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 }