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1   /*
2    $Id: VariableExpression.java,v 1.14 2006/01/19 00:06:51 blackdrag Exp $
3   
4    Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
5   
6    Redistribution and use of this software and associated documentation
7    ("Software"), with or without modification, are permitted provided
8    that the following conditions are met:
9   
10   1. Redistributions of source code must retain copyright
11      statements and notices.  Redistributions must also contain a
12      copy of this document.
13  
14   2. Redistributions in binary form must reproduce the
15      above copyright notice, this list of conditions and the
16      following disclaimer in the documentation and/or other
17      materials provided with the distribution.
18  
19   3. The name "groovy" must not be used to endorse or promote
20      products derived from this Software without prior written
21      permission of The Codehaus.  For written permission,
22      please contact info@codehaus.org.
23  
24   4. Products derived from this Software may not be called "groovy"
25      nor may "groovy" appear in their names without prior written
26      permission of The Codehaus. "groovy" is a registered
27      trademark of The Codehaus.
28  
29   5. Due credit should be given to The Codehaus -
30      http://groovy.codehaus.org/
31  
32   THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
33   ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
34   NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
35   FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
36   THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39   SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41   STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43   OF THE POSSIBILITY OF SUCH DAMAGE.
44  
45   */
46  package org.codehaus.groovy.ast.expr;
47  
48  import org.codehaus.groovy.ast.ClassHelper;
49  import org.codehaus.groovy.ast.ClassNode;
50  import org.codehaus.groovy.ast.GroovyCodeVisitor;
51  import org.codehaus.groovy.ast.Variable;
52  
53  /***
54   * Represents a local variable name, the simplest form of expression. e.g. "foo".
55   * 
56   * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
57   * @version $Revision: 1.14 $
58   */
59  public class VariableExpression extends Expression implements Variable {
60  
61      public static final VariableExpression THIS_EXPRESSION = new VariableExpression("this", ClassHelper.DYNAMIC_TYPE);
62      public static final VariableExpression SUPER_EXPRESSION = new VariableExpression("super", ClassHelper.DYNAMIC_TYPE);
63  
64      private String variable;
65      private boolean inStaticContext;
66      private boolean isDynamicTyped=false;
67      private Variable accessedVariable;
68      boolean closureShare=false;
69  
70      public Variable getAccessedVariable() {
71          return accessedVariable;
72      }
73  
74      public void setAccessedVariable(Variable origin) {
75          this.accessedVariable = origin;
76      }
77  
78      public VariableExpression(String variable, ClassNode type) {
79          this.variable = variable;
80          super.setType(ClassHelper.getWrapper(type));
81      }
82      
83      public VariableExpression(String variable) {
84          this(variable, ClassHelper.DYNAMIC_TYPE);
85      }
86      
87      public VariableExpression(Variable variable) {
88          this(variable.getName(), variable.getType());
89          setAccessedVariable(variable);
90      }
91  
92      public void visit(GroovyCodeVisitor visitor) {
93          visitor.visitVariableExpression(this);
94      }
95  
96      public Expression transformExpression(ExpressionTransformer transformer) {
97          return this;
98      }
99  
100     public String getText() {
101         return variable;
102     }
103     
104     public String getName() {
105         return variable;
106     }
107 
108     /***
109      * @return true if this variable is dynamically typed
110      */
111     public String toString() {
112         return super.toString() + "[variable: " + variable + (this.isDynamicTyped() ? "" : " type: " + getType()) + "]";
113     }
114 
115     public Expression getInitialExpression() {
116         return null;
117     }
118 
119     public boolean hasInitialExpression() {
120         return false;
121     }
122     
123     public boolean isInStaticContext() {
124         if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isInStaticContext();
125         return inStaticContext;
126     }
127     
128     public void setInStaticContext(boolean inStaticContext) {
129         this.inStaticContext = inStaticContext;
130     }
131 
132     public void setType(ClassNode cn){
133         super.setType(cn);
134         isDynamicTyped |= ClassHelper.DYNAMIC_TYPE==cn;
135     }
136     
137     public boolean isDynamicTyped() {
138         return isDynamicTyped;
139     }
140 
141     public boolean isClosureSharedVariable() {
142         if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.isClosureSharedVariable();
143         return closureShare;
144     }
145     
146     public void setClosureSharedVariable(boolean inClosure) {
147         closureShare = inClosure;        
148     }
149     
150     public ClassNode getType() {
151         if (accessedVariable!=null && accessedVariable!=this) return accessedVariable.getType();
152         return super.getType();
153     }
154 }