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1   /*
2    * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package com.sun.xml.internal.messaging.saaj.util;
27  
28  // Imported from: org.apache.xerces.util
29  // Needed to work around differences in JDK1.2 and 1.3 and deal with userInfo
30  
31  import java.io.IOException;
32  import java.io.Serializable;
33  
34  
35  /**********************************************************************
36  * A class to represent a Uniform Resource Identifier (URI). This class
37  * is designed to handle the parsing of URIs and provide access to
38  * the various components (scheme, host, port, userinfo, path, query
39  * string and fragment) that may constitute a URI.
40  * <p>
41  * Parsing of a URI specification is done according to the URI
42  * syntax described in RFC 2396
43  * <http://www.ietf.org/rfc/rfc2396.txt?number=2396>. Every URI consists
44  * of a scheme, followed by a colon (':'), followed by a scheme-specific
45  * part. For URIs that follow the "generic URI" syntax, the scheme-
46  * specific part begins with two slashes ("//") and may be followed
47  * by an authority segment (comprised of user information, host, and
48  * port), path segment, query segment and fragment. Note that RFC 2396
49  * no longer specifies the use of the parameters segment and excludes
50  * the "user:password" syntax as part of the authority segment. If
51  * "user:password" appears in a URI, the entire user/password string
52  * is stored as userinfo.
53  * <p>
54  * For URIs that do not follow the "generic URI" syntax (e.g. mailto),
55  * the entire scheme-specific part is treated as the "path" portion
56  * of the URI.
57  * <p>
58  * Note that, unlike the java.net.URL class, this class does not provide
59  * any built-in network access functionality nor does it provide any
60  * scheme-specific functionality (for example, it does not know a
61  * default port for a specific scheme). Rather, it only knows the
62  * grammar and basic set of operations that can be applied to a URI.
63  *
64  * @version
65  *
66  **********************************************************************/
67   public class JaxmURI implements Serializable {
68  
69    /*******************************************************************
70    * MalformedURIExceptions are thrown in the process of building a URI
71    * or setting fields on a URI when an operation would result in an
72    * invalid URI specification.
73    *
74    ********************************************************************/
75    public static class MalformedURIException extends IOException {
76  
77     /******************************************************************
78      * Constructs a <code>MalformedURIException</code> with no specified
79      * detail message.
80      ******************************************************************/
81      public MalformedURIException() {
82        super();
83      }
84  
85      /*****************************************************************
86      * Constructs a <code>MalformedURIException</code> with the
87      * specified detail message.
88      *
89      * @param p_msg the detail message.
90      ******************************************************************/
91      public MalformedURIException(String p_msg) {
92        super(p_msg);
93      }
94    }
95  
96    /** reserved characters */
97    private static final String RESERVED_CHARACTERS = ";/?:@&=+$,";
98  
99    /** URI punctuation mark characters - these, combined with
100       alphanumerics, constitute the "unreserved" characters */
101   private static final String MARK_CHARACTERS = "-_.!~*'() ";
102 
103   /** scheme can be composed of alphanumerics and these characters */
104   private static final String SCHEME_CHARACTERS = "+-.";
105 
106   /** userinfo can be composed of unreserved, escaped and these
107       characters */
108   private static final String USERINFO_CHARACTERS = ";:&=+$,";
109 
110   /** Stores the scheme (usually the protocol) for this URI. */
111   private String m_scheme = null;
112 
113   /** If specified, stores the userinfo for this URI; otherwise null */
114   private String m_userinfo = null;
115 
116   /** If specified, stores the host for this URI; otherwise null */
117   private String m_host = null;
118 
119   /** If specified, stores the port for this URI; otherwise -1 */
120   private int m_port = -1;
121 
122   /** If specified, stores the path for this URI; otherwise null */
123   private String m_path = null;
124 
125   /** If specified, stores the query string for this URI; otherwise
126       null.  */
127   private String m_queryString = null;
128 
129   /** If specified, stores the fragment for this URI; otherwise null */
130   private String m_fragment = null;
131 
132   private static boolean DEBUG = false;
133 
134   /**
135   * Construct a new and uninitialized URI.
136   */
137   public JaxmURI() {
138   }
139 
140  /**
141   * Construct a new URI from another URI. All fields for this URI are
142   * set equal to the fields of the URI passed in.
143   *
144   * @param p_other the URI to copy (cannot be null)
145   */
146   public JaxmURI(JaxmURI p_other) {
147     initialize(p_other);
148   }
149 
150  /**
151   * Construct a new URI from a URI specification string. If the
152   * specification follows the "generic URI" syntax, (two slashes
153   * following the first colon), the specification will be parsed
154   * accordingly - setting the scheme, userinfo, host,port, path, query
155   * string and fragment fields as necessary. If the specification does
156   * not follow the "generic URI" syntax, the specification is parsed
157   * into a scheme and scheme-specific part (stored as the path) only.
158   *
159   * @param p_uriSpec the URI specification string (cannot be null or
160   *                  empty)
161   *
162   * @exception MalformedURIException if p_uriSpec violates any syntax
163   *                                   rules
164   */
165   public JaxmURI(String p_uriSpec) throws MalformedURIException {
166     this((JaxmURI)null, p_uriSpec);
167   }
168 
169  /**
170   * Construct a new URI from a base URI and a URI specification string.
171   * The URI specification string may be a relative URI.
172   *
173   * @param p_base the base URI (cannot be null if p_uriSpec is null or
174   *               empty)
175   * @param p_uriSpec the URI specification string (cannot be null or
176   *                  empty if p_base is null)
177   *
178   * @exception MalformedURIException if p_uriSpec violates any syntax
179   *                                  rules
180   */
181   public JaxmURI(JaxmURI p_base, String p_uriSpec) throws MalformedURIException {
182     initialize(p_base, p_uriSpec);
183   }
184 
185  /**
186   * Construct a new URI that does not follow the generic URI syntax.
