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Java > Open Source Codes > com > caucho > el > BooleanValueExpression


1 /*
2  * Copyright (c) 1998-2006 Caucho Technology -- all rights reserved
3  *
4  * This file is part of Resin(R) Open Source
5  *
6  * Each copy or derived work must preserve the copyright notice and this
7  * notice unmodified.
8  *
9  * Resin Open Source is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * Resin Open Source is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17  * of NON-INFRINGEMENT. See the GNU General Public License for more
18  * details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with Resin Open Source; if not, write to the
22  *
23  * Free Software Foundation, Inc.
24  * 59 Temple Place, Suite 330
25  * Boston, MA 02111-1307 USA
26  *
27  * @author Scott Ferguson
28  */
29
30 package com.caucho.el;
31
32 import com.caucho.util.L10N;
33
34 import javax.el.ELContext;
35 import javax.el.ELException;
36 import javax.el.PropertyNotFoundException;
37 import java.util.logging.Logger JavaDoc;
38
39 /**
40  * Abstract implementation class for an expression.
41  */
42 public class BooleanValueExpression extends AbstractValueExpression
43 {
44   protected static final Logger JavaDoc log
45     = Logger.getLogger(BooleanValueExpression.class.getName());
46   protected static final L10N L = new L10N(BooleanValueExpression.class);
47
48   private Class JavaDoc _expectedType;
49
50   public BooleanValueExpression(Expr expr,
51                 String JavaDoc expressionString,
52                 Class JavaDoc expectedType)
53   {
54     super(expr, expressionString);
55
56     _expectedType = expectedType;
57   }
58
59   public BooleanValueExpression(Expr expr,
60                 String JavaDoc expressionString)
61   {
62     super(expr, expressionString);
63   }
64
65   public BooleanValueExpression(Expr expr)
66   {
67     super(expr);
68   }
69
70   @Override JavaDoc
71   public Class JavaDoc<?> getExpectedType()
72   {
73     if (_expectedType != null)
74       return _expectedType;
75     else
76       return Boolean JavaDoc.class;
77   }
78
79   @Override JavaDoc
80   public Object JavaDoc getValue(ELContext context)
81     throws PropertyNotFoundException,
82        ELException
83   {
84     return new Boolean JavaDoc(_expr.evalBoolean(context));
85   }
86 }
87
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