Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
Predicate |
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| 1.0;1 |
1 | /* | |
2 | * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/expr/Predicate.java,v 1.14 2007/05/02 14:27:46 elharo Exp $ | |
3 | * $Revision: 1.14 $ | |
4 | * $Date: 2007/05/02 14:27:46 $ | |
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: Predicate.java,v 1.14 2007/05/02 14:27:46 elharo Exp $ | |
46 | */ | |
47 | ||
48 | ||
49 | ||
50 | package org.jaxen.expr; | |
51 | ||
52 | import java.io.Serializable; | |
53 | import org.jaxen.Context; | |
54 | import org.jaxen.JaxenException; | |
55 | ||
56 | ||
57 | /** | |
58 | * Represents an XPath predicate such as <code>[position() = last()]</code>. | |
59 | * This is production 8 and 9 in the | |
60 | * <a href="http://www.w3.org/TR/xpath#NT-Predicate">XPath 1.0 specification</a>: | |
61 | * | |
62 | * <pre> [8] Predicate ::= '[' PredicateExpr ']' | |
63 | * [9] PredicateExpr ::= Expr</pre> | |
64 | * | |
65 | */ | |
66 | public interface Predicate extends Serializable | |
67 | { | |
68 | /** | |
69 | * Returns the expression in this predicate. | |
70 | * | |
71 | * @return the expression between the brackets | |
72 | */ | |
73 | Expr getExpr(); | |
74 | ||
75 | /** | |
76 | * Change the expression used by this predicate. | |
77 | * | |
78 | * @param expr the new expression | |
79 | */ | |
80 | void setExpr(Expr expr); | |
81 | ||
82 | /** | |
83 | * Simplify the expression in this predicate. | |
84 | * | |
85 | * @see Expr#simplify() | |
86 | */ | |
87 | void simplify(); | |
88 | ||
89 | /** | |
90 | * Returns the string form of the predicate, | |
91 | * including the square brackets. | |
92 | * | |
93 | * @return the bracketed form of this predicate | |
94 | */ | |
95 | String getText(); | |
96 | ||
97 | /** | |
98 | * Evaluates this predicate's expression and returns the result. | |
99 | * The result will be a <code>java.lang.Double</code> for expressions that | |
100 | * return a number, a <code>java.lang.String</code> for expressions that | |
101 | * return a string, a <code>java.lang.Boolean</code> for expressions that | |
102 | * return a boolean, and a <code>java.util.List</code> for expressions that | |
103 | * return a node-set. In the latter case, the elements of the list are | |
104 | * the actual objects from the source document model. Copies are not made. | |
105 | * | |
106 | * @param context the context in which the expression is evaluated | |
107 | * @return an object representing the result of the evaluation | |
108 | * @throws JaxenException | |
109 | * @see Expr#evaluate(Context) | |
110 | */ | |
111 | Object evaluate(Context context) throws JaxenException; | |
112 | ||
113 | } |