| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.codehaus.groovy.control; |
| |
| 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; |
| |
| import java.util.Iterator; |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| /** |
| * This class checks the handling of labels in the AST |
| */ |
| public class LabelVerifier extends ClassCodeVisitorSupport { |
| |
| private final SourceUnit source; |
| private LinkedList<String> visitedLabels; |
| private LinkedList<ContinueStatement> continueLabels; |
| private LinkedList<BreakStatement> breakLabels; |
| boolean inLoop = false; |
| boolean inSwitch = false; |
| |
| public LabelVerifier(SourceUnit src) { |
| source = src; |
| } |
| |
| protected SourceUnit getSourceUnit() { |
| return source; |
| } |
| |
| private void init() { |
| visitedLabels = new LinkedList<String>(); |
| continueLabels = new LinkedList<ContinueStatement>(); |
| breakLabels = new LinkedList<BreakStatement>(); |
| inLoop = false; |
| inSwitch = false; |
| } |
| |
| protected void visitClassCodeContainer(Statement code) { |
| init(); |
| super.visitClassCodeContainer(code); |
| assertNoLabelsMissed(); |
| } |
| |
| public void visitStatement(Statement statement) { |
| List<String> labels = statement.getStatementLabels(); |
| |
| if (labels != null) { |
| for (String label : labels) { |
| if (breakLabels != null) { |
| for (Iterator<BreakStatement> iter = breakLabels.iterator(); iter.hasNext(); ) { |
| if (iter.next().getLabel().equals(label)) iter.remove(); |
| } |
| } |
| if (continueLabels != null) { |
| for (Iterator<ContinueStatement> iter = continueLabels.iterator(); iter.hasNext(); ) { |
| if (iter.next().getLabel().equals(label)) iter.remove(); |
| } |
| } |
| if (visitedLabels != null) { |
| 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 (String element : visitedLabels) { |
| 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 (String element : visitedLabels) { |
| 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 (ContinueStatement element : continueLabels) { |
| addError("continue to missing label", element); |
| } |
| for (BreakStatement element : breakLabels) { |
| addError("break to missing label", element); |
| } |
| } |
| |
| public void visitSwitch(SwitchStatement statement) { |
| boolean oldInSwitch = inSwitch; |
| inSwitch = true; |
| super.visitSwitch(statement); |
| inSwitch = oldInSwitch; |
| } |
| |
| } |