@Override
    public void set(final F obj) {
      checkConcurrent();
      if (!canset) {
        throw new IllegalStateException("Can not set an element "
                                        + "unless either next() or previous() has been called since the "
                                        + "last remove() or set()");
      }

      filterlist.set(cursor, obj);
      expectedmod = getModCount();
    }
@Override
    public void set(final F obj)