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1   /*
2    * Copyright (c) 2003, 2013, 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
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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).
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25  
26  package javax.naming.ldap;
27  
28  import javax.naming.Name;
29  import javax.naming.InvalidNameException;
30  
31  import java.util.Enumeration;
32  import java.util.Collection;
33  import java.util.ArrayList;
34  import java.util.List;
35  import java.util.Iterator;
36  import java.util.ListIterator;
37  import java.util.Collections;
38  
39  import java.io.ObjectOutputStream;
40  import java.io.ObjectInputStream;
41  import java.io.IOException;
42  
43  /**
44   * This class represents a distinguished name as specified by
45   * <a href="http://www.ietf.org/rfc/rfc2253.txt">RFC 2253</a>.
46   * A distinguished name, or DN, is composed of an ordered list of
47   * components called <em>relative distinguished name</em>s, or RDNs.
48   * Details of a DN's syntax are described in RFC 2253.
49   *<p>
50   * This class resolves a few ambiguities found in RFC 2253
51   * as follows:
52   * <ul>
53   * <li> RFC 2253 leaves the term "whitespace" undefined. The
54   *      ASCII space character 0x20 (" ") is used in its place.
55   * <li> Whitespace is allowed on either side of ',', ';', '=', and '+'.
56   *      Such whitespace is accepted but not generated by this code,
57   *      and is ignored when comparing names.
58   * <li> AttributeValue strings containing '=' or non-leading '#'
59   *      characters (unescaped) are accepted.
60   * </ul>
61   *<p>
62   * String names passed to <code>LdapName</code> or returned by it
63   * use the full Unicode character set. They may also contain
64   * characters encoded into UTF-8 with each octet represented by a
65   * three-character substring such as "\\B4".
66   * They may not, however, contain characters encoded into UTF-8 with
67   * each octet represented by a single character in the string:  the
68   * meaning would be ambiguous.
69   *<p>
70   * <code>LdapName</code> will properly parse all valid names, but
71   * does not attempt to detect all possible violations when parsing
72   * invalid names.  It is "generous" in accepting invalid names.
73   * The "validity" of a name is determined ultimately when it
74   * is supplied to an LDAP server, which may accept or
75   * reject the name based on factors such as its schema information
76   * and interoperability considerations.
77   *<p>
78   * When names are tested for equality, attribute types, both binary
79   * and string values, are case-insensitive.
80   * String values with different but equivalent usage of quoting,
81   * escaping, or UTF8-hex-encoding are considered equal.  The order of
82   * components in multi-valued RDNs (such as "ou=Sales+cn=Bob") is not
83   * significant.
84   * <p>
85   * The components of a LDAP name, that is, RDNs, are numbered. The
86   * indexes of a LDAP name with n RDNs range from 0 to n-1.
87   * This range may be written as [0,n).
88   * The right most RDN is at index 0, and the left most RDN is at
89   * index n-1. For example, the distinguished name:
90   * "CN=Steve Kille, O=Isode Limited, C=GB" is numbered in the following
91   * sequence ranging from 0 to 2: {C=GB, O=Isode Limited, CN=Steve Kille}. An
92   * empty LDAP name is represented by an empty RDN list.
93   *<p>
94   * Concurrent multithreaded read-only access of an instance of
95   * <tt>LdapName</tt> need not be synchronized.
96   *<p>
97   * Unless otherwise noted, the behavior of passing a null argument
98   * to a constructor or method in this class will cause a
99   * NullPointerException to be thrown.
100  *
101  * @author Scott Seligman
102  * @since 1.5
103  */
104 
105 public class LdapName implements Name {
106 
107     private transient List<Rdn> rdns;   // parsed name components
108     private transient String unparsed;  // if non-null, the DN in unparsed form
109     private static final long serialVersionUID = -1595520034788997356L;
110 
111     /**
112      * Constructs an LDAP name from the given distinguished name.
