494     // 
495     // private static final String tspecials = "()<>@,;:\\\"/[]?={} \t";
496 
497     private static final String tspecials = ",; ";
498     
499     
500     
501 
502     /*
503      * Tests a string and returns true if the string counts as a 
504      * reserved token in the Java language.
505      * 
506      * @param value		the <code>String</code> to be tested
507      *
508      * @return			<code>true</code> if the <code>String</code> is
509      *				a reserved token; <code>false</code>
510      *				if it is not			
511      */
512 
513     private boolean isToken(String value) {
514 	int len = value.length();
515 
516 	for (int i = 0; i < len; i++) {
517 	    char c = value.charAt(i);
518 
519 	    if (c < 0x20 || c >= 0x7f || tspecials.indexOf(c) != -1)
520 		return false;
521 	}
522 	return true;
523     }
524 
525 
526 
527 
528 
529 
530     /**
531      *
532      * Overrides the standard <code>java.lang.Object.clone</code> 
533      * method to return a copy of this cookie.
534      *		
535      *
536      */
537 
538     public Object clone() {
539 	try {
540 	    return super.clone();
541 	} catch (CloneNotSupportedException e) {
542 	    throw new RuntimeException(e.getMessage());
543 	}
544     }
545 }
546