net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/flow/FinallyFlowContext.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 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 net.sourceforge.phpdt.internal.compiler.flow;
  12
  13 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  14 import net.sourceforge.phpdt.internal.compiler.lookup.FieldBinding;
  15 import net.sourceforge.phpdt.internal.compiler.lookup.LocalVariableBinding;
  16 import net.sourceforge.phpdt.internal.compiler.lookup.VariableBinding;
  17 import net.sourceforge.phpeclipse.internal.compiler.ast.AstNode;
  18 import net.sourceforge.phpeclipse.internal.compiler.ast.Reference;
  19
  20 /**
  21  * Reflects the context of code analysis, keeping track of enclosing
  22  *      try statements, exception handlers, etc...
  23  */
  24 public class FinallyFlowContext extends FlowContext {
  25
  26         Reference finalAssignments[];
  27         VariableBinding finalVariables[];
  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                         VariableBinding variable = finalVariables[i];
  44                         if (variable == null) continue;
  45
  46                         boolean complained = false; // remember if have complained on this final assignment
  47                         if (variable instanceof FieldBinding) {
  48                                 // final field
  49                                 if (flowInfo.isPotentiallyAssigned((FieldBinding)variable)) {
  50                                         complained = true;
  51                                         scope.problemReporter().duplicateInitializationOfBlankFinalField((FieldBinding)variable, finalAssignments[i]);
  52                                 }
  53                         } else {
  54                                 // final local variable
  55                                 if (flowInfo.isPotentiallyAssigned((LocalVariableBinding) variable)) {
  56                                         complained = true;
  57                                         scope.problemReporter().duplicateInitializationOfFinalLocal(
  58                                                 (LocalVariableBinding) variable,
  59                                                 finalAssignments[i]);
  60                                 }
  61                         }
  62                         // any reference reported at this level is removed from the parent context
  63                         // where it could also be reported again
  64                         if (complained) {
  65                                 FlowContext currentContext = parent;
  66                                 while (currentContext != null) {
  67                                         //if (currentContext.isSubRoutine()) {
  68                                         currentContext.removeFinalAssignmentIfAny(finalAssignments[i]);
  69                                         //}
  70                                         currentContext = currentContext.parent;
  71                                 }
  72                         }
  73                 }
  74         }
  75
  76         public String individualToString() {
  77
  78                 StringBuffer buffer = new StringBuffer("Finally flow context"); //$NON-NLS-1$
  79                 buffer.append("[finalAssignments count -").append(assignCount).append(']'); //$NON-NLS-1$
  80                 return buffer.toString();
  81         }
  82
  83         public boolean isSubRoutine() {
  84                 return true;
  85         }
  86
  87         boolean recordFinalAssignment(
  88                 VariableBinding binding,
  89                 Reference finalAssignment) {
  90                 if (assignCount == 0) {
  91                         finalAssignments = new Reference[5];
  92                         finalVariables = new VariableBinding[5];
  93                 } else {
  94                         if (assignCount == finalAssignments.length)
  95                                 System.arraycopy(
  96                                         finalAssignments,
  97                                         0,
  98                                         (finalAssignments = new Reference[assignCount * 2]),
  99                                         0,
 100                                         assignCount);
 101                         System.arraycopy(
 102                                 finalVariables,
 103                                 0,
 104                                 (finalVariables = new VariableBinding[assignCount * 2]),
 105                                 0,
 106                                 assignCount);
 107                 };
 108                 finalAssignments[assignCount] = finalAssignment;
 109                 finalVariables[assignCount++] = binding;
 110                 return true;
 111         }
 112
 113         void removeFinalAssignmentIfAny(Reference reference) {
 114                 for (int i = 0; i < assignCount; i++) {
 115                         if (finalAssignments[i] == reference) {
 116                                 finalAssignments[i] = null;
 117                                 finalVariables[i] = null;
 118                                 return;
 119                         }
 120                 }
 121         }
 122 }