113      *
114      * @param name  This is a non-null distinguished name formatted
115      * according to the rules defined in
116      * <a href="http://www.ietf.org/rfc/rfc2253.txt">RFC 2253</a>.
117      *
118      * @throws InvalidNameException if a syntax violation is detected.
119      * @see Rdn#escapeValue(Object value)
120      */
121     public LdapName(String name) throws InvalidNameException {
122         unparsed = name;
123         parse();
124     }
125 
126     /**
127      * Constructs an LDAP name given its parsed RDN components.
128      * <p>
129      * The indexing of RDNs in the list follows the numbering of
130      * RDNs described in the class description.
131      *
132      * @param rdns The non-null list of <tt>Rdn</tt>s forming this LDAP name.
133      */
134     public LdapName(List<Rdn> rdns) {
135 
136         // if (rdns instanceof ArrayList<Rdn>) {
137         //      this.rdns = rdns.clone();
138         // } else if (rdns instanceof List<Rdn>) {
139         //      this.rdns = new ArrayList<Rdn>(rdns);
140         // } else {
141         //      throw IllegalArgumentException(
142         //              "Invalid entries, list entries must be of type Rdn");
143         //  }
144 
145         this.rdns = new ArrayList<>(rdns.size());
146         for (int i = 0; i < rdns.size(); i++) {
147             Object obj = rdns.get(i);
148             if (!(obj instanceof Rdn)) {
149                 throw new IllegalArgumentException("Entry:" + obj +
150                         "  not a valid type;list entries must be of type Rdn");
151             }
152             this.rdns.add((Rdn)obj);
153         }
154     }
155 
156     /*
157      * Constructs an LDAP name given its parsed components (the elements
158      * of "rdns" in the range [beg,end)) and, optionally
159      * (if "name" is not null), the unparsed DN.
160      *
161      */
162     private LdapName(String name, List<Rdn> rdns, int beg, int end) {
163         unparsed = name;
164         // this.rdns = rdns.subList(beg, end);
165 
166         List<Rdn> sList = rdns.subList(beg, end);
167         this.rdns = new ArrayList<>(sList);
168     }
169 
170     /**
171      * Retrieves the number of components in this LDAP name.
172      * @return The non-negative number of components in this LDAP name.
173      */
174     public int size() {
175         return rdns.size();
176     }
177 
178     /**
179      * Determines whether this LDAP name is empty.
180      * An empty name is one with zero components.
181      * @return true if this LDAP name is empty, false otherwise.
182      */
183     public boolean isEmpty() {
184         return rdns.isEmpty();
185     }
186 
187     /**
188      * Retrieves the components of this name as an enumeration
189      * of strings. The effect of updates to this name on this enumeration
190      * is undefined. If the name has zero components, an empty (non-null)
191      * enumeration is returned.
192      * The order of the components returned by the enumeration is same as
193      * the order in which the components are numbered as described in the
194      * class description.
195      *
196      * @return A non-null enumeration of the components of this LDAP name.
197      * Each element of the enumeration is of class String.
198      */
199     public Enumeration<String> getAll() {
200         final Iterator<Rdn> iter = rdns.iterator();
201 
202         return new Enumeration<String>() {
203             public boolean hasMoreElements() {
204                 return iter.hasNext();
205             }
206             public String nextElement() {
207                 return iter.next().toString();
208             }
209         };
210     }
211 
212     /**
213      * Retrieves a component of this LDAP name as a string.
214      * @param  posn The 0-based index of the component to retrieve.
215      *              Must be in the range [0,size()).
216      * @return The non-null component at index posn.
217      * @exception IndexOutOfBoundsException if posn is outside the
218      *          specified range.
219      */
220     public String get(int posn) {
221         return rdns.get(posn).toString();
222     }
223 
224     /**
225      * Retrieves an RDN of this LDAP name as an Rdn.
226      * @param   posn The 0-based index of the RDN to retrieve.
227      *          Must be in the range [0,size()).
228      * @return The non-null RDN at index posn.
