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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 or 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 OrOperator
69   extends BinaryOperator
70 {
71   //-------------------------------------
72
// Singleton
73
//-------------------------------------
74

75   public static final OrOperator SINGLETON =
76     new OrOperator ();
77
78   //-------------------------------------
79
/**
80    *
81    * Constructor
82    **/

83   public OrOperator ()
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 "or";
97   }
98
99   //-------------------------------------
100
/**
101    *
102    * Applies the operator to the given value
103    **/

104   public Object JavaDoc apply (Object JavaDoc pLeft,
105                Object JavaDoc pRight,
106                Logger pLogger)
107     throws ELException JavaDoc
108   {
109     // Coerce the values to booleans
110
boolean left =
111       Coercions.coerceToBoolean (pLeft, pLogger).booleanValue ();
112     boolean right =
113       Coercions.coerceToBoolean (pRight, pLogger).booleanValue ();
114
115     return PrimitiveObjects.getBoolean (left || right);
116   }
117
118   //-------------------------------------
119
/**
120    *
121    * Returns true if evaluation is necessary given the specified Left
122    * value. The And/OrOperators make use of this
123    **/

124   public boolean shouldEvaluate (Object JavaDoc pLeft)
125   {
126     return
127       (pLeft instanceof Boolean JavaDoc) &&
128       ((Boolean JavaDoc) pLeft).booleanValue () == false;
129   }
130
131   //-------------------------------------
132
/**
133    *
134    * Returns true if the operator expects its arguments to be coerced
135    * to Booleans. The And/Or operators set this to true.
136    **/

137   public boolean shouldCoerceToBoolean ()
138   {
139     return true;
140   }
141
142   //-------------------------------------
143
}
144
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