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Java > Open Source Codes > com > caucho > quercus > expr > InstanceOfVarExpr


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 Nam Nguyen
28  */

29
30 package com.caucho.quercus.expr;
31
32 import com.caucho.quercus.Location;
33 import com.caucho.quercus.env.BooleanValue;
34 import com.caucho.quercus.env.Env;
35 import com.caucho.quercus.env.Value;
36
37 /**
38  * Represents a PHP instanceof expression in which the right side is a variable
39  * holding the string class name.
40  */

41 public class InstanceOfVarExpr extends BinaryExpr {
42
43   public InstanceOfVarExpr(Location location, Expr left, Expr right)
44   {
45     super(location, left, right);
46   }
47
48   public InstanceOfVarExpr(Expr left, Expr right)
49   {
50     super(left, right);
51   }
52
53   /**
54    * Returns true for a boolean.
55    */

56   public boolean isBoolean()
57   {
58     return true;
59   }
60
61   /**
62    * Evaluates the equality as a boolean.
63    */

64   public Value eval(Env env)
65   {
66     return evalBoolean(env) ? BooleanValue.TRUE : BooleanValue.FALSE;
67   }
68
69   /**
70    * Evaluates the equality as a boolean.
71    */

72   public boolean evalBoolean(Env env)
73   {
74     Value lValue = _left.eval(env);
75     Value rValue = _right.eval(env);
76
77     return lValue.isA(rValue.toString());
78   }
79
80   public String JavaDoc toString()
81   {
82     return "(" + _left + " instanceof " + _right + ")";
83   }
84 }
85
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