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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 import javax.servlet.jsp.el.ELException JavaDoc;
59
60 /**
61  *
62  * <p>The implementation of the not operator
63  *
64  * @author Nathan Abramson - Art Technology Group
65  * @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: luehe $
66  **/
67
68 public class NotOperator
69   extends UnaryOperator
70 {
71   //-------------------------------------
72 // Singleton
73 //-------------------------------------
74
75   public static final NotOperator SINGLETON =
76     new NotOperator ();
77
78   //-------------------------------------
79 /**
80    *
81    * Constructor
82    **/
83   public NotOperator ()
84   {
85   }
86
87   //-------------------------------------
88 // Expression methods
89 //-------------------------------------
90 /**
91    *
92    * Returns the symbol representing the operator
93    **/
94   public String JavaDoc getOperatorSymbol ()
95   {
96     return "not";
97   }
98
99   //-------------------------------------
100 /**
101    *
102    * Applies the operator to the given value
103    **/
104   public Object JavaDoc apply (Object JavaDoc pValue,
105                Logger pLogger)
106     throws ELException JavaDoc
107   {
108     // Coerce the value to a boolean
109 boolean val = Coercions.coerceToBoolean (pValue, pLogger).booleanValue ();
110
111     return PrimitiveObjects.getBoolean (!val);
112   }
113
114   //-------------------------------------
115 }
116
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