@Override
    public void add(final Content obj) {
      checkConcurrent();
      // always add before what would normally be returned by next();
      final int next = forward ? cursor + 1 : cursor;

      ContentList.this.add(next, obj);

      expectedmod = getModCount();

      canremove = canset = false;

      // a call to next() should be unaffected, so, whatever was going to
      // be next will still be next, remember, what was going to be next
      // has been shifted 'right' by our insert.
      // we ensure this by setting the cursor to next(), and making it
      // forward
      cursor = next;
      forward = true;
    }
@Override
    public void add(final Content obj)