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1   /*
2    * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
3    *
4    * This software is open source.
5    * See the bottom of this file for the licence.
6    */
7   
8   package org.dom4j.rule;
9   
10  import java.util.ArrayList;
11  import java.util.Collections;
12  
13  import org.dom4j.Node;
14  
15  /***
16   * <p>
17   * <code>RuleSet</code> manages a set of rules which are sorted in order of
18   * relevance according to the XSLT defined conflict resolution policy. This
19   * makes finding the correct rule for a DOM4J Node using the XSLT processing
20   * model efficient as the rules can be evaluated in order of priority.
21   * </p>
22   * 
23   * @author <a href="mailto:james.strachan@metastuff.com">James Strachan </a>
24   * @version $Revision: 1.10 $
25   */
26  public class RuleSet {
27      /*** An unordered list of Rule objects */
28      private ArrayList rules = new ArrayList();
29  
30      /*** A lazily evaluated and cached array of rules sorted */
31      private Rule[] ruleArray;
32  
33      public RuleSet() {
34      }
35  
36      public String toString() {
37          return super.toString() + " [RuleSet: " + rules + " ]";
38      }
39  
40      /***
41       * Performs an XSLT processing model match for the rule which matches the
42       * given Node the best.
43       * 
44       * @param node
45       *            is the DOM4J Node to match against
46       * 
47       * @return the matching Rule or no rule if none matched
48       */
49      public Rule getMatchingRule(Node node) {
50          Rule[] matches = getRuleArray();
51  
52          for (int i = matches.length - 1; i >= 0; i--) {
53              Rule rule = matches[i];
54  
55              if (rule.matches(node)) {
56                  return rule;
57              }
58          }
59  
60          return null;
61      }
62  
63      public void addRule(Rule rule) {
64          rules.add(rule);
65          ruleArray = null;
66      }
67  
68      public void removeRule(Rule rule) {
69          rules.remove(rule);
70          ruleArray = null;
71      }
72  
73      /***
74       * Adds all the rules to this RuleSet from the given other rule set.
75       * 
76       * @param that
77       *            DOCUMENT ME!
78       */
79      public void addAll(RuleSet that) {
80          rules.addAll(that.rules);
81          ruleArray = null;
82      }
83  
84      /***
85       * Returns an array of sorted rules.
86       * 
87       * @return the rules as a sorted array in ascending precendence so that the
88       *         rules at the end of the array should be used first
89       */
90      protected Rule[] getRuleArray() {
91          if (ruleArray == null) {
92              Collections.sort(rules);
93  
94              int size = rules.size();
95              ruleArray = new Rule[size];
96              rules.toArray(ruleArray);
97          }
98  
99          return ruleArray;
100     }
101 }
102 
103 /*
104  * Redistribution and use of this software and associated documentation
105  * ("Software"), with or without modification, are permitted provided that the
106  * following conditions are met:
107  * 
108  * 1. Redistributions of source code must retain copyright statements and
109  * notices. Redistributions must also contain a copy of this document.
110  * 
111  * 2. Redistributions in binary form must reproduce the above copyright notice,
112  * this list of conditions and the following disclaimer in the documentation
113  * and/or other materials provided with the distribution.
114  * 
115  * 3. The name "DOM4J" must not be used to endorse or promote products derived
116  * from this Software without prior written permission of MetaStuff, Ltd. For
117  * written permission, please contact dom4j-info@metastuff.com.
118  * 
119  * 4. Products derived from this Software may not be called "DOM4J" nor may
120  * "DOM4J" appear in their names without prior written permission of MetaStuff,
121  * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
122  * 
123  * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
124  * 
125  * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
126  * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
127  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
128  * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
129  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
130  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
131  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
132  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
133  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
134  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
135  * POSSIBILITY OF SUCH DAMAGE.
136  * 
137  * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
138  */