001 /*
002 $Id: VariableScopeCodeVisitor.java,v 1.11 2005/04/13 11:14:22 jstrachan Exp $
003
004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005
006 Redistribution and use of this software and associated documentation
007 ("Software"), with or without modification, are permitted provided
008 that the following conditions are met:
009
010 1. Redistributions of source code must retain copyright
011 statements and notices. Redistributions must also contain a
012 copy of this document.
013
014 2. Redistributions in binary form must reproduce the
015 above copyright notice, this list of conditions and the
016 following disclaimer in the documentation and/or other
017 materials provided with the distribution.
018
019 3. The name "groovy" must not be used to endorse or promote
020 products derived from this Software without prior written
021 permission of The Codehaus. For written permission,
022 please contact info@codehaus.org.
023
024 4. Products derived from this Software may not be called "groovy"
025 nor may "groovy" appear in their names without prior written
026 permission of The Codehaus. "groovy" is a registered
027 trademark of The Codehaus.
028
029 5. Due credit should be given to The Codehaus -
030 http://groovy.codehaus.org/
031
032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043 OF THE POSSIBILITY OF SUCH DAMAGE.
044
045 */
046 package org.codehaus.groovy.classgen;
047
048 import java.util.Set;
049
050 import org.codehaus.groovy.ast.CodeVisitorSupport;
051 import org.codehaus.groovy.ast.Parameter;
052 import org.codehaus.groovy.ast.VariableScope;
053 import org.codehaus.groovy.ast.expr.BinaryExpression;
054 import org.codehaus.groovy.ast.expr.ClosureExpression;
055 import org.codehaus.groovy.ast.expr.Expression;
056 import org.codehaus.groovy.ast.expr.MethodCallExpression;
057 import org.codehaus.groovy.ast.expr.PostfixExpression;
058 import org.codehaus.groovy.ast.expr.PrefixExpression;
059 import org.codehaus.groovy.ast.expr.VariableExpression;
060 import org.codehaus.groovy.ast.stmt.ForStatement;
061
062 import org.codehaus.groovy.syntax.Types;
063
064 /**
065 * A visitor which figures out which variables are in scope
066 *
067 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
068 * @version $Revision: 1.11 $
069 */
070 public class VariableScopeCodeVisitor extends CodeVisitorSupport {
071
072 private VariableScope scope;
073
074 public VariableScopeCodeVisitor(VariableScope scope) {
075 this.scope = scope;
076 }
077
078 public Set getReferencedVariables() {
079 return scope.getReferencedVariables();
080 }
081
082 public Set getDeclaredVariables() {
083 return scope.getDeclaredVariables();
084 }
085
086
087
088 public void visitBinaryExpression(BinaryExpression expression) {
089 Expression leftExpression = expression.getLeftExpression();
090 if (expression.getOperation().isA(Types.ASSIGNMENT_OPERATOR) && leftExpression instanceof VariableExpression) {
091 declareVariable((VariableExpression) leftExpression);
092 }
093 else {
094 leftExpression.visit(this);
095 }
096 expression.getRightExpression().visit(this);
097 }
098
099 public void visitForLoop(ForStatement forLoop) {
100 declareVariable(forLoop.getVariable());
101
102 super.visitForLoop(forLoop);
103 }
104
105 public void visitClosureExpression(ClosureExpression expression) {
106 VariableScopeCodeVisitor visitor = createClosureVisitor(expression);
107 expression.getCode().visit(visitor);
108 }
109
110 public void visitVariableExpression(VariableExpression expression) {
111 // check for undeclared variables?
112 String variable = expression.getVariable();
113 /*
114 if (!parameterSet.contains(variable)) {
115 referencedVariables.add(variable);
116 }
117 */
118 getReferencedVariables().add(variable);
119 }
120
121
122 public void visitPostfixExpression(PostfixExpression expression) {
123 Expression exp = expression.getExpression();
124 if (exp instanceof VariableExpression) {
125 declareVariable((VariableExpression) exp);
126 }
127 else {
128 exp.visit(this);
129 }
130 }
131
132 public void visitPrefixExpression(PrefixExpression expression) {
133 Expression exp = expression.getExpression();
134 if (exp instanceof VariableExpression) {
135 declareVariable((VariableExpression) exp);
136 }
137 else {
138 exp.visit(this);
139 }
140 }
141
142 public void visitMethodCallExpression(MethodCallExpression call) {
143 if (call.isImplicitThis()) {
144 getReferencedVariables().add(call.getMethod());
145 }
146 super.visitMethodCallExpression(call);
147 }
148
149 public void setParameters(Parameter[] parameters) {
150 /*
151 parameterSet.clear();
152 for (int i = 0; i < parameters.length; i++) {
153 parameterSet.add(parameters[i].getName());
154 }
155 */
156
157 for (int i = 0; i < parameters.length; i++) {
158 declareVariable(parameters[i].getName());
159 }
160 }
161
162 protected void declareVariable(VariableExpression varExp) {
163 String variable = varExp.getVariable();
164 declareVariable(variable);
165 }
166
167 protected void declareVariable(String variable) {
168 /*
169 if (!parameterSet.contains(variable)) {
170 declaredVariables.add(variable);
171 getReferencedVariables().add(variable);
172 }
173 */
174 getDeclaredVariables().add(variable);
175 getReferencedVariables().add(variable);
176 }
177
178 protected VariableScopeCodeVisitor createClosureVisitor(ClosureExpression expression) {
179 VariableScope closureScope = new VariableScope(scope);
180 expression.setVariableScope(closureScope);
181 VariableScopeCodeVisitor answer = new VariableScopeCodeVisitor(closureScope);
182 answer.setParameters(expression.getParameters());
183 return answer;
184 }
185 }