@Override
    public void indexStub(@NotNull PsiClassStub stub, @NotNull IndexSink sink) {
      StubElement parent = stub.getParentStub();
      if (parent instanceof PsiJavaFileStub) {
        sink.occurrence(JavaStubIndexKeys.IMPLICIT_CLASSES, JavaImplicitClassUtil.getJvmName(((PsiJavaFileStub)parent).getPsi().getName()));
      }
    }
@Override
    public void indexStub(@NotNull PsiClassStub stub, @NotNull IndexSink sink)