private Nullness calcInherentNullability() {
    PsiModifierListOwner var = getPsiVariable();
    Nullness nullability = DfaPsiUtil.getElementNullability(getVariableType(), var);
    if (nullability != Nullness.UNKNOWN) {
      return nullability;
    }

    Nullness defaultNullability =
        myFactory.isUnknownMembersAreNullable() && MEMBER_OR_METHOD_PARAMETER.accepts(var)
            ? Nullness.NULLABLE
            : Nullness.UNKNOWN;

    if (var instanceof PsiParameter && var.getParent() instanceof PsiForeachStatement) {
      PsiExpression iteratedValue = ((PsiForeachStatement) var.getParent()).getIteratedValue();
      if (iteratedValue != null) {
        PsiType itemType = JavaGenericsUtil.getCollectionItemType(iteratedValue);
        if (itemType != null) {
          return DfaPsiUtil.getElementNullability(itemType, var);
        }
      }
    }

    if (var instanceof PsiField
        && DfaPsiUtil.isFinalField((PsiVariable) var)
        && myFactory.isHonorFieldInitializers()) {
      List<PsiExpression> initializers = DfaPsiUtil.findAllConstructorInitializers((PsiField) var);
      if (initializers.isEmpty()) {
        return defaultNullability;
      }

      boolean hasUnknowns = false;
      for (PsiExpression expression : initializers) {
        Nullness nullness = getFieldInitializerNullness(expression);
        if (nullness == Nullness.NULLABLE) {
          return Nullness.NULLABLE;
        }
        if (nullness == Nullness.UNKNOWN) {
          hasUnknowns = true;
        }
      }

      if (hasUnknowns) {
        if (DfaPsiUtil.isInitializedNotNull((PsiField) var)) {
          return Nullness.NOT_NULL;
        }
        return defaultNullability;
      }

      return Nullness.NOT_NULL;
    }

    return defaultNullability;
  }
 public boolean isFlushableByCalls() {
   if (myVariable instanceof PsiLocalVariable || myVariable instanceof PsiParameter) return false;
   if (myVariable instanceof PsiVariable && myVariable.hasModifierProperty(PsiModifier.FINAL)) {
     return myQualifier != null && myQualifier.isFlushableByCalls();
   }
   return true;
 }
 private DfaVariableValue(
     @NotNull PsiModifierListOwner variable,
     @Nullable PsiType varType,
     boolean isNegated,
     DfaValueFactory factory,
     @Nullable DfaVariableValue qualifier) {
   super(factory);
   myVariable = variable;
   myIsNegated = isNegated;
   myQualifier = qualifier;
   myVarType = varType;
   DfaValue typeValue = myFactory.createTypeValue(varType, Nullness.UNKNOWN);
   myTypeValue = typeValue instanceof DfaTypeValue ? (DfaTypeValue) typeValue : null;
   if (varType != null && !varType.isValid()) {
     PsiUtil.ensureValidType(
         varType, "Variable: " + variable + " of class " + variable.getClass());
   }
 }