net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/ThisReference.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2001, 2002 International Business Machines Corp. and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v0.5
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v05.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  ******************************************************************************/
  11 package net.sourceforge.phpdt.internal.compiler.ast;
  12
  13 import net.sourceforge.phpdt.internal.compiler.IAbstractSyntaxTreeVisitor;
  14 import net.sourceforge.phpdt.internal.compiler.codegen.CodeStream;
  15 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  16 import net.sourceforge.phpdt.internal.compiler.lookup.MethodScope;
  17 import net.sourceforge.phpdt.internal.compiler.lookup.TypeBinding;
  18
  19 public class ThisReference extends Reference {
  20
  21         public static final ThisReference ThisImplicit = new ThisReference();
  22
  23 /**
  24  * ThisReference constructor comment.
  25  */
  26 public ThisReference() {
  27         super();
  28 }
  29 public ThisReference(int s, int sourceEnd) {
  30         this();
  31         this.sourceStart = s ;
  32         this.sourceEnd = sourceEnd;
  33 }
  34 protected boolean checkAccess(MethodScope methodScope) {
  35         // this/super cannot be used in constructor call
  36         if (methodScope.isConstructorCall) {
  37                 methodScope.problemReporter().fieldsOrThisBeforeConstructorInvocation(this);
  38                 return false;
  39         }
  40
  41         // static may not refer to this/super
  42         if (methodScope.isStatic) {
  43                 methodScope.problemReporter().errorThisSuperInStatic(this);
  44                 return false;
  45         }
  46         return true;
  47 }
  48 public void generateCode(BlockScope currentScope, CodeStream codeStream, boolean valueRequired) {
  49         int pc = codeStream.position;
  50         if (valueRequired)
  51                 codeStream.aload_0();
  52         codeStream.recordPositionsFrom(pc, this.sourceStart);
  53 }
  54 public boolean isThis() {
  55
  56         return true ;
  57 }
  58 public TypeBinding resolveType(BlockScope scope) {
  59         // implicit this
  60         constant = NotAConstant;
  61         if (this != ThisImplicit && !checkAccess(scope.methodScope()))
  62                 return null;
  63         return scope.enclosingSourceType();
  64 }
  65 public String toStringExpression(){
  66
  67         if (this == ThisImplicit) return "" ; //$NON-NLS-1$
  68         return "this"; //$NON-NLS-1$
  69 }
  70 public void traverse(IAbstractSyntaxTreeVisitor visitor, BlockScope blockScope) {
  71         visitor.visit(this, blockScope);
  72         visitor.endVisit(this, blockScope);
  73 }
  74 }