187   * Only the scheme and scheme-specific part (stored as the path) are
188   * initialized.
189   *
190   * @param p_scheme the URI scheme (cannot be null or empty)
191   * @param p_schemeSpecificPart the scheme-specific part (cannot be
192   *                             null or empty)
193   *
194   * @exception MalformedURIException if p_scheme violates any
195   *                                  syntax rules
196   */
197   public JaxmURI(String p_scheme, String p_schemeSpecificPart)
198              throws MalformedURIException {
199     if (p_scheme == null || p_scheme.trim().length() == 0) {
200       throw new MalformedURIException(
201             "Cannot construct URI with null/empty scheme!");
202     }
203     if (p_schemeSpecificPart == null ||
204         p_schemeSpecificPart.trim().length() == 0) {
205       throw new MalformedURIException(
206           "Cannot construct URI with null/empty scheme-specific part!");
207     }
208     setScheme(p_scheme);
209     setPath(p_schemeSpecificPart);
210   }
211 
212  /**
213   * Construct a new URI that follows the generic URI syntax from its
214   * component parts. Each component is validated for syntax and some
215   * basic semantic checks are performed as well.  See the individual
216   * setter methods for specifics.
217   *
218   * @param p_scheme the URI scheme (cannot be null or empty)
219   * @param p_host the hostname or IPv4 address for the URI
220   * @param p_path the URI path - if the path contains '?' or '#',
221   *               then the query string and/or fragment will be
222   *               set from the path; however, if the query and
223   *               fragment are specified both in the path and as
224   *               separate parameters, an exception is thrown
225   * @param p_queryString the URI query string (cannot be specified
226   *                      if path is null)
227   * @param p_fragment the URI fragment (cannot be specified if path
228   *                   is null)
229   *
230   * @exception MalformedURIException if any of the parameters violates
231   *                                  syntax rules or semantic rules
232   */
233   public JaxmURI(String p_scheme, String p_host, String p_path,
234              String p_queryString, String p_fragment)
235          throws MalformedURIException {
236     this(p_scheme, null, p_host, -1, p_path, p_queryString, p_fragment);
237   }
238 
239  /**
240   * Construct a new URI that follows the generic URI syntax from its
241   * component parts. Each component is validated for syntax and some
242   * basic semantic checks are performed as well.  See the individual
243   * setter methods for specifics.
244   *
245   * @param p_scheme the URI scheme (cannot be null or empty)
246   * @param p_userinfo the URI userinfo (cannot be specified if host
247   *                   is null)
248   * @param p_host the hostname or IPv4 address for the URI
249   * @param p_port the URI port (may be -1 for "unspecified"; cannot
250   *               be specified if host is null)
251   * @param p_path the URI path - if the path contains '?' or '#',
252   *               then the query string and/or fragment will be
253   *               set from the path; however, if the query and
254   *               fragment are specified both in the path and as
255   *               separate parameters, an exception is thrown
256   * @param p_queryString the URI query string (cannot be specified
257   *                      if path is null)
258   * @param p_fragment the URI fragment (cannot be specified if path
259   *                   is null)
260   *
261   * @exception MalformedURIException if any of the parameters violates
262   *                                  syntax rules or semantic rules
263   */
264   public JaxmURI(String p_scheme, String p_userinfo,
265              String p_host, int p_port, String p_path,
266              String p_queryString, String p_fragment)
267          throws MalformedURIException {
268     if (p_scheme == null || p_scheme.trim().length() == 0) {
269       throw new MalformedURIException("Scheme is required!");
270     }
271 
272     if (p_host == null) {
273       if (p_userinfo != null) {
274         throw new MalformedURIException(
275              "Userinfo may not be specified if host is not specified!");
276       }
277       if (p_port != -1) {
278         throw new MalformedURIException(
279              "Port may not be specified if host is not specified!");
280       }
281     }
282 
283     if (p_path != null) {
284       if (p_path.indexOf('?') != -1 && p_queryString != null) {
285         throw new MalformedURIException(
286           "Query string cannot be specified in path and query string!");
287       }
288 
289       if (p_path.indexOf('#') != -1 && p_fragment != null) {
290         throw new MalformedURIException(
291           "Fragment cannot be specified in both the path and fragment!");
292       }
293     }
294 
295     setScheme(p_scheme);
296     setHost(p_host);
297     setPort(p_port);
298     setUserinfo(p_userinfo);
299     setPath(p_path);
300     setQueryString(p_queryString);
301     setFragment(p_fragment);
302   }
303 
304  /**
305   * Initialize all fields of this URI from another URI.
306   *
307   * @param p_other the URI to copy (cannot be null)
308   */
309   private void initialize(JaxmURI p_other) {
310     m_scheme = p_other.getScheme();
311     m_userinfo = p_other.getUserinfo();
312     m_host = p_other.getHost();
313     m_port = p_other.getPort();
314     m_path = p_other.getPath();
315     m_queryString = p_other.getQueryString();
316     m_fragment = p_other.getFragment();
317   }
318 
319  /**
320   * Initializes this URI from a base URI and a URI specification string.
321   * See RFC 2396 Section 4 and Appendix B for specifications on parsing
322   * the URI and Section 5 for specifications on resolving relative URIs
323   * and relative paths.