229      * @exception IndexOutOfBoundsException if posn is outside the
230      *            specified range.
231      */
232     public Rdn getRdn(int posn) {
233         return rdns.get(posn);
234     }
235 
236     /**
237      * Creates a name whose components consist of a prefix of the
238      * components of this LDAP name.
239      * Subsequent changes to this name will not affect the name
240      * that is returned and vice versa.
241      * @param  posn     The 0-based index of the component at which to stop.
242      *                  Must be in the range [0,size()].
243      * @return  An instance of <tt>LdapName</tt> consisting of the
244      *          components at indexes in the range [0,posn).
245      *          If posn is zero, an empty LDAP name is returned.
246      * @exception   IndexOutOfBoundsException
247      *              If posn is outside the specified range.
248      */
249     public Name getPrefix(int posn) {
250         try {
251             return new LdapName(null, rdns, 0, posn);
252         } catch (IllegalArgumentException e) {
253             throw new IndexOutOfBoundsException(
254                 "Posn: " + posn + ", Size: "+ rdns.size());
255         }
256     }
257 
258     /**
259      * Creates a name whose components consist of a suffix of the
260      * components in this LDAP name.
261      * Subsequent changes to this name do not affect the name that is
262      * returned and vice versa.
263      *
264      * @param  posn     The 0-based index of the component at which to start.
265      *                  Must be in the range [0,size()].
266      * @return  An instance of <tt>LdapName</tt> consisting of the
267      *          components at indexes in the range [posn,size()).
268      *          If posn is equal to size(), an empty LDAP name is
269      *          returned.
270      * @exception IndexOutOfBoundsException
271      *          If posn is outside the specified range.
272      */
273     public Name getSuffix(int posn) {
274         try {
275             return new LdapName(null, rdns, posn, rdns.size());
276         } catch (IllegalArgumentException e) {
277             throw new IndexOutOfBoundsException(
278                 "Posn: " + posn + ", Size: "+ rdns.size());
279         }
280     }
281 
282     /**
283      * Determines whether this LDAP name starts with a specified LDAP name
284      * prefix.
285      * A name <tt>n</tt> is a prefix if it is equal to
286      * <tt>getPrefix(n.size())</tt>--in other words this LDAP
287      * name starts with 'n'. If n is null or not a RFC2253 formatted name
288      * as described in the class description, false is returned.
289      *
290      * @param n The LDAP name to check.
291      * @return  true if <tt>n</tt> is a prefix of this LDAP name,
292      * false otherwise.
293      * @see #getPrefix(int posn)
294      */
295     public boolean startsWith(Name n) {
296         if (n == null) {
297             return false;
298         }
299         int len1 = rdns.size();
300         int len2 = n.size();
301         return (len1 >= len2 &&
302                 matches(0, len2, n));
303     }
304 
305     /**
306      * Determines whether the specified RDN sequence forms a prefix of this
307      * LDAP name.  Returns true if this LdapName is at least as long as rdns,
308      * and for every position p in the range [0, rdns.size()) the component
309      * getRdn(p) matches rdns.get(p). Returns false otherwise. If rdns is
310      * null, false is returned.
311      *
312      * @param rdns The sequence of <tt>Rdn</tt>s to check.
313      * @return  true if <tt>rdns</tt> form a prefix of this LDAP name,
314      *          false otherwise.
315      */
316     public boolean startsWith(List<Rdn> rdns) {
317         if (rdns == null) {
318             return false;
319         }
320         int len1 = this.rdns.size();
321         int len2 = rdns.size();
322         return (len1 >= len2 &&
323                 doesListMatch(0, len2, rdns));
324     }
325 
326     /**
327      * Determines whether this LDAP name ends with a specified
328      * LDAP name suffix.
329      * A name <tt>n</tt> is a suffix if it is equal to
330      * <tt>getSuffix(size()-n.size())</tt>--in other words this LDAP
331      * name ends with 'n'. If n is null or not a RFC2253 formatted name
332      * as described in the class description, false is returned.
