001/*
002 * Copyright 2001 (C) MetaStuff, Ltd. All Rights Reserved.
003 * 
004 * This software is open source. 
005 * See the bottom of this file for the licence.
006 * 
007 * $Id: RuleSet.java,v 1.3 2001/08/17 09:45:19 jstrachan Exp $
008 */
009
010package org.dom4j.rule;
011
012import java.util.Collections;
013import java.util.Iterator;
014import java.util.ArrayList;
015
016import org.dom4j.Node;
017
018/** <p><code>RuleSet</code> manages a set of rules which are sorted
019  * in order of relevance according to the XSLT defined conflict
020  * resolution policy. This makes finding the correct rule for 
021  * a DOM4J Node using the XSLT processing model efficient as the
022  * rules can be evaluated in order of priority.</p>
023  *
024  * @author <a href="mailto:james.strachan@metastuff.com">James Strachan</a>
025  * @version $Revision: 1.3 $
026  */
027public class RuleSet {
028
029    /** An unordered list of Rule objects */
030    private ArrayList rules = new ArrayList();
031    
032    /** A lazily evaluated and cached array of rules sorted */
033    private Rule[] ruleArray;
034    
035    public RuleSet() {
036    }
037    
038    public String toString() {
039        return super.toString() + " [RuleSet: " + rules + " ]";
040    }
041    
042    
043    /** Performs an XSLT processing model match for the rule
044      * which matches the given Node the best.
045      *
046      * @param mode is the mode associated with the rule if any
047      * @param node is the DOM4J Node to match against
048      * @return the matching Rule or no rule if none matched
049      */
050    public Rule getMatchingRule( Node node ) {
051        Rule[] rules = getRuleArray();
052        for ( int i = rules.length - 1; i >= 0; i-- ) {
053            Rule rule = rules[i];
054            if ( rule.matches( node ) ) {
055                return rule;
056            }
057        }
058        return null;
059    }
060    
061    public void addRule(Rule rule) {
062        rules.add( rule );
063        ruleArray = null;
064    }
065    
066    public void removeRule(Rule rule) {
067        rules.remove( rule );
068        ruleArray = null;
069    }
070    
071    /** Adds all the rules to this RuleSet from the given other rule set. 
072      */
073    public void addAll(RuleSet that) {
074        rules.addAll( that.rules );
075        ruleArray = null;
076    }
077    
078    /** Returns an array of sorted rules.
079      *
080      * @return the rules as a sorted array in ascending precendence
081      * so that the rules at the end of the array should be used first
082      */
083    protected Rule[] getRuleArray() {
084        if ( ruleArray == null ) {
085            Collections.sort( rules );
086            int size = rules.size();
087            ruleArray = new Rule[ size ];
088            rules.toArray( ruleArray );
089        }
090        return ruleArray;
091    }
092
093}
094
095
096
097
098/*
099 * Redistribution and use of this software and associated documentation
100 * ("Software"), with or without modification, are permitted provided
101 * that the following conditions are met:
102 *
103 * 1. Redistributions of source code must retain copyright
104 *    statements and notices.  Redistributions must also contain a
105 *    copy of this document.
106 *
107 * 2. Redistributions in binary form must reproduce the
108 *    above copyright notice, this list of conditions and the
109 *    following disclaimer in the documentation and/or other
110 *    materials provided with the distribution.
111 *
112 * 3. The name "DOM4J" must not be used to endorse or promote
113 *    products derived from this Software without prior written
114 *    permission of MetaStuff, Ltd.  For written permission,
115 *    please contact dom4j-info@metastuff.com.
116 *
117 * 4. Products derived from this Software may not be called "DOM4J"
118 *    nor may "DOM4J" appear in their names without prior written
119 *    permission of MetaStuff, Ltd. DOM4J is a registered
120 *    trademark of MetaStuff, Ltd.
121 *
122 * 5. Due credit should be given to the DOM4J Project
123 *    (http://dom4j.org/).
124 *
125 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS
126 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
127 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
128 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
129 * METASTUFF, LTD. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
130 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
131 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
132 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
133 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
134 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
135 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
136 * OF THE POSSIBILITY OF SUCH DAMAGE.
137 *
138 * Copyright 2001 (C) MetaStuff, Ltd. All Rights Reserved.
139 *
140 * $Id: RuleSet.java,v 1.3 2001/08/17 09:45:19 jstrachan Exp $
141 */