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1 /*
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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.
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55
56 package org.apache.commons.el;
57
58 import javax.servlet.jsp.el.VariableResolver JavaDoc;
59 import javax.servlet.jsp.el.ELException JavaDoc;
60 import javax.servlet.jsp.el.FunctionMapper JavaDoc;
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 JavaDoc mName;
85   public String JavaDoc getName ()
86   { return mName; }
87
88   //-------------------------------------
89 /**
90    *
91    * Constructor
92    **/
93   public NamedValue (String JavaDoc 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 JavaDoc 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 JavaDoc evaluate (VariableResolver JavaDoc pResolver,
116               FunctionMapper JavaDoc functions,
117               Logger pLogger)
118     throws ELException JavaDoc
119   {
120     if (pResolver == null) {
121       return null;
122     }
123     else {
124       return pResolver.resolveVariable (mName);
125     }
126   }
127
128   //-------------------------------------
129 }
130
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