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


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.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.
39  */
40 public class InstanceOfExpr extends UnaryExpr {
41   protected final String JavaDoc _right;
42
43   public InstanceOfExpr(Location location, Expr left, String JavaDoc right)
44   {
45     super(location, left);
46
47     _right = right;
48   }
49
50   public InstanceOfExpr(Expr left, String JavaDoc right)
51   {
52     super(left);
53
54     _right = right;
55   }
56
57   /**
58    * Returns true for a boolean.
59    */
60   public boolean isBoolean()
61   {
62     return true;
63   }
64
65   /**
66    * Evaluates the equality as a boolean.
67    */
68   public Value eval(Env env)
69   {
70     return evalBoolean(env) ? BooleanValue.TRUE : BooleanValue.FALSE;
71   }
72
73   /**
74    * Evaluates the equality as a boolean.
75    */
76   public boolean evalBoolean(Env env)
77   {
78     Value lValue = _expr.eval(env);
79
80     return _expr.eval(env).isA(_right);
81   }
82
83   public String JavaDoc toString()
84   {
85     return "(" + _expr + " instanceof " + _right + ")";
86   }
87 }
88
89
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