333      *
334      * @param n The LDAP name to check.
335      * @return true if <tt>n</tt> is a suffix of this name, false otherwise.
336      * @see #getSuffix(int posn)
337      */
338     public boolean endsWith(Name n) {
339         if (n == null) {
340             return false;
341         }
342         int len1 = rdns.size();
343         int len2 = n.size();
344         return (len1 >= len2 &&
345                 matches(len1 - len2, len1, n));
346     }
347 
348     /**
349      * Determines whether the specified RDN sequence forms a suffix of this
350      * LDAP name.  Returns true if this LdapName is at least as long as rdns,
351      * and for every position p in the range [size() - rdns.size(), size())
352      * the component getRdn(p) matches rdns.get(p). Returns false otherwise.
353      * If rdns is null, false is returned.
354      *
355      * @param rdns The sequence of <tt>Rdn</tt>s to check.
356      * @return  true if <tt>rdns</tt> form a suffix of this LDAP name,
357      *          false otherwise.
358      */
359     public boolean endsWith(List<Rdn> rdns) {
360         if (rdns == null) {
361             return false;
362         }
363         int len1 = this.rdns.size();
364         int len2 = rdns.size();
365         return (len1 >= len2 &&
366                 doesListMatch(len1 - len2, len1, rdns));
367     }
368 
369     private boolean doesListMatch(int beg, int end, List<Rdn> rdns) {
370         for (int i = beg; i < end; i++) {
371             if (!this.rdns.get(i).equals(rdns.get(i - beg))) {
372                 return false;
373             }
374         }
375         return true;
376     }
377 
378     /*
379      * Helper method for startsWith() and endsWith().
380      * Returns true if components [beg,end) match the components of "n".
381      * If "n" is not an LdapName, each of its components is parsed as
382      * the string form of an RDN.
383      * The following must hold:  end - beg == n.size().
384      */
385     private boolean matches(int beg, int end, Name n) {
386         if (n instanceof LdapName) {
387             LdapName ln = (LdapName) n;
388             return doesListMatch(beg, end, ln.rdns);
389         } else {
390             for (int i = beg; i < end; i++) {
391                 Rdn rdn;
392                 String rdnString = n.get(i - beg);
393                 try {
394                     rdn = (new Rfc2253Parser(rdnString)).parseRdn();
395                 } catch (InvalidNameException e) {
396                     return false;
397                 }
398                 if (!rdn.equals(rdns.get(i))) {
399                     return false;
400                 }
401             }
402         }
403         return true;
404     }
405 
406     /**
407      * Adds the components of a name -- in order -- to the end of this name.
408      *
409      * @param   suffix The non-null components to add.
410      * @return  The updated name (not a new instance).
411      *
412      * @throws  InvalidNameException if <tt>suffix</tt> is not a valid LDAP
413      *          name, or if the addition of the components would violate the
414      *          syntax rules of this LDAP name.
415      */
416     public Name addAll(Name suffix) throws InvalidNameException {
417          return addAll(size(), suffix);
418     }
419 
420 
421     /**
422      * Adds the RDNs of a name -- in order -- to the end of this name.
423      *
424      * @param   suffixRdns The non-null suffix <tt>Rdn</tt>s to add.
425      * @return  The updated name (not a new instance).
426      */
427     public Name addAll(List<Rdn> suffixRdns) {
428         return addAll(size(), suffixRdns);
429     }
430 
431     /**
432      * Adds the components of a name -- in order -- at a specified position
433      * within this name. Components of this LDAP name at or after the
434      * index (if any) of the first new component are shifted up
435      * (away from index 0) to accommodate the new components.
436      *
437      * @param suffix    The non-null components to add.
438      * @param posn      The index at which to add the new component.
439      *                  Must be in the range [0,size()].
440      *
441      * @return  The updated name (not a new instance).
442      *
443      * @throws  InvalidNameException if <tt>suffix</tt> is not a valid LDAP
444      *          name, or if the addition of the components would violate the
445      *          syntax rules of this LDAP name.
