private void writeOP(SelectionKey key) {
        SocketChannel socketChannel = (SocketChannel) key.channel();
        ByteBuffer dummyResponse = null;
        try {
            dummyResponse = ByteBuffer.wrap("ok".getBytes("UTF-8"));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

        try {
            socketChannel.write(dummyResponse);
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (dummyResponse.remaining() > 0) {
            System.err.print("Filled UP");
        }

        key.interestOps(SelectionKey.OP_READ);
    }