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1 /*
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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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