Esempio n. 1
0
  /**
   * The confluence operator is essentially the union of all of the inItems. However, if two or more
   * of the initCount maps from the inItems each have a MinMaxInitCounts entry for the same
   * VarInstance, the conflict must be resolved, by using the minimum of all mins and the maximum of
   * all maxs.
   */
  public Item confluence(List inItems, Term node, FlowGraph graph) {
    // Resolve any conflicts pairwise.
    Iterator iter = inItems.iterator();
    Map m = null;
    while (iter.hasNext()) {
      Item itm = (Item) iter.next();
      if (itm == BOTTOM) continue;
      if (m == null) {
        m = new HashMap(((DataFlowItem) itm).initStatus);
      } else {
        Map n = ((DataFlowItem) itm).initStatus;
        for (Iterator iter2 = n.entrySet().iterator(); iter2.hasNext(); ) {
          Map.Entry entry = (Map.Entry) iter2.next();
          VarInstance v = (VarInstance) entry.getKey();
          MinMaxInitCount initCount1 = (MinMaxInitCount) m.get(v);
          MinMaxInitCount initCount2 = (MinMaxInitCount) entry.getValue();
          m.put(v, MinMaxInitCount.join(initCount1, initCount2));
        }
      }
    }

    if (m == null) return BOTTOM;

    return new DataFlowItem(m);
  }
Esempio n. 2
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 /**
  * Check that each static final field is initialized exactly once.
  *
  * @param cb The ClassBody of the class declaring the fields to check.
  * @throws SemanticException
  */
 protected void checkStaticFinalFieldsInit(ClassBody cb) throws SemanticException {
   // check that all static fields have been initialized exactly once.
   for (Iterator iter = currCBI.currClassFinalFieldInitCounts.entrySet().iterator();
       iter.hasNext(); ) {
     Map.Entry e = (Map.Entry) iter.next();
     if (e.getKey() instanceof FieldInstance) {
       FieldInstance fi = (FieldInstance) e.getKey();
       if (fi.flags().isStatic() && fi.flags().isFinal()) {
         MinMaxInitCount initCount = (MinMaxInitCount) e.getValue();
         if (InitCount.ZERO.equals(initCount.getMin())) {
           throw new SemanticException(
               "field \"" + fi.name() + "\" might not have been initialized", cb.position());
         }
       }
     }
   }
 }
Esempio n. 3
0
 /** Perform necessary actions upon seeing the Initializer <code>initializer</code>. */
 protected void finishInitializer(
     FlowGraph graph, Initializer initializer, DataFlowItem dfIn, DataFlowItem dfOut) {
   // We are finishing the checking of an intializer.
   // We need to copy back the init counts of any fields back into
   // currClassFinalFieldInitCounts, so that the counts are
   // correct for the next initializer or constructor.
   Iterator iter = dfOut.initStatus.entrySet().iterator();
   while (iter.hasNext()) {
     Map.Entry e = (Map.Entry) iter.next();
     if (e.getKey() instanceof FieldInstance) {
       FieldInstance fi = (FieldInstance) e.getKey();
       if (fi.flags().isFinal()) {
         // we don't need to join the init counts, as all
         // dataflows will go through all of the
         // initializers
         currCBI.currClassFinalFieldInitCounts.put(fi, e.getValue());
       }
     }
   }
 }