KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > caucho > xpath > pattern > FromSelf


1 /*
2  * Copyright (c) 1998-2006 Caucho Technology -- all rights reserved
3  *
4  * This file is part of Resin(R) Open Source
5  *
6  * Each copy or derived work must preserve the copyright notice and this
7  * notice unmodified.
8  *
9  * Resin Open Source is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * Resin Open Source is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17  * of NON-INFRINGEMENT. See the GNU General Public License for more
18  * details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with Resin Open Source; if not, write to the
22  * Free SoftwareFoundation, Inc.
23  * 59 Temple Place, Suite 330
24  * Boston, MA 02111-1307 USA
25  *
26  * @author Scott Ferguson
27  */
28
29 package com.caucho.xpath.pattern;
30
31 import com.caucho.xpath.Env;
32 import com.caucho.xpath.ExprEnvironment;
33 import com.caucho.xpath.XPathException;
34
35 import org.w3c.dom.Node JavaDoc;
36
37 /**
38  * The self axis matches the current node.
39  */
40 public class FromSelf extends Axis {
41   public FromSelf(AbstractPattern parent)
42   {
43     super(parent);
44   }
45   /**
46    * The self axis always matches.
47    *
48    * @param node the current node
49    * @param env the variable environment
50    *
51    * @return true
52    */
53   public boolean match(Node JavaDoc node, ExprEnvironment env)
54     throws XPathException
55   {
56     return _parent == null || _parent.match(node, env);
57   }
58
59   /**
60    * Only one node in the self axis.
61    */
62   public int position(Node JavaDoc node, Env env, AbstractPattern pattern)
63   {
64     return 1;
65   }
66
67   /**
68    * Only one node in the self axis.
69    */
70   public int count(Node JavaDoc node, Env env, AbstractPattern pattern)
71   {
72     return 1;
73   }
74
75   /**
76    * Returns the first node in the selection order.
77    *
78    * @param node the current node
79    *
80    * @return the first node
81    */
82   public Node JavaDoc firstNode(Node JavaDoc node, ExprEnvironment env)
83   {
84     return node;
85   }
86
87   /**
88    * Returns the next node in the selection order.
89    *
90    * @param node the current node
91    * @param lastNode the last node
92    *
93    * @return the next node
94    */
95   public Node JavaDoc nextNode(Node JavaDoc node, Node JavaDoc lastNode)
96   {
97     return null;
98   }
99
100   /**
101    * Returns true if the two patterns are equal.
102    */
103   public boolean equals(Object JavaDoc b)
104   {
105     if (! (b instanceof FromSelf))
106       return false;
107
108     FromSelf bPattern = (FromSelf) b;
109     
110     return (_parent == bPattern._parent ||
111             (_parent != null && _parent.equals(bPattern._parent)));
112   }
113
114   public String JavaDoc toString()
115   {
116     return getPrefix() + "self::";
117   }
118 }
119
Popular Tags