324   *
325   * @param p_base the base URI (may be null if p_uriSpec is an absolute
326   *               URI)
327   * @param p_uriSpec the URI spec string which may be an absolute or
328   *                  relative URI (can only be null/empty if p_base
329   *                  is not null)
330   *
331   * @exception MalformedURIException if p_base is null and p_uriSpec
332   *                                  is not an absolute URI or if
333   *                                  p_uriSpec violates syntax rules
334   */
335   private void initialize(JaxmURI p_base, String p_uriSpec)
336                          throws MalformedURIException {
337     if (p_base == null &&
338         (p_uriSpec == null || p_uriSpec.trim().length() == 0)) {
339       throw new MalformedURIException(
340                   "Cannot initialize URI with empty parameters.");
341       }
342 
343     // just make a copy of the base if spec is empty
344     if (p_uriSpec == null || p_uriSpec.trim().length() == 0) {
345       initialize(p_base);
346       return;
347     }
348 
349     String uriSpec = p_uriSpec.trim();
350     int uriSpecLen = uriSpec.length();
351     int index = 0;
352 
353     // Check for scheme, which must be before `/'. Also handle names with
354     // DOS drive letters ('D:'), so 1-character schemes are not allowed.
355     int colonIdx = uriSpec.indexOf(':');
356     int slashIdx = uriSpec.indexOf('/');
357     if ((colonIdx < 2) || (colonIdx > slashIdx && slashIdx != -1)) {
358       int fragmentIdx = uriSpec.indexOf('#');
359       // A standalone base is a valid URI according to spec
360       if (p_base == null && fragmentIdx != 0 ) {
361         throw new MalformedURIException("No scheme found in URI.");
362       }
363     }
364     else {
365       initializeScheme(uriSpec);
366       index = m_scheme.length()+1;
367     }
368 
369     // two slashes means generic URI syntax, so we get the authority
370     if (((index+1) < uriSpecLen) &&
371         (uriSpec.substring(index).startsWith("//"))) {
372       index += 2;
373       int startPos = index;
374 
375       // get authority - everything up to path, query or fragment
376       char testChar = '\0';
377       while (index < uriSpecLen) {
378         testChar = uriSpec.charAt(index);
379         if (testChar == '/' || testChar == '?' || testChar == '#') {
380           break;
381         }
382         index++;
383       }
384 
385       // if we found authority, parse it out, otherwise we set the
386       // host to empty string
387       if (index > startPos) {
388         initializeAuthority(uriSpec.substring(startPos, index));
389       }
390       else {
391         m_host = "";
392       }
393     }
394 
395     initializePath(uriSpec.substring(index));
396 
397     // Resolve relative URI to base URI - see RFC 2396 Section 5.2
398     // In some cases, it might make more sense to throw an exception
399     // (when scheme is specified is the string spec and the base URI
400     // is also specified, for example), but we're just following the
401     // RFC specifications
402     if (p_base != null) {
403 
404       // check to see if this is the current doc - RFC 2396 5.2 #2
405       // note that this is slightly different from the RFC spec in that
406       // we don't include the check for query string being null
407       // - this handles cases where the urispec is just a query
408       // string or a fragment (e.g. "?y" or "#s") -
409       // see <http://www.ics.uci.edu/~fielding/url/test1.html> which
410       // identified this as a bug in the RFC
411       if (m_path.length() == 0 && m_scheme == null &&
412           m_host == null) {
413         m_scheme = p_base.getScheme();
414         m_userinfo = p_base.getUserinfo();
415         m_host = p_base.getHost();
416         m_port = p_base.getPort();
417         m_path = p_base.getPath();
418 
419         if (m_queryString == null) {
420           m_queryString = p_base.getQueryString();
421         }
422         return;
423       }
424 
425       // check for scheme - RFC 2396 5.2 #3
426       // if we found a scheme, it means absolute URI, so we're done
427       if (m_scheme == null) {
428         m_scheme = p_base.getScheme();
429       }
430       else {
431         return;
432       }
433 
434       // check for authority - RFC 2396 5.2 #4
435       // if we found a host, then we've got a network path, so we're done
436       if (m_host == null) {
437         m_userinfo = p_base.getUserinfo();
438         m_host = p_base.getHost();
439         m_port = p_base.getPort();
440       }
441       else {
442         return;
443       }
444 
445       // check for absolute path - RFC 2396 5.2 #5
446       if (m_path.length() > 0 &&
447           m_path.startsWith("/")) {
448         return;
449       }
450 
451       // if we get to this point, we need to resolve relative path
452       // RFC 2396 5.2 #6
453       String path = "";
454       String basePath = p_base.getPath();
455 
456       // 6a - get all but the last segment of the base URI path
457       if (basePath != null) {
458         int lastSlash = basePath.lastIndexOf('/');
459         if (lastSlash != -1) {
460           path = basePath.substring(0, lastSlash+1);
461         }
462       }
463 
464       // 6b - append the relative URI path
465       path = path.concat(m_path);
466 
467       // 6c - remove all "./" where "." is a complete path segment
468       index = -1;
469       while ((index = path.indexOf("/./")) != -1) {
470         path = path.substring(0, index+1).concat(path.substring(index+3));
471       }
472 
473       // 6d - remove "." if path ends with "." as a complete path segment
474       if (path.endsWith("/.")) {
475         path = path.substring(0, path.length()-1);
476       }
477 
478       // 6e - remove all "<segment>/../" where "<segment>" is a complete
479       // path segment not equal to ".."
