Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
SimpleFunctionContext |
|
| 2.0;2 |
1 | /* | |
2 | * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/SimpleFunctionContext.java,v 1.14 2006/02/05 21:47:41 elharo Exp $ | |
3 | * $Revision: 1.14 $ | |
4 | * $Date: 2006/02/05 21:47:41 $ | |
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: SimpleFunctionContext.java,v 1.14 2006/02/05 21:47:41 elharo Exp $ | |
46 | */ | |
47 | ||
48 | ||
49 | package org.jaxen; | |
50 | ||
51 | import java.util.HashMap; | |
52 | ||
53 | /** Simple default implementation of <code>FunctionContext</code>. | |
54 | * | |
55 | * <p> | |
56 | * This is a simple table-based key-lookup implementation | |
57 | * for <code>FunctionContext</code> which can be programmatically | |
58 | * extended by registering additional functions. | |
59 | * </p> | |
60 | * | |
61 | * @see XPathFunctionContext | |
62 | * | |
63 | * @author <a href="mailto:bob@werken.com">bob mcwhirter</a> | |
64 | */ | |
65 | public class SimpleFunctionContext implements FunctionContext | |
66 | { | |
67 | /** Table of functions. */ | |
68 | private HashMap functions; | |
69 | ||
70 | /** | |
71 | * <p> | |
72 | * Construct an empty function context. | |
73 | * </p> | |
74 | */ | |
75 | public SimpleFunctionContext() | |
76 | 106 | { |
77 | 106 | this.functions = new HashMap(); |
78 | 106 | } |
79 | ||
80 | /** Register a new function. | |
81 | * | |
82 | * <p> | |
83 | * By registering a new function, any XPath expression | |
84 | * that utilizes this <code>FunctionContext</code> may | |
85 | * refer to and use the new function. | |
86 | * </p> | |
87 | * | |
88 | * <p> | |
89 | * Functions may exist either in a namespace or not. | |
90 | * Namespace prefix-to-URI resolution is the responsibility | |
91 | * of a {@link NamespaceContext}. Within this <code>FunctionContext</code> | |
92 | * functions are only referenced using the URI, <strong>not</strong> | |
93 | * the prefix. | |
94 | * </p> | |
95 | * | |
96 | * <p> | |
97 | * The namespace URI of a function may be <code>null</code> | |
98 | * to indicate that it exists without a namespace. | |
99 | * </p> | |
100 | * | |
101 | * @param namespaceURI the namespace URI of the function to | |
102 | * be registered with this context | |
103 | * @param localName the non-prefixed local portion of the | |
104 | * function to be registered with this context | |
105 | * @param function a {@link Function} implementation object | |
106 | * to be used when evaluating the function | |
107 | */ | |
108 | public void registerFunction(String namespaceURI, | |
109 | String localName, | |
110 | Function function ) | |
111 | { | |
112 | 3384 | this.functions.put( new QualifiedName(namespaceURI, localName), |
113 | function ); | |
114 | 3384 | } |
115 | ||
116 | public Function getFunction(String namespaceURI, | |
117 | String prefix, | |
118 | String localName ) | |
119 | throws UnresolvableException | |
120 | { | |
121 | 4240 | QualifiedName key = new QualifiedName( namespaceURI, localName ); |
122 | ||
123 | 4240 | if ( this.functions.containsKey(key) ) { |
124 | 4234 | return (Function) this.functions.get( key ); |
125 | } | |
126 | else { | |
127 | 6 | throw new UnresolvableException( "No Such Function " + key.getClarkForm() ); |
128 | } | |
129 | } | |
130 | } |