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.ast.ASTNode;
  14 import net.sourceforge.phpdt.internal.compiler.ast.Reference;
  15 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  16 import net.sourceforge.phpdt.internal.compiler.lookup.FieldBinding;
  17 import net.sourceforge.phpdt.internal.compiler.lookup.LocalVariableBinding;
  18 import net.sourceforge.phpdt.internal.compiler.lookup.VariableBinding;
  19
  20 /**
  21  * Reflects the context of code analysis, keeping track of enclosing try
  22  * statements, exception handlers, etc...
  23  */
  24 public class FinallyFlowContext extends FlowContext {
  25
  26         Reference finalAssignments[];
  27
  28         VariableBinding finalVariables[];
  29
  30         int assignCount;
  31
  32         public FinallyFlowContext(FlowContext parent, ASTNode associatedNode) {
  33                 super(parent, associatedNode);
  34         }
  35
  36         /**
  37          * Given some contextual initialization info (derived from a try block or a
  38          * catch block), this code will check that the subroutine context does not
  39          * also initialize a final variable potentially set redundantly.
  40          */
  41         public void complainOnRedundantFinalAssignments(FlowInfo flowInfo,
  42                         BlockScope scope) {
  43                 for (int i = 0; i < assignCount; i++) {
  44                         VariableBinding variable = finalVariables[i];
  45                         if (variable == null)
  46                                 continue;
  47
  48                         boolean complained = false; // remember if have complained on this
  49                                                                                 // final assignment
  50                         if (variable instanceof FieldBinding) {
  51                                 // final field
  52                                 if (flowInfo.isPotentiallyAssigned((FieldBinding) variable)) {
  53                                         complained = true;
  54                                         scope.problemReporter()
  55                                                         .duplicateInitializationOfBlankFinalField(
  56                                                                         (FieldBinding) variable,
  57                                                                         finalAssignments[i]);
  58                                 }
  59                         } else {
  60                                 // final local variable
  61                                 if (flowInfo
  62                                                 .isPotentiallyAssigned((LocalVariableBinding) variable)) {
  63                                         complained = true;
  64                                         scope.problemReporter()
  65                                                         .duplicateInitializationOfFinalLocal(
  66                                                                         (LocalVariableBinding) variable,
  67                                                                         finalAssignments[i]);
  68                                 }
  69                         }
  70                         // any reference reported at this level is removed from the parent
  71                         // context
  72                         // where it could also be reported again
  73                         if (complained) {
  74                                 FlowContext currentContext = parent;
  75                                 while (currentContext != null) {
  76                                         // if (currentContext.isSubRoutine()) {
  77                                         currentContext
  78                                                         .removeFinalAssignmentIfAny(finalAssignments[i]);
  79                                         // }
  80                                         currentContext = currentContext.parent;
  81                                 }
  82                         }
  83                 }
  84         }
  85
  86         public String individualToString() {
  87
  88                 StringBuffer buffer = new StringBuffer("Finally flow context"); //$NON-NLS-1$
  89                 buffer
  90                                 .append("[finalAssignments count -").append(assignCount).append(']'); //$NON-NLS-1$
  91                 return buffer.toString();
  92         }
  93
  94         public boolean isSubRoutine() {
  95                 return true;
  96         }
  97
  98         boolean recordFinalAssignment(VariableBinding binding,
  99                         Reference finalAssignment) {
 100                 if (assignCount == 0) {
 101                         finalAssignments = new Reference[5];
 102                         finalVariables = new VariableBinding[5];
 103                 } else {
 104                         if (assignCount == finalAssignments.length)
 105                                 System.arraycopy(finalAssignments, 0,
 106                                                 (finalAssignments = new Reference[assignCount * 2]), 0,
 107                                                 assignCount);
 108                         System.arraycopy(finalVariables, 0,
 109                                         (finalVariables = new VariableBinding[assignCount * 2]), 0,
 110                                         assignCount);
 111                 }
 112                 ;
 113                 finalAssignments[assignCount] = finalAssignment;
 114                 finalVariables[assignCount++] = binding;
 115                 return true;
 116         }
 117
 118         void removeFinalAssignmentIfAny(Reference reference) {
 119                 for (int i = 0; i < assignCount; i++) {
 120                         if (finalAssignments[i] == reference) {
 121                                 finalAssignments[i] = null;
 122                                 finalVariables[i] = null;
 123                                 return;
 124                         }
 125                 }
 126         }
 127 }