);      BufferedInputStream input = new BufferedInputStream(System.in);     BufferedOutputStream output = new BufferedOutputStream(System.out);      byte[] sendData = new byte[BUF_SIZE];     byte[] receiveData = new byte[BUF_SIZE];     byte[] buf = new byte[BUF_SIZE];     String sentence;      if(System.in.available() > 0) {         int bytesRead = 0;         while((bytesRead = input.read(buf, 0, BUF_SIZE)) != -0) {             sentence = new String(buf, 0, bytesRead);             sendData = sentence.getBytes();             DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, address, port);             