446      * @throws  IndexOutOfBoundsException
447      *          If posn is outside the specified range.
448      */
449     public Name addAll(int posn, Name suffix)
450         throws InvalidNameException {
451         unparsed = null;        // no longer valid
452         if (suffix instanceof LdapName) {
453             LdapName s = (LdapName) suffix;
454             rdns.addAll(posn, s.rdns);
455         } else {
456             Enumeration<String> comps = suffix.getAll();
457             while (comps.hasMoreElements()) {
458                 rdns.add(posn++,
459                     (new Rfc2253Parser(comps.nextElement()).
460                     parseRdn()));
461             }
462         }
463         return this;
464     }
465 
466     /**
467      * Adds the RDNs of a name -- in order -- at a specified position
468      * within this name. RDNs of this LDAP name at or after the
469      * index (if any) of the first new RDN are shifted up (away from index 0) to
470      * accommodate the new RDNs.
471      *
472      * @param suffixRdns        The non-null suffix <tt>Rdn</tt>s to add.
473      * @param posn              The index at which to add the suffix RDNs.
474      *                          Must be in the range [0,size()].
475      *
476      * @return  The updated name (not a new instance).
477      * @throws  IndexOutOfBoundsException
478      *          If posn is outside the specified range.
479      */
480     public Name addAll(int posn, List<Rdn> suffixRdns) {
481         unparsed = null;
482         for (int i = 0; i < suffixRdns.size(); i++) {
483             Object obj = suffixRdns.get(i);
484             if (!(obj instanceof Rdn)) {
485                 throw new IllegalArgumentException("Entry:" + obj +
486                 "  not a valid type;suffix list entries must be of type Rdn");
487             }
488             rdns.add(i + posn, (Rdn)obj);
489         }
490         return this;
491     }
492 
493     /**
494      * Adds a single component to the end of this LDAP name.
495      *
496      * @param comp      The non-null component to add.
497      * @return          The updated LdapName, not a new instance.
498      *                  Cannot be null.
499      * @exception       InvalidNameException If adding comp at end of the name
500      *                  would violate the name's syntax.
501      */
502     public Name add(String comp) throws InvalidNameException {
503         return add(size(), comp);
504     }
505 
506     /**
507      * Adds a single RDN to the end of this LDAP name.
508      *
509      * @param comp      The non-null RDN to add.
510      *
511      * @return          The updated LdapName, not a new instance.
512      *                  Cannot be null.
513      */
514     public Name add(Rdn comp) {
515         return add(size(), comp);
516     }
517 
518     /**
519      * Adds a single component at a specified position within this
520      * LDAP name.
521      * Components of this LDAP name at or after the index (if any) of the new
522      * component are shifted up by one (away from index 0) to accommodate
523      * the new component.
524      *
525      * @param  comp     The non-null component to add.
526      * @param  posn     The index at which to add the new component.
527      *                  Must be in the range [0,size()].
528      * @return          The updated LdapName, not a new instance.
529      *                  Cannot be null.
530      * @exception       IndexOutOfBoundsException
531      *                  If posn is outside the specified range.
532      * @exception       InvalidNameException If adding comp at the
533      *                  specified position would violate the name's syntax.
534      */
535     public Name add(int posn, String comp) throws InvalidNameException {
536         Rdn rdn = (new Rfc2253Parser(comp)).parseRdn();
537         rdns.add(posn, rdn);
538         unparsed = null;        // no longer valid
539         return this;
540     }
541 
542     /**
543      * Adds a single RDN at a specified position within this
544      * LDAP name.
545      * RDNs of this LDAP name at or after the index (if any) of the new
546      * RDN are shifted up by one (away from index 0) to accommodate
547      * the new RDN.
548      *
549      * @param  comp     The non-null RDN to add.
550      * @param  posn     The index at which to add the new RDN.
551      *                  Must be in the range [0,size()].