480       index = 1;
481       int segIndex = -1;
482       String tempString = null;
483 
484       while ((index = path.indexOf("/../", index)) > 0) {
485         tempString = path.substring(0, path.indexOf("/../"));
486         segIndex = tempString.lastIndexOf('/');
487         if (segIndex != -1) {
488           if (!tempString.substring(segIndex++).equals("..")) {
489             path = path.substring(0, segIndex).concat(path.substring(index+4));
490           }
491           else
492             index += 4;
493         }
494         else
495           index += 4;
496       }
497 
498       // 6f - remove ending "<segment>/.." where "<segment>" is a
499       // complete path segment
500       if (path.endsWith("/..")) {
501         tempString = path.substring(0, path.length()-3);
502         segIndex = tempString.lastIndexOf('/');
503         if (segIndex != -1) {
504           path = path.substring(0, segIndex+1);
505         }
506       }
507       m_path = path;
508     }
509   }
510 
511  /**
512   * Initialize the scheme for this URI from a URI string spec.
513   *
514   * @param p_uriSpec the URI specification (cannot be null)
515   *
516   * @exception MalformedURIException if URI does not have a conformant
517   *                                  scheme
518   */
519   private void initializeScheme(String p_uriSpec)
520                  throws MalformedURIException {
521     int uriSpecLen = p_uriSpec.length();
522     int index = 0;
523     String scheme = null;
524     char testChar = '\0';
525 
526     while (index < uriSpecLen) {
527       testChar = p_uriSpec.charAt(index);
528       if (testChar == ':' || testChar == '/' ||
529           testChar == '?' || testChar == '#') {
530         break;
531       }
532       index++;
533     }
534     scheme = p_uriSpec.substring(0, index);
535 
536     if (scheme.length() == 0) {
537       throw new MalformedURIException("No scheme found in URI.");
538     }
539     else {
540       setScheme(scheme);
541     }
542   }
543 
544  /**
545   * Initialize the authority (userinfo, host and port) for this
546   * URI from a URI string spec.
547   *
548   * @param p_uriSpec the URI specification (cannot be null)
549   *
550   * @exception MalformedURIException if p_uriSpec violates syntax rules
551   */
552   private void initializeAuthority(String p_uriSpec)
553                  throws MalformedURIException {
554     int index = 0;
555     int start = 0;
556     int end = p_uriSpec.length();
557     char testChar = '\0';
558     String userinfo = null;
559 
560     // userinfo is everything up @
561     if (p_uriSpec.indexOf('@', start) != -1) {
562       while (index < end) {
563         testChar = p_uriSpec.charAt(index);
564         if (testChar == '@') {
565           break;
566         }
567         index++;
568       }
569       userinfo = p_uriSpec.substring(start, index);
570       index++;
571     }
572 
573     // host is everything up to ':'
574     String host = null;
575     start = index;
576     while (index < end) {
577       testChar = p_uriSpec.charAt(index);
578       if (testChar == ':') {
579         break;
580       }
581       index++;
582     }
583     host = p_uriSpec.substring(start, index);
584     int port = -1;
585     if (host.length() > 0) {
586       // port
587       if (testChar == ':') {
588         index++;
589         start = index;
590         while (index < end) {
591           index++;
592         }
593         String portStr = p_uriSpec.substring(start, index);
594         if (portStr.length() > 0) {
595           for (int i = 0; i < portStr.length(); i++) {
596             if (!isDigit(portStr.charAt(i))) {
597               throw new MalformedURIException(
598                    portStr +
599                    " is invalid. Port should only contain digits!");
600             }
601           }
602           try {
603             port = Integer.parseInt(portStr);
604           }
605           catch (NumberFormatException nfe) {
606             // can't happen
607           }
608         }
609       }
610     }
611     setHost(host);
612     setPort(port);
613     setUserinfo(userinfo);
614   }
615 
616  /**
617   * Initialize the path for this URI from a URI string spec.
618   *
619   * @param p_uriSpec the URI specification (cannot be null)
620   *
621   * @exception MalformedURIException if p_uriSpec violates syntax rules
622   */
623   private void initializePath(String p_uriSpec)
624                  throws MalformedURIException {
625     if (p_uriSpec == null) {
626       throw new MalformedURIException(
627                 "Cannot initialize path from null string!");
628     }
629 
630     int index = 0;
631     int start = 0;
632     int end = p_uriSpec.length();
633     char testChar = '\0';
634 
635     // path - everything up to query string or fragment
636     while (index < end) {
637       testChar = p_uriSpec.charAt(index);
638       if (testChar == '?' || testChar == '#') {
639         break;
640       }
641       // check for valid escape sequence
642       if (testChar == '%') {
643          if (index+2 >= end ||
644             !isHex(p_uriSpec.charAt(index+1)) ||
645             !isHex(p_uriSpec.charAt(index+2))) {
646           throw new MalformedURIException(
647                 "Path contains invalid escape sequence!");
648          }
649       }
650       else if (!isReservedCharacter(testChar) &&
651                !isUnreservedCharacter(testChar)) {
652         throw new MalformedURIException(
653                   "Path contains invalid character: " + testChar);
654       }
655       index++;
656     }
657     m_path = p_uriSpec.substring(start, index);
658 
659     // query - starts with ? and up to fragment or end
660     if (testChar == '?') {
661       index++;
662       start = index;
663       while (index < end) {
664         testChar = p_uriSpec.charAt(index);
665         if (testChar == '#') {
666           break;
667         }
668         if (testChar == '%') {
669            if (index+2 >= end ||
670               !isHex(p_uriSpec.charAt(index+1)) ||
671               !isHex(p_uriSpec.charAt(index+2))) {
672             throw new MalformedURIException(
673                     "Query string contains invalid escape sequence!");
674            }
675         }
676         else if (!isReservedCharacter(testChar) &&
677                  !isUnreservedCharacter(testChar)) {
678           throw new MalformedURIException(
679                 "Query string contains invalid character:" + testChar);
680         }
681         index++;
682       }
683       m_queryString = p_uriSpec.substring(start, index);
684     }
685 
686     // fragment - starts with #
687     if (testChar == '#') {
688       index++;
689       start = index;
690       while (index < end) {
691         testChar = p_uriSpec.charAt(index);
692 
693         if (testChar == '%') {
694            if (index+2 >= end ||
695               !isHex(p_uriSpec.charAt(index+1)) ||
696               !isHex(p_uriSpec.charAt(index+2))) {
697             throw new MalformedURIException(
698                     "Fragment contains invalid escape sequence!");
699            }
700         }
701         else if (!isReservedCharacter(testChar) &&
702                  !isUnreservedCharacter(testChar)) {
703           throw new MalformedURIException(
704                 "Fragment contains invalid character:"+testChar);
705         }
706         index++;
707       }
708       m_fragment = p_uriSpec.substring(start, index);
709     }
710   }
711 
712  /**
713   * Get the scheme for this URI.
