KickJava   Java API By Example, From Geeks To Geeks.

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


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.NullValue;
35 import com.caucho.quercus.env.Value;
36
37 /**
38  * Represents unsetting a PHP variable
39  */
40 public class UnsetExpr extends Expr {
41   private final AbstractVarExpr _var;
42
43   public UnsetExpr(Location location, AbstractVarExpr var)
44   {
45     super(location);
46     _var = var;
47   }
48
49   public UnsetExpr(AbstractVarExpr var)
50   {
51     _var = var;
52   }
53
54   /**
55    * Evaluates the expression.
56    *
57    * @param env the calling environment.
58    *
59    * @return the expression value.
60    */
61   public Value eval(Env env)
62   {
63     _var.evalUnset(env);
64
65     return NullValue.NULL;
66   }
67
68   //
69 // Java code generation
70 //
71
72   /**
73    * Analyze the expression
74    */
75   /*
76   public void analyze(AnalyzeInfo info)
77   {
78   }
79   */
80
81   /**
82    * Generates code to evaluate the expression
83    *
84    * @param out the writer to the Java source code.
85    */
86   /*
87   public void generate(PhpWriter out)
88     throws IOException
89   {
90     String name = _var.getName();
91     
92     VarState state = _var.getVarState();
93
94     if (state == VarState.UNSET) {
95     }
96     else {
97       if (_var.getVarInfo().isGlobal()) {
98     out.print(_var.getJavaVar());
99     out.print(" = env.unsetVar(\"");
100     out.printJavaString(name);
101     out.print("\")");
102       }
103       else {
104     out.print(_var.getJavaVar());
105     out.print(" = null");
106       }
107     }
108   }
109   */
110
111   public String JavaDoc toString()
112   {
113     return "unset(" + _var + ")";
114   }
115 }
116
117
Popular Tags