| /* |
| $Id$ |
| |
| Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved. |
| |
| Redistribution and use of this software and associated documentation |
| ("Software"), with or without modification, are permitted provided |
| that the following conditions are met: |
| |
| 1. Redistributions of source code must retain copyright |
| statements and notices. Redistributions must also contain a |
| copy of this document. |
| |
| 2. Redistributions in binary form must reproduce the |
| above copyright notice, this list of conditions and the |
| following disclaimer in the documentation and/or other |
| materials provided with the distribution. |
| |
| 3. The name "groovy" must not be used to endorse or promote |
| products derived from this Software without prior written |
| permission of The Codehaus. For written permission, |
| please contact info@codehaus.org. |
| |
| 4. Products derived from this Software may not be called "groovy" |
| nor may "groovy" appear in their names without prior written |
| permission of The Codehaus. "groovy" is a registered |
| trademark of The Codehaus. |
| |
| 5. Due credit should be given to The Codehaus - |
| http://groovy.codehaus.org/ |
| |
| THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS |
| ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT |
| NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
| THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
| INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| */ |
| package org.codehaus.groovy.control; |
| |
| import java.util.Iterator; |
| import java.util.LinkedList; |
| |
| import org.codehaus.groovy.ast.ClassCodeVisitorSupport; |
| import org.codehaus.groovy.ast.stmt.BreakStatement; |
| import org.codehaus.groovy.ast.stmt.ContinueStatement; |
| import org.codehaus.groovy.ast.stmt.DoWhileStatement; |
| import org.codehaus.groovy.ast.stmt.ForStatement; |
| import org.codehaus.groovy.ast.stmt.Statement; |
| import org.codehaus.groovy.ast.stmt.SwitchStatement; |
| import org.codehaus.groovy.ast.stmt.WhileStatement; |
| |
| /** |
| * This class checks the handling of labels in the AST |
| * |
| * @author Jochen Theodorou |
| */ |
| public class LabelVerifier extends ClassCodeVisitorSupport { |
| |
| private SourceUnit source; |
| private LinkedList visitedLabels; |
| private LinkedList continueLabels; |
| private LinkedList breakLabels; |
| boolean inLoop=false; |
| boolean inSwitch=false; |
| |
| public LabelVerifier(SourceUnit src) { |
| source = src; |
| } |
| |
| protected SourceUnit getSourceUnit() { |
| return source; |
| } |
| |
| private void init(){ |
| visitedLabels = new LinkedList(); |
| continueLabels = new LinkedList(); |
| breakLabels = new LinkedList(); |
| inLoop=false; |
| inSwitch=false; |
| } |
| |
| protected void visitClassCodeContainer(Statement code) { |
| init(); |
| super.visitClassCodeContainer(code); |
| assertNoLabelsMissed(); |
| } |
| |
| public void visitStatement(Statement statement) { |
| String label = statement.getStatementLabel(); |
| |
| if (label!=null) { |
| for (Iterator iter = breakLabels.iterator(); iter.hasNext();) { |
| BreakStatement element = (BreakStatement) iter.next(); |
| if (element.getLabel().equals(label)) iter.remove(); |
| } |
| |
| for (Iterator iter = continueLabels.iterator(); iter.hasNext();) { |
| ContinueStatement element = (ContinueStatement) iter.next(); |
| if (element.getLabel().equals(label)) iter.remove(); |
| } |
| |
| visitedLabels.add(label); |
| } |
| |
| super.visitStatement(statement); |
| } |
| |
| public void visitForLoop(ForStatement forLoop) { |
| boolean oldInLoop = inLoop; |
| inLoop = true; |
| super.visitForLoop(forLoop); |
| inLoop = oldInLoop; |
| } |
| |
| public void visitDoWhileLoop(DoWhileStatement loop) { |
| boolean oldInLoop = inLoop; |
| inLoop = true; |
| super.visitDoWhileLoop(loop); |
| inLoop = oldInLoop; |
| } |
| |
| public void visitWhileLoop(WhileStatement loop) { |
| boolean oldInLoop = inLoop; |
| inLoop = true; |
| super.visitWhileLoop(loop); |
| inLoop = oldInLoop; |
| } |
| |
| public void visitBreakStatement(BreakStatement statement) { |
| String label = statement.getLabel(); |
| boolean hasNamedLabel = label!=null; |
| if (!hasNamedLabel && !inLoop && !inSwitch) { |
| addError("the break statement is only allowed inside loops or switches",statement); |
| } else if (hasNamedLabel && !inLoop) { |
| addError("the break statement with named label is only allowed inside loops",statement); |
| } |
| if (label!=null) { |
| boolean found=false; |
| for (Iterator iter = visitedLabels.iterator(); iter.hasNext();) { |
| String element = (String) iter.next(); |
| if (element.equals(label)) { |
| found = true; |
| break; |
| } |
| } |
| if (!found) breakLabels.add(statement); |
| } |
| |
| super.visitBreakStatement(statement); |
| } |
| |
| public void visitContinueStatement(ContinueStatement statement) { |
| String label = statement.getLabel(); |
| boolean hasNamedLabel = label!=null; |
| if (!hasNamedLabel && !inLoop) { |
| addError("the continue statement is only allowed inside loops",statement); |
| } |
| if (label!=null) { |
| boolean found=false; |
| for (Iterator iter = visitedLabels.iterator(); iter.hasNext();) { |
| String element = (String) iter.next(); |
| if (element.equals(label)) { |
| found = true; |
| break; |
| } |
| } |
| if (!found) continueLabels.add(statement); |
| } |
| |
| super.visitContinueStatement(statement); |
| } |
| |
| protected void assertNoLabelsMissed() { |
| //TODO: report multiple missing labels of the same name only once |
| for (Iterator iter = continueLabels.iterator(); iter.hasNext();) { |
| ContinueStatement element = (ContinueStatement) iter.next(); |
| addError("continue to missing label",element); |
| } |
| for (Iterator iter = breakLabels.iterator(); iter.hasNext();) { |
| BreakStatement element = (BreakStatement) iter.next(); |
| addError("break to missing label",element); |
| } |
| } |
| |
| public void visitSwitch(SwitchStatement statement) { |
| inSwitch=true; |
| super.visitSwitch(statement); |
| } |
| |
| } |