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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 import javax.servlet.jsp.el.ELException JavaDoc;
59
60 /**
61  *
62  * <p>The implementation of the and 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 AndOperator
69   extends BinaryOperator
70 {
71   //-------------------------------------
72 // Singleton
73 //-------------------------------------
74
75   public static final AndOperator SINGLETON =
76     new AndOperator ();
77
78   //-------------------------------------
79 /**
80    *
81    * Constructor
82    **/
83   public AndOperator ()
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 "and";
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 () == true;
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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