Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2012 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * IBM Corporation - initial API and implementation * Stephan Herrmann - Contribution for * bug 345305 - [compiler][null] Compiler misidentifies a case of "variable can only be null" *******************************************************************************/ package org.eclipse.jdt.internal.compiler.ast; import org.eclipse.jdt.internal.compiler.ASTVisitor; import org.eclipse.jdt.internal.compiler.flow.*; import org.eclipse.jdt.internal.compiler.lookup.*; public class ContinueStatement extends BranchStatement { public ContinueStatement(char[] label, int sourceStart, int sourceEnd) { super(label, sourceStart, sourceEnd); } @Override public FlowInfo analyseCode(BlockScope currentScope, FlowContext flowContext, FlowInfo flowInfo) { // here requires to generate a sequence of finally blocks invocations depending corresponding // to each of the traversed try statements, so that execution will terminate properly. // lookup the label, this should answer the returnContext FlowContext targetContext = (this.label == null) ? flowContext.getTargetContextForDefaultContinue() : flowContext.getTargetContextForContinueLabel(this.label); if (targetContext == null) { if (this.label == null) { currentScope.problemReporter().invalidContinue(this); } else { currentScope.problemReporter().undefinedLabel(this); } return flowInfo; // pretend it did not continue since no actual target } targetContext.recordAbruptExit(); targetContext.expireNullCheckedFieldInfo(); if (targetContext == FlowContext.NotContinuableContext) { currentScope.problemReporter().invalidContinue(this); return flowInfo; // pretend it did not continue since no actual target } this.initStateIndex = currentScope.methodScope().recordInitializationStates(flowInfo); this.targetLabel = targetContext.continueLabel(); FlowContext traversedContext = flowContext; int subCount = 0; this.subroutines = new SubRoutineStatement[5]; do { SubRoutineStatement sub; if ((sub = traversedContext.subroutine()) != null) { if (subCount == this.subroutines.length) { System.arraycopy(this.subroutines, 0, this.subroutines = new SubRoutineStatement[subCount * 2], 0, subCount); // grow } this.subroutines[subCount++] = sub; if (sub.isSubRoutineEscaping()) { break; } } traversedContext.recordReturnFrom(flowInfo.unconditionalInits()); if (traversedContext instanceof InsideSubRoutineFlowContext) { ASTNode node = traversedContext.associatedNode; if (node instanceof TryStatement) { TryStatement tryStatement = (TryStatement) node; flowInfo.addInitializationsFrom(tryStatement.subRoutineInits); // collect inits } } else if (traversedContext == targetContext) { // only record continue info once accumulated through subroutines, and only against target context targetContext.recordContinueFrom(flowContext, flowInfo); break; } } while ((traversedContext = traversedContext.getLocalParent()) != null); // resize subroutines if (subCount != this.subroutines.length) { System.arraycopy(this.subroutines, 0, this.subroutines = new SubRoutineStatement[subCount], 0, subCount); } return FlowInfo.DEAD_END; } @Override public StringBuffer printStatement(int tab, StringBuffer output) { printIndent(tab, output).append("continue "); //$NON-NLS-1$ if (this.label != null) output.append(this.label); return output.append(';'); } @Override public void traverse(ASTVisitor visitor, BlockScope blockScope) { visitor.visit(this, blockScope); visitor.endVisit(this, blockScope); } @Override public boolean doesNotCompleteNormally() { return true; } @Override public boolean completesByContinue() { return true; } }