net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/flow/FinallyFlowContext.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.flow;
  12
  13 import net.sourceforge.phpdt.internal.compiler.ast.AstNode;
  14 import net.sourceforge.phpdt.internal.compiler.ast.NameReference;
  15 import net.sourceforge.phpdt.internal.compiler.ast.Reference;
  16 import net.sourceforge.phpdt.internal.compiler.lookup.BindingIds;
  17 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  18 import net.sourceforge.phpdt.internal.compiler.lookup.LocalVariableBinding;
  19 import net.sourceforge.phpdt.internal.compiler.lookup.VariableBinding;
  20
  21 /**
  22  * Reflects the context of code analysis, keeping track of enclosing
  23  *      try statements, exception handlers, etc...
  24  */
  25 public class FinallyFlowContext extends FlowContext {
  26
  27         Reference finalAssignments[];
  28         int assignCount;
  29
  30         public FinallyFlowContext(FlowContext parent, AstNode associatedNode) {
  31                 super(parent, associatedNode);
  32         }
  33
  34         /**
  35          * Given some contextual initialization info (derived from a try block or a catch block), this
  36          * code will check that the subroutine context does not also initialize a final variable potentially set
  37          * redundantly.
  38          */
  39         public void complainOnRedundantFinalAssignments(
  40                 FlowInfo flowInfo,
  41                 BlockScope scope) {
  42                 for (int i = 0; i < assignCount; i++) {
  43                         Reference ref;
  44                         if (((ref = finalAssignments[i]).bits & BindingIds.FIELD) != 0) {
  45                                 // final field
  46                                 if (flowInfo.isPotentiallyAssigned(ref.fieldBinding())) {
  47                                         scope.problemReporter().duplicateInitializationOfBlankFinalField(ref.fieldBinding(), ref);
  48                                 }
  49                         } else {
  50                                 // final local variable
  51                                 if (flowInfo
  52                                         .isPotentiallyAssigned((LocalVariableBinding) ((NameReference) ref).binding)) {
  53                                         scope.problemReporter().duplicateInitializationOfFinalLocal(
  54                                                 (LocalVariableBinding) ((NameReference) ref).binding,
  55                                                 (NameReference) ref);
  56                                 }
  57                         }
  58                         // any reference reported at this level is removed from the parent context
  59                         // where it could also be reported again
  60                         FlowContext currentContext = parent;
  61                         while (currentContext != null) {
  62                                 if (currentContext.isSubRoutine()) {
  63                                         currentContext.removeFinalAssignmentIfAny(ref);
  64                                 }
  65                                 currentContext = currentContext.parent;
  66                         }
  67                 }
  68         }
  69
  70         public boolean isSubRoutine() {
  71                 return true;
  72         }
  73
  74         boolean recordFinalAssignment(
  75                 VariableBinding binding,
  76                 Reference finalAssignment) {
  77                 if (assignCount == 0) {
  78                         finalAssignments = new Reference[5];
  79                 } else {
  80                         if (assignCount == finalAssignments.length)
  81                                 System.arraycopy(
  82                                         finalAssignments,
  83                                         0,
  84                                         (finalAssignments = new Reference[assignCount * 2]),
  85                                         0,
  86                                         assignCount);
  87                 };
  88                 finalAssignments[assignCount++] = finalAssignment;
  89                 return true;
  90         }
  91 }