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


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.Env;
34 import com.caucho.quercus.env.Value;
35
36 /**
37  * Represents a conditional expression.
38  */
39 public class ConditionalExpr extends Expr {
40   protected final Expr _test;
41   protected final Expr _trueExpr;
42   protected final Expr _falseExpr;
43
44   public ConditionalExpr(Location location, Expr test, Expr trueExpr, Expr falseExpr)
45   {
46     super(location);
47     _test = test;
48
49     _trueExpr = trueExpr;
50     _falseExpr = falseExpr;
51   }
52
53   public ConditionalExpr(Expr test, Expr trueExpr, Expr falseExpr)
54   {
55     _test = test;
56
57     _trueExpr = trueExpr;
58     _falseExpr = falseExpr;
59   }
60
61   /**
62    * Evaluates the expression.
63    *
64    * @param env the calling environment.
65    *
66    * @return the expression value.
67    */
68   public Value eval(Env env)
69   {
70     if (_test.evalBoolean(env))
71       return _trueExpr.eval(env);
72     else
73       return _falseExpr.eval(env);
74   }
75
76   /**
77    * Evaluates the expression.
78    *
79    * @param env the calling environment.
80    *
81    * @return the expression value.
82    */
83   public boolean evalBoolean(Env env)
84   {
85     if (_test.evalBoolean(env))
86       return _trueExpr.evalBoolean(env);
87     else
88       return _falseExpr.evalBoolean(env);
89   }
90
91   /**
92    * Evaluates the expression.
93    *
94    * @param env the calling environment.
95    *
96    * @return the expression value.
97    */
98   public Value evalCopy(Env env)
99   {
100     if (_test.evalBoolean(env))
101       return _trueExpr.evalCopy(env);
102     else
103       return _falseExpr.evalCopy(env);
104   }
105
106   public String JavaDoc toString()
107   {
108     return "(" + _test + " ? " + _trueExpr + " : " + _falseExpr + ")";
109   }
110 }
111
112
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