private 声明的对象能被.直接引用问题

Question

private class ViewHolder extends RecyclerView.ViewHolder {

    private TextView tv_name;

    public ViewHolder(View itemView) {
        super(itemView);
        tv_name = itemView.findViewById(R.id.tv_name);
    }
}

      @Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
    if (holder instanceof ViewHolder) {
       Bean bean = mlist.get(position);
        ((ViewHolder) holder).tv_name.setText(bean.getTdi_name());
    }
}

    为什么我在ViewHolder类private声明的控件 能直接被.调用，有点无法理解，还望指教。