714   *
715   * @return the scheme for this URI
716   */
717   public String getScheme() {
718     return m_scheme;
719   }
720 
721  /**
722   * Get the scheme-specific part for this URI (everything following the
723   * scheme and the first colon). See RFC 2396 Section 5.2 for spec.
724   *
725   * @return the scheme-specific part for this URI
726   */
727   public String getSchemeSpecificPart() {
728     StringBuffer schemespec = new StringBuffer();
729 
730     if (m_userinfo != null || m_host != null || m_port != -1) {
731       schemespec.append("//");
732     }
733 
734     if (m_userinfo != null) {
735       schemespec.append(m_userinfo);
736       schemespec.append('@');
737     }
738 
739     if (m_host != null) {
740       schemespec.append(m_host);
741     }
742 
743     if (m_port != -1) {
744       schemespec.append(':');
745       schemespec.append(m_port);
746     }
747 
748     if (m_path != null) {
749       schemespec.append((m_path));
750     }
751 
752     if (m_queryString != null) {
753       schemespec.append('?');
754       schemespec.append(m_queryString);
755     }
756 
757     if (m_fragment != null) {
758       schemespec.append('#');
759       schemespec.append(m_fragment);
760     }
761 
762     return schemespec.toString();
763   }
764 
765  /**
766   * Get the userinfo for this URI.
767   *
768   * @return the userinfo for this URI (null if not specified).
769   */
770   public String getUserinfo() {
771     return m_userinfo;
772   }
773 
774   /**
775   * Get the host for this URI.
776   *
777   * @return the host for this URI (null if not specified).
778   */
779   public String getHost() {
780     return m_host;
781   }
782 
783  /**
784   * Get the port for this URI.
785   *
786   * @return the port for this URI (-1 if not specified).
787   */
788   public int getPort() {
789     return m_port;
790   }
791 
792  /**
793   * Get the path for this URI (optionally with the query string and
794   * fragment).
795   *
796   * @param p_includeQueryString if true (and query string is not null),
797   *                             then a "?" followed by the query string
798   *                             will be appended
799   * @param p_includeFragment if true (and fragment is not null),
800   *                             then a "#" followed by the fragment
801   *                             will be appended
802   *
803   * @return the path for this URI possibly including the query string
804   *         and fragment
805   */
806   public String getPath(boolean p_includeQueryString,
807                         boolean p_includeFragment) {
808     StringBuffer pathString = new StringBuffer(m_path);
809 
810     if (p_includeQueryString && m_queryString != null) {
811       pathString.append('?');
812       pathString.append(m_queryString);
813     }
814 
815     if (p_includeFragment && m_fragment != null) {
816       pathString.append('#');
817       pathString.append(m_fragment);
818     }
819     return pathString.toString();
820   }
821 
822  /**
823   * Get the path for this URI. Note that the value returned is the path
824   * only and does not include the query string or fragment.
825   *
826   * @return the path for this URI.
827   */
828   public String getPath() {
829     return m_path;
830   }
831 
832  /**
833   * Get the query string for this URI.
834   *
835   * @return the query string for this URI. Null is returned if there
836   *         was no "?" in the URI spec, empty string if there was a
837   *         "?" but no query string following it.
838   */
839   public String getQueryString() {
840     return m_queryString;
841   }
842 
843  /**
844   * Get the fragment for this URI.
845   *
846   * @return the fragment for this URI. Null is returned if there
847   *         was no "#" in the URI spec, empty string if there was a
848   *         "#" but no fragment following it.
849   */
850   public String getFragment() {
851     return m_fragment;
852   }
853 
854  /**
855   * Set the scheme for this URI. The scheme is converted to lowercase
856   * before it is set.
857   *
858   * @param p_scheme the scheme for this URI (cannot be null)
859   *
860   * @exception MalformedURIException if p_scheme is not a conformant
861   *                                  scheme name
862   */
863   public void setScheme(String p_scheme) throws MalformedURIException {
864     if (p_scheme == null) {
865       throw new MalformedURIException(
866                 "Cannot set scheme from null string!");
867     }
868     if (!isConformantSchemeName(p_scheme)) {
869       throw new MalformedURIException("The scheme is not conformant.");
870     }
871 
872     m_scheme = p_scheme.toLowerCase();
873   }
874 
875  /**
876   * Set the userinfo for this URI. If a non-null value is passed in and
877   * the host value is null, then an exception is thrown.
