src/org/eclipse/jdt/internal/compiler/ast/EmptyStatement.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2004 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package org.eclipse.jdt.internal.compiler.ast;
  12
  13 import org.eclipse.jdt.internal.compiler.lookup.BlockScope;
  14 import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants;
  15 import org.eclipse.jdt.internal.compiler.codegen.CodeStream;
  16 import org.eclipse.jdt.internal.compiler.flow.FlowContext;
  17 import org.eclipse.jdt.internal.compiler.flow.FlowInfo;
  18 import org.eclipse.jdt.internal.compiler.ASTVisitor;
  19
  20 public class EmptyStatement extends Statement {
  21
  22         public EmptyStatement(int startPosition, int endPosition) {
  23                 this.sourceStart = startPosition;
  24                 this.sourceEnd = endPosition;
  25         }
  26
  27         public FlowInfo analyseCode(BlockScope currentScope, FlowContext flowContext, FlowInfo flowInfo) {
  28                 return flowInfo;
  29         }
  30
  31         // Report an error if necessary
  32         public boolean complainIfUnreachable(FlowInfo flowInfo, BlockScope scope, boolean didAlreadyComplain) {
  33
  34                 // before 1.4, empty statements are tolerated anywhere
  35                 if (scope.environment().options.complianceLevel < ClassFileConstants.JDK1_4) {
  36                         return false;
  37                 }
  38                 return super.complainIfUnreachable(flowInfo, scope, didAlreadyComplain);
  39         }
  40
  41         public void generateCode(BlockScope currentScope, CodeStream codeStream){
  42                 // no bytecode, no need to check for reachability or recording source positions
  43         }
  44
  45         public StringBuffer printStatement(int tab, StringBuffer output) {
  46                 return printIndent(tab, output).append(';');
  47         }
  48
  49         public void resolve(BlockScope scope) {
  50                 if ((bits & IsUsefulEmptyStatementMASK) == 0) {
  51                         scope.problemReporter().superfluousSemicolon(this.sourceStart, this.sourceEnd);
  52                 } else {
  53                         scope.problemReporter().emptyControlFlowStatement(this.sourceStart, this.sourceEnd);
  54                 }
  55         }
  56
  57         public void traverse(ASTVisitor visitor, BlockScope scope) {
  58                 visitor.visit(this, scope);
  59                 visitor.endVisit(this, scope);
  60         }
  61
  62
  63 }
  64