552      * @return          The updated LdapName, not a new instance.
553      *                  Cannot be null.
554      * @exception       IndexOutOfBoundsException
555      *                  If posn is outside the specified range.
556      */
557     public Name add(int posn, Rdn comp) {
558         if (comp == null) {
559             throw new NullPointerException("Cannot set comp to null");
560         }
561         rdns.add(posn, comp);
562         unparsed = null;        // no longer valid
563         return this;
564     }
565 
566     /**
567      * Removes a component from this LDAP name.
568      * The component of this name at the specified position is removed.
569      * Components with indexes greater than this position (if any)
570      * are shifted down (toward index 0) by one.
571      *
572      * @param posn      The index of the component to remove.
573      *                  Must be in the range [0,size()).
574      * @return          The component removed (a String).
575      *
576      * @throws          IndexOutOfBoundsException
577      *                  if posn is outside the specified range.
578      * @throws          InvalidNameException if deleting the component
579      *                  would violate the syntax rules of the name.
580      */
581     public Object remove(int posn) throws InvalidNameException {
582         unparsed = null;        // no longer valid
583         return rdns.remove(posn).toString();
584     }
585 
586     /**
587      * Retrieves the list of relative distinguished names.
588      * The contents of the list are unmodifiable.
589      * The indexing of RDNs in the returned list follows the numbering of
590      * RDNs as described in the class description.
591      * If the name has zero components, an empty list is returned.
592      *
593      * @return  The name as a list of RDNs which are instances of
594      *          the class {@link Rdn Rdn}.
595      */
596     public List<Rdn> getRdns() {
597         return Collections.unmodifiableList(rdns);
598     }
599 
600     /**
601      * Generates a new copy of this name.
602      * Subsequent changes to the components of this name will not
603      * affect the new copy, and vice versa.
604      *
605      * @return A copy of the this LDAP name.
606      */
607     public Object clone() {
608         return new LdapName(unparsed, rdns, 0, rdns.size());
609     }
610 
611     /**
612      * Returns a string representation of this LDAP name in a format
613      * defined by <a href="http://www.ietf.org/rfc/rfc2253.txt">RFC 2253</a>
614      * and described in the class description. If the name has zero
615      * components an empty string is returned.
616      *
617      * @return The string representation of the LdapName.
618      */
619     public String toString() {
620         if (unparsed != null) {
621             return unparsed;
622         }
623         StringBuilder builder = new StringBuilder();
624         int size = rdns.size();
625         if ((size - 1) >= 0) {
626             builder.append(rdns.get(size - 1));
627         }
628         for (int next = size - 2; next >= 0; next--) {
629             builder.append(',');
630             builder.append(rdns.get(next));
631         }
632         unparsed = builder.toString();
633         return unparsed;
634     }
635 
636     /**
637      * Determines whether two LDAP names are equal.
638      * If obj is null or not an LDAP name, false is returned.
639      * <p>
640      * Two LDAP names are equal if each RDN in one is equal
641      * to the corresponding RDN in the other. This implies
642      * both have the same number of RDNs, and each RDN's
643      * equals() test against the corresponding RDN in the other
644      * name returns true. See {@link Rdn#equals(Object obj)}
645      * for a definition of RDN equality.
646      *
647      * @param  obj      The possibly null object to compare against.
648      * @return          true if obj is equal to this LDAP name,
649      *                  false otherwise.
650      * @see #hashCode
651      */
652     public boolean equals(Object obj) {
653         // check possible shortcuts
654         if (obj == this) {
655             return true;
656         }
657         if (!(obj instanceof LdapName)) {
658             return false;
659         }
660         LdapName that = (LdapName) obj;
661         if (rdns.size() != that.rdns.size()) {
662             return false;
663         }
664         if (unparsed != null && unparsed.equalsIgnoreCase(
665                 that.unparsed)) {
666             return true;
667         }
668         // Compare RDNs one by one for equality
669         for (int i = 0; i < rdns.size(); i++) {
670             // Compare a single pair of RDNs.