878   *
879   * @param p_userinfo the userinfo for this URI
880   *
881   * @exception MalformedURIException if p_userinfo contains invalid
882   *                                  characters
883   */
884   public void setUserinfo(String p_userinfo) throws MalformedURIException {
885     if (p_userinfo == null) {
886       m_userinfo = null;
887     }
888     else {
889       if (m_host == null) {
890         throw new MalformedURIException(
891                      "Userinfo cannot be set when host is null!");
892       }
893 
894       // userinfo can contain alphanumerics, mark characters, escaped
895       // and ';',':','&','=','+','$',','
896       int index = 0;
897       int end = p_userinfo.length();
898       char testChar = '\0';
899       while (index < end) {
900         testChar = p_userinfo.charAt(index);
901         if (testChar == '%') {
902           if (index+2 >= end ||
903               !isHex(p_userinfo.charAt(index+1)) ||
904               !isHex(p_userinfo.charAt(index+2))) {
905             throw new MalformedURIException(
906                   "Userinfo contains invalid escape sequence!");
907           }
908         }
909         else if (!isUnreservedCharacter(testChar) &&
910                  USERINFO_CHARACTERS.indexOf(testChar) == -1) {
911           throw new MalformedURIException(
912                   "Userinfo contains invalid character:"+testChar);
913         }
914         index++;
915       }
916     }
917     m_userinfo = p_userinfo;
918   }
919 
920   /**
921   * Set the host for this URI. If null is passed in, the userinfo
922   * field is also set to null and the port is set to -1.
923   *
924   * @param p_host the host for this URI
925   *
926   * @exception MalformedURIException if p_host is not a valid IP
927   *                                  address or DNS hostname.
928   */
929   public void setHost(String p_host) throws MalformedURIException {
930     if (p_host == null || p_host.trim().length() == 0) {
931       m_host = p_host;
932       m_userinfo = null;
933       m_port = -1;
934     }
935     else if (!isWellFormedAddress(p_host)) {
936       throw new MalformedURIException("Host is not a well formed address!");
937     }
938     m_host = p_host;
939   }
940 
941  /**
942   * Set the port for this URI. -1 is used to indicate that the port is
943   * not specified, otherwise valid port numbers are  between 0 and 65535.
944   * If a valid port number is passed in and the host field is null,
945   * an exception is thrown.
946   *
947   * @param p_port the port number for this URI
948   *
949   * @exception MalformedURIException if p_port is not -1 and not a
950   *                                  valid port number
951   */
952   public void setPort(int p_port) throws MalformedURIException {
953     if (p_port >= 0 && p_port <= 65535) {
954       if (m_host == null) {
955         throw new MalformedURIException(
956                       "Port cannot be set when host is null!");
957       }
958     }
959     else if (p_port != -1) {
960       throw new MalformedURIException("Invalid port number!");
961     }
962     m_port = p_port;
963   }
964 
965  /**
966   * Set the path for this URI. If the supplied path is null, then the
967   * query string and fragment are set to null as well. If the supplied
968   * path includes a query string and/or fragment, these fields will be
969   * parsed and set as well. Note that, for URIs following the "generic
970   * URI" syntax, the path specified should start with a slash.
971   * For URIs that do not follow the generic URI syntax, this method
972   * sets the scheme-specific part.
973   *
974   * @param p_path the path for this URI (may be null)
975   *
976   * @exception MalformedURIException if p_path contains invalid
977   *                                  characters
978   */
979   public void setPath(String p_path) throws MalformedURIException {
980     if (p_path == null) {
981       m_path = null;
982       m_queryString = null;
983       m_fragment = null;
984     }
985     else {
986       initializePath(p_path);
987     }
988   }
989 
990  /**
991   * Append to the end of the path of this URI. If the current path does
992   * not end in a slash and the path to be appended does not begin with
993   * a slash, a slash will be appended to the current path before the
994   * new segment is added. Also, if the current path ends in a slash
995   * and the new segment begins with a slash, the extra slash will be
996   * removed before the new segment is appended.
997   *
998   * @param p_addToPath the new segment to be added to the current path
999   *
1000   * @exception MalformedURIException if p_addToPath contains syntax
1001   *                                  errors
1002   */
1003   public void appendPath(String p_addToPath)
1004                          throws MalformedURIException {
1005     if (p_addToPath == null || p_addToPath.trim().length() == 0) {
1006       return;
1007     }
1008 
1009     if (!isURIString(p_addToPath)) {
1010       throw new MalformedURIException(
1011               "Path contains invalid character!");
1012     }
1013 
1014     if (m_path == null || m_path.trim().length() == 0) {
1015       if (p_addToPath.startsWith("/")) {
1016         m_path = p_addToPath;
1017       }
1018       else {
1019         m_path = "/" + p_addToPath;
1020       }
1021     }
1022     else if (m_path.endsWith("/")) {
1023       if (p_addToPath.startsWith("/")) {
1024         m_path = m_path.concat(p_addToPath.substring(1));
1025       }
1026       else {
1027         m_path = m_path.concat(p_addToPath);
1028       }
1029     }
1030     else {
1031       if (p_addToPath.startsWith("/")) {
1032         m_path = m_path.concat(p_addToPath);
1033       }
1034       else {
1035         m_path = m_path.concat("/" + p_addToPath);
1036       }
1037     }
1038   }
1039 
1040  /**
1041   * Set the query string for this URI. A non-null value is valid only
1042   * if this is an URI conforming to the generic URI syntax and
1043   * the path value is not null.
