1 /*
2 * $Header$
3 * $Revision$
4 * $Date$
5 *
6 * ====================================================================
7 *
8 * Copyright 2000-2002 bob mcwhirter & James Strachan.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions are
13 * met:
14 *
15 * * Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 *
18 * * Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 *
22 * * Neither the name of the Jaxen Project nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
27 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
29 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
30 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
31 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
32 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
33 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
34 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
35 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
36 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 *
38 * ====================================================================
39 * This software consists of voluntary contributions made by many
40 * individuals on behalf of the Jaxen Project and was originally
41 * created by bob mcwhirter <bob@werken.com> and
42 * James Strachan <jstrachan@apache.org>. For more information on the
43 * Jaxen Project, please see <http://www.jaxen.org/>.
44 *
45 * $Id$
46 */
47
48 package org.jaxen.pattern;
49
50 import org.jaxen.Context;
51 import org.jaxen.JaxenException;
52
53 /** <p><code>Pattern</code> defines the behaviour for pattern in
54 * the XSLT processing model.</p>
55 *
56 * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
57 * @version $Revision$
58 */
59 public abstract class Pattern {
60
61 // These node numbers are compatible with both DOM and dom4j's node types
62 /** Matches Element nodes */
63 public static final short ELEMENT_NODE = 1;
64 /** Matches attribute nodes */
65 public static final short ATTRIBUTE_NODE = 2;
66 /** Matches text nodes */
67 public static final short TEXT_NODE = 3;
68 /** Matches CDATA section nodes */
69 public static final short CDATA_SECTION_NODE = 4;
70 /** Matches entity reference nodes */
71 public static final short ENTITY_REFERENCE_NODE = 5;
72 /** Matches entity nodes */
73 //public static final short ENTITY_NODE = 6;
74 /** Matches ProcessingInstruction */
75 public static final short PROCESSING_INSTRUCTION_NODE = 7;
76 /** Matches comment nodes */
77 public static final short COMMENT_NODE = 8;
78 /** Matches document nodes */
79 public static final short DOCUMENT_NODE = 9;
80 /** Matches DocumentType nodes */
81 public static final short DOCUMENT_TYPE_NODE = 10;
82 //public static final short DOCUMENT_FRAGMENT_NODE = 11;
83 //public static final short NOTATION_NODE = 12;
84
85 /** Matches a Namespace Node */
86 // This has the same value as the DOM Level 3 XPathNamespace type
87 public static final short NAMESPACE_NODE = 13;
88
89 /** Does not match any valid node */
90 public static final short UNKNOWN_NODE = 14;
91
92 /** The maximum number of node types for sizing purposes */
93 public static final short MAX_NODE_TYPE = 14;
94
95 /** Matches any node */
96 public static final short ANY_NODE = 0;
97
98 /** Matches no nodes */
99 public static final short NO_NODE = 14;
100
101
102 /**
103 *
104 * @param node ????
105 * @param context ????
106 * @return true if the pattern matches the given node
107 * @throws JaxenException if ????
108 */
109 public abstract boolean matches( Object node, Context context ) throws JaxenException;
110
111 /** Returns the default resolution policy of the pattern according to the
112 * <a href="https://www.w3.org/TR/xslt#conflict">
113 * XSLT conflict resolution rules</a>.
114 *
115 * @return 0.5; the default priority defined in XSLT
116 *
117 * @see <a href="https://www.w3.org/TR/xslt#conflict" target="_top">Section 5.5 of the XSLT specification</a>
118 *
119 */
120 public double getPriority()
121 {
122 return 0.5;
123 }
124
125 /** If this pattern is a union pattern then this
126 * method should return an array of patterns which
127 * describe the union pattern, which should contain more than one pattern.
128 * Otherwise this method should return null.
129 *
130 * @return an array of the patterns which make up this union pattern
131 * or null if this pattern is not a union pattern
132 */
133 public Pattern[] getUnionPatterns()
134 {
135 return null;
136 }
137
138
139 /**
140 * Returns the type of node the pattern matches.
141 *
142 * @return <code>ANY_NODE</code> unless overridden
143 */
144 public short getMatchType()
145 {
146 return ANY_NODE;
147 }
148
149
150 /** For patterns which only match an ATTRIBUTE_NODE or an
151 * ELEMENT_NODE then this pattern may return the name of the
152 * element or attribute it matches. This allows a more efficient
153 * rule matching algorithm to be performed, rather than a brute
154 * force approach of evaluating every pattern for a given Node.
155 *
156 * @return the name of the element or attribute this pattern matches
157 * or null if this pattern matches any or more than one name
158 */
159 public String getMatchesNodeName()
160 {
161 return null;
162 }
163
164
165 public Pattern simplify()
166 {
167 return this;
168 }
169
170 /** Returns a textual representation of this pattern
171 *
172 * @return the usual string form of this XSLT pattern
173 */
174 public abstract String getText();
175
176 }