@Override
  public boolean isSameFile(FileObject a, FileObject b) {
    final FileObject _a = unwrapFileObject(a);
    final FileObject _b = unwrapFileObject(b);
    if (_a instanceof JpsFileObject || _b instanceof JpsFileObject) {
      return _a.equals(_b);
    }
    return super.isSameFile(_a, _b);
  }
@Override
  public boolean isSameFile(FileObject a, FileObject b)