1044   *
1045   * @param p_queryString the query string for this URI
1046   *
1047   * @exception MalformedURIException if p_queryString is not null and this
1048   *                                  URI does not conform to the generic
1049   *                                  URI syntax or if the path is null
1050   */
1051   public void setQueryString(String p_queryString) throws MalformedURIException {
1052     if (p_queryString == null) {
1053       m_queryString = null;
1054     }
1055     else if (!isGenericURI()) {
1056       throw new MalformedURIException(
1057               "Query string can only be set for a generic URI!");
1058     }
1059     else if (getPath() == null) {
1060       throw new MalformedURIException(
1061               "Query string cannot be set when path is null!");
1062     }
1063     else if (!isURIString(p_queryString)) {
1064       throw new MalformedURIException(
1065               "Query string contains invalid character!");
1066     }
1067     else {
1068       m_queryString = p_queryString;
1069     }
1070   }
1071 
1072  /**
1073   * Set the fragment for this URI. A non-null value is valid only
1074   * if this is a URI conforming to the generic URI syntax and
1075   * the path value is not null.
1076   *
1077   * @param p_fragment the fragment for this URI
1078   *
1079   * @exception MalformedURIException if p_fragment is not null and this
1080   *                                  URI does not conform to the generic
1081   *                                  URI syntax or if the path is null
1082   */
1083   public void setFragment(String p_fragment) throws MalformedURIException {
1084     if (p_fragment == null) {
1085       m_fragment = null;
1086     }
1087     else if (!isGenericURI()) {
1088       throw new MalformedURIException(
1089          "Fragment can only be set for a generic URI!");
1090     }
1091     else if (getPath() == null) {
1092       throw new MalformedURIException(
1093               "Fragment cannot be set when path is null!");
1094     }
1095     else if (!isURIString(p_fragment)) {
1096       throw new MalformedURIException(
1097               "Fragment contains invalid character!");
1098     }
1099     else {
1100       m_fragment = p_fragment;
1101     }
1102   }
1103 
1104  /**
1105   * Determines if the passed-in Object is equivalent to this URI.
1106   *
1107   * @param p_test the Object to test for equality.
1108   *
1109   * @return true if p_test is a URI with all values equal to this
1110   *         URI, false otherwise
1111   */
1112   public boolean equals(Object p_test) {
1113     if (p_test instanceof JaxmURI) {
1114       JaxmURI testURI = (JaxmURI) p_test;
1115       if (((m_scheme == null && testURI.m_scheme == null) ||
1116            (m_scheme != null && testURI.m_scheme != null &&
1117             m_scheme.equals(testURI.m_scheme))) &&
1118           ((m_userinfo == null && testURI.m_userinfo == null) ||
1119            (m_userinfo != null && testURI.m_userinfo != null &&
1120             m_userinfo.equals(testURI.m_userinfo))) &&
1121           ((m_host == null && testURI.m_host == null) ||
1122            (m_host != null && testURI.m_host != null &&
1123             m_host.equals(testURI.m_host))) &&
1124             m_port == testURI.m_port &&
1125           ((m_path == null && testURI.m_path == null) ||
1126            (m_path != null && testURI.m_path != null &&
1127             m_path.equals(testURI.m_path))) &&
1128           ((m_queryString == null && testURI.m_queryString == null) ||
1129            (m_queryString != null && testURI.m_queryString != null &&
1130             m_queryString.equals(testURI.m_queryString))) &&
1131           ((m_fragment == null && testURI.m_fragment == null) ||
1132            (m_fragment != null && testURI.m_fragment != null &&
1133             m_fragment.equals(testURI.m_fragment)))) {
1134         return true;
1135       }
1136     }
1137     return false;
1138   }
1139 
1140   public int hashCode() {
1141           // No members safe to use, just default to a constant.
1142           return 153214;
1143   }
1144 
1145  /**
1146   * Get the URI as a string specification. See RFC 2396 Section 5.2.
1147   *
1148   * @return the URI string specification
1149   */
1150   public String toString() {
1151     StringBuffer uriSpecString = new StringBuffer();
1152 
1153     if (m_scheme != null) {
1154       uriSpecString.append(m_scheme);
1155       uriSpecString.append(':');
1156     }
1157     uriSpecString.append(getSchemeSpecificPart());
1158     return uriSpecString.toString();
1159   }
1160 
1161  /**
1162   * Get the indicator as to whether this URI uses the "generic URI"
1163   * syntax.
1164   *
1165   * @return true if this URI uses the "generic URI" syntax, false
1166   *         otherwise
1167   */
1168   public boolean isGenericURI() {
1169     // presence of the host (whether valid or empty) means
1170     // double-slashes which means generic uri
1171     return (m_host != null);
1172   }
1173 
1174  /**
1175   * Determine whether a scheme conforms to the rules for a scheme name.
1176   * A scheme is conformant if it starts with an alphanumeric, and
1177   * contains only alphanumerics, '+','-' and '.'.
1178   *
1179   * @return true if the scheme is conformant, false otherwise
1180   */
1181   public static boolean isConformantSchemeName(String p_scheme) {
1182     if (p_scheme == null || p_scheme.trim().length() == 0) {
1183       return false;
1184     }
1185 
1186     if (!isAlpha(p_scheme.charAt(0))) {
1187       return false;
1188     }
1189 
1190     char testChar;
1191     for (int i = 1; i < p_scheme.length(); i++) {
1192       testChar = p_scheme.charAt(i);
1193       if (!isAlphanum(testChar) &&
1194           SCHEME_CHARACTERS.indexOf(testChar) == -1) {
1195         return false;
1196       }
1197     }
1198 
1199     return true;
1200   }
1201 
1202  /**
1203   * Determine whether a string is syntactically capable of representing
1204   * a valid IPv4 address or the domain name of a network host. A valid
1205   * IPv4 address consists of four decimal digit groups separated by a
1206   * '.'. A hostname consists of domain labels (each of which must
1207   * begin and end with an alphanumeric but may contain '-') separated
1208   & by a '.'. See RFC 2396 Section 3.2.2.
