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1 /*
2  * The Apache Software License, Version 1.1
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22  * Apache Software Foundation (http://www.apache.org/)."
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55
56 package org.apache.commons.el;
57
58 /**
59  *
60  * <p>An expression representing a null literal value
61  *
62  * @author Nathan Abramson - Art Technology Group
63  * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: luehe $
64  **/
65
66 public class NullLiteral
67   extends Literal
68 {
69   //-------------------------------------
70 // Member variables
71 //-------------------------------------
72
73   public static final NullLiteral SINGLETON = new NullLiteral ();
74
75   //-------------------------------------
76 /**
77    *
78    * Constructor
79    **/
80   public NullLiteral ()
81   {
82     super (null);
83   }
84
85   //-------------------------------------
86 // Expression methods
87 //-------------------------------------
88 /**
89    *
90    * Returns the expression in the expression language syntax
91    **/
92   public String JavaDoc getExpressionString ()
93   {
94     return "null";
95   }
96
97   //-------------------------------------
98 }
99
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