671             Rdn rdn1 = rdns.get(i);
672             Rdn rdn2 = that.rdns.get(i);
673             if (!rdn1.equals(rdn2)) {
674                 return false;
675             }
676         }
677         return true;
678     }
679 
680     /**
681      * Compares this LdapName with the specified Object for order.
682      * Returns a negative integer, zero, or a positive integer as this
683      * Name is less than, equal to, or greater than the given Object.
684      * <p>
685      * If obj is null or not an instance of LdapName, ClassCastException
686      * is thrown.
687      * <p>
688      * Ordering of LDAP names follows the lexicographical rules for
689      * string comparison, with the extension that this applies to all
690      * the RDNs in the LDAP name. All the RDNs are lined up in their
691      * specified order and compared lexicographically.
692      * See {@link Rdn#compareTo(Object obj) Rdn.compareTo(Object obj)}
693      * for RDN comparison rules.
694      * <p>
695      * If this LDAP name is lexicographically lesser than obj,
696      * a negative number is returned.
697      * If this LDAP name is lexicographically greater than obj,
698      * a positive number is returned.
699      * @param obj The non-null LdapName instance to compare against.
700      *
701      * @return  A negative integer, zero, or a positive integer as this Name
702      *          is less than, equal to, or greater than the given obj.
703      * @exception ClassCastException if obj is null or not a LdapName.
704      */
705     public int compareTo(Object obj) {
706 
707         if (!(obj instanceof LdapName)) {
708             throw new ClassCastException("The obj is not a LdapName");
709         }
710 
711         // check possible shortcuts
712         if (obj == this) {
713             return 0;
714         }
715         LdapName that = (LdapName) obj;
716 
717         if (unparsed != null && unparsed.equalsIgnoreCase(
718                         that.unparsed)) {
719             return 0;
720         }
721 
722         // Compare RDNs one by one, lexicographically.
723         int minSize = Math.min(rdns.size(), that.rdns.size());
724         for (int i = 0; i < minSize; i++) {
725             // Compare a single pair of RDNs.
726             Rdn rdn1 = rdns.get(i);
727             Rdn rdn2 = that.rdns.get(i);
728 
729             int diff = rdn1.compareTo(rdn2);
730             if (diff != 0) {
731                 return diff;
732             }
733         }
734         return (rdns.size() - that.rdns.size());        // longer DN wins
735     }
736 
737     /**
738      * Computes the hash code of this LDAP name.
739      * The hash code is the sum of the hash codes of individual RDNs
740      * of this  name.
741      *
742      * @return An int representing the hash code of this name.
743      * @see #equals
744      */
745     public int hashCode() {
746         // Sum up the hash codes of the components.
747         int hash = 0;
748 
749         // For each RDN...
750         for (int i = 0; i < rdns.size(); i++) {
751             Rdn rdn = rdns.get(i);
752             hash += rdn.hashCode();
753         }
754         return hash;
755     }
756 
757     /**
758      * Serializes only the unparsed DN, for compactness and to avoid
759      * any implementation dependency.
760      *
761      * @serialData      The DN string
762      */
763     private void writeObject(ObjectOutputStream s)
764             throws java.io.IOException {
765         s.defaultWriteObject();
766         s.writeObject(toString());
767     }
768 
769     private void readObject(ObjectInputStream s)
770             throws java.io.IOException, ClassNotFoundException {
771         s.defaultReadObject();
772         unparsed = (String)s.readObject();
773         try {
774             parse();
775         } catch (InvalidNameException e) {
776             // shouldn't happen
777             throw new java.io.StreamCorruptedException(
778                     "Invalid name: " + unparsed);
779         }
780     }
781 
782     private void parse() throws InvalidNameException {
783         // rdns = (ArrayList<Rdn>) (new RFC2253Parser(unparsed)).getDN();
784 
785         rdns = new Rfc2253Parser(unparsed).parseDn();
786     }
787 }