1209   *
1210   * @return true if the string is a syntactically valid IPv4 address
1211   *              or hostname
1212   */
1213   public static boolean isWellFormedAddress(String p_address) {
1214     if (p_address == null) {
1215       return false;
1216     }
1217 
1218     String address = p_address.trim();
1219     int addrLength = address.length();
1220     if (addrLength == 0 || addrLength > 255) {
1221       return false;
1222     }
1223 
1224     if (address.startsWith(".") || address.startsWith("-")) {
1225       return false;
1226     }
1227 
1228     // rightmost domain label starting with digit indicates IP address
1229     // since top level domain label can only start with an alpha
1230     // see RFC 2396 Section 3.2.2
1231     int index = address.lastIndexOf('.');
1232     if (address.endsWith(".")) {
1233       index = address.substring(0, index).lastIndexOf('.');
1234     }
1235 
1236     if (index+1 < addrLength && isDigit(p_address.charAt(index+1))) {
1237       char testChar;
1238       int numDots = 0;
1239 
1240       // make sure that 1) we see only digits and dot separators, 2) that
1241       // any dot separator is preceded and followed by a digit and
1242       // 3) that we find 3 dots
1243       for (int i = 0; i < addrLength; i++) {
1244         testChar = address.charAt(i);
1245         if (testChar == '.') {
1246           if (!isDigit(address.charAt(i-1)) ||
1247               (i+1 < addrLength && !isDigit(address.charAt(i+1)))) {
1248             return false;
1249           }
1250           numDots++;
1251         }
1252         else if (!isDigit(testChar)) {
1253           return false;
1254         }
1255       }
1256       if (numDots != 3) {
1257         return false;
1258       }
1259     }
1260     else {
1261       // domain labels can contain alphanumerics and '-"
1262       // but must start and end with an alphanumeric
1263       char testChar;
1264 
1265       for (int i = 0; i < addrLength; i++) {
1266         testChar = address.charAt(i);
1267         if (testChar == '.') {
1268           if (!isAlphanum(address.charAt(i-1))) {
1269             return false;
1270           }
1271           if (i+1 < addrLength && !isAlphanum(address.charAt(i+1))) {
1272             return false;
1273           }
1274         }
1275         else if (!isAlphanum(testChar) && testChar != '-') {
1276           return false;
1277         }
1278       }
1279     }
1280     return true;
1281   }
1282 
1283 
1284  /**
1285   * Determine whether a char is a digit.
1286   *
1287   * @return true if the char is betweeen '0' and '9', false otherwise
1288   */
1289   private static boolean isDigit(char p_char) {
1290     return p_char >= '0' && p_char <= '9';
1291   }
1292 
1293  /**
1294   * Determine whether a character is a hexadecimal character.
1295   *
1296   * @return true if the char is betweeen '0' and '9', 'a' and 'f'
1297   *         or 'A' and 'F', false otherwise
1298   */
1299   private static boolean isHex(char p_char) {
1300     return (isDigit(p_char) ||
1301             (p_char >= 'a' && p_char <= 'f') ||
1302             (p_char >= 'A' && p_char <= 'F'));
1303   }
1304 
1305  /**
1306   * Determine whether a char is an alphabetic character: a-z or A-Z
1307   *
1308   * @return true if the char is alphabetic, false otherwise
1309   */
1310   private static boolean isAlpha(char p_char) {
1311     return ((p_char >= 'a' && p_char <= 'z') ||
1312             (p_char >= 'A' && p_char <= 'Z' ));
1313   }
1314 
1315  /**
1316   * Determine whether a char is an alphanumeric: 0-9, a-z or A-Z
1317   *
1318   * @return true if the char is alphanumeric, false otherwise
1319   */
1320   private static boolean isAlphanum(char p_char) {
1321     return (isAlpha(p_char) || isDigit(p_char));
1322   }
1323 
1324  /**
1325   * Determine whether a character is a reserved character:
1326   * ';', '/', '?', ':', '@', '&', '=', '+', '$' or ','
1327   *
1328   * @return true if the string contains any reserved characters
1329   */
1330   private static boolean isReservedCharacter(char p_char) {
1331     return RESERVED_CHARACTERS.indexOf(p_char) != -1;
1332   }
1333 
1334  /**
1335   * Determine whether a char is an unreserved character.
1336   *
1337   * @return true if the char is unreserved, false otherwise
1338   */
1339   private static boolean isUnreservedCharacter(char p_char) {
1340     return (isAlphanum(p_char) ||
1341             MARK_CHARACTERS.indexOf(p_char) != -1);
1342   }
1343 
1344  /**
1345   * Determine whether a given string contains only URI characters (also
1346   * called "uric" in RFC 2396). uric consist of all reserved
1347   * characters, unreserved characters and escaped characters.
1348   *
1349   * @return true if the string is comprised of uric, false otherwise
1350   */
1351   private static boolean isURIString(String p_uric) {
1352     if (p_uric == null) {
1353       return false;
1354     }
1355     int end = p_uric.length();
1356     char testChar = '\0';
1357     for (int i = 0; i < end; i++) {
1358       testChar = p_uric.charAt(i);
1359       if (testChar == '%') {
1360         if (i+2 >= end ||
1361             !isHex(p_uric.charAt(i+1)) ||
1362             !isHex(p_uric.charAt(i+2))) {
1363           return false;
1364         }
1365         else {
1366           i += 2;
1367           continue;
1368         }
1369       }
1370       if (isReservedCharacter(testChar) ||
1371           isUnreservedCharacter(testChar)) {
1372           continue;
1373       }
1374       else {
1375         return false;
1376       }
1377     }
1378     return true;
1379   }
1380 }