Source code: org/apache/commons/el/NamedValue.java
1 /*
2 * The Apache Software License, Version 1.1
3 *
4 * Copyright (c) 1999 The Apache Software Foundation. All rights
5 * reserved.
6 *
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8 * modification, are permitted provided that the following conditions
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11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
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14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
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18 *
19 * 3. The end-user documentation included with the redistribution, if
20 * any, must include the following acknowlegement:
21 * "This product includes software developed by the
22 * Apache Software Foundation (http://www.apache.org/)."
23 * Alternately, this acknowlegement may appear in the software itself,
24 * if and wherever such third-party acknowlegements normally appear.
25 *
26 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
27 * Foundation" must not be used to endorse or promote products derived
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55
56 package org.apache.commons.el;
57
58 import javax.servlet.jsp.el.VariableResolver;
59 import javax.servlet.jsp.el.ELException;
60 import javax.servlet.jsp.el.FunctionMapper;
61
62 /**
63 *
64 * <p>Represents a name that can be used as the first element of a
65 * value.
66 *
67 * @author Nathan Abramson - Art Technology Group
68 * @author Shawn Bayern
69 * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: luehe $
70 **/
71
72 public class NamedValue
73 extends Expression
74 {
75 //-------------------------------------
76 // Constants
77 //-------------------------------------
78
79 //-------------------------------------
80 // Properties
81 //-------------------------------------
82 // property name
83
84 String mName;
85 public String getName ()
86 { return mName; }
87
88 //-------------------------------------
89 /**
90 *
91 * Constructor
92 **/
93 public NamedValue (String pName)
94 {
95 mName = pName;
96 }
97
98 //-------------------------------------
99 // Expression methods
100 //-------------------------------------
101 /**
102 *
103 * Returns the expression in the expression language syntax
104 **/
105 public String getExpressionString ()
106 {
107 return StringLiteral.toIdentifierToken (mName);
108 }
109
110 //-------------------------------------
111 /**
112 *
113 * Evaluates by looking up the name in the VariableResolver
114 **/
115 public Object evaluate (VariableResolver pResolver,
116 FunctionMapper functions,
117 Logger pLogger)
118 throws ELException
119 {
120 if (pResolver == null) {
121 return null;
122 }
123 else {
124 return pResolver.resolveVariable (mName);
125 }
126 }
127
128 //-------------------------------------
129 }