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


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.StringValue;
35 import com.caucho.quercus.env.StringValueImpl;
36 import com.caucho.quercus.env.Value;
37
38 /**
39  * Converts to an string
40  */

41 public class ToStringExpr extends UnaryExpr {
42   public ToStringExpr(Location location, Expr expr)
43   {
44     super(location, expr);
45   }
46
47   public ToStringExpr(Expr expr)
48   {
49     super(expr);
50   }
51
52   public static Expr create(Expr expr)
53   {
54     if (expr.isString())
55       return expr;
56     else
57       return new ToStringExpr(expr);
58   }
59   
60   /**
61    * Evaluates the expression.
62    *
63    * @param env the calling environment.
64    *
65    * @return the expression value.
66    */

67   public Value eval(Env env)
68   {
69     Value value = _expr.eval(env).toValue();
70
71     if (value instanceof StringValue)
72       return value;
73     else
74       return new StringValueImpl(value.toString());
75   }
76
77   public String JavaDoc toString()
78   {
79     return "((string) " + _expr + ")";
80   }
81 }
82
83
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