UDP in Java (Client)

 

import java.io.IOException;

import java.net.DatagramPacket;

import java.net.DatagramSocket;

import java.net.InetAddress;

import java.net.SocketException;

import java.net.UnknownHostException;

import org.springframework.stereotype.Service;

@Service

public class DatagramClient extends Thread {

public String userId = "";

String receivedData = "";

int mailCount = 0;

int noteCount = 0;

public DatagramClient() {

super();

}

public static void main(String[] args) {

DatagramClient client = new DatagramClient();

client.start();

}

@Override

public void run() {

try {

String sendData = "";

// DateFormat dateFormat = new SimpleDateFormat("yyyyMMddHHmmss");

// java.util.Date date = new java.util.Date();

// String time = dateFormat.format(date);

/* *

* (UDP 기반)용 프로토콜  포맷

  */

sendData = "프로토콜 작성한다";

// 전송할  DatagramPacket 생성

DatagramPacket packet = new DatagramPacket(sendData.getBytes(), sendData.getBytes().length,

InetAddress.getByName("서버아이피"), 7777); //포트 7777

// DatagramSocket 생성

DatagramSocket socket = new DatagramSocket(7777);

socket.setSoTimeout(5000);

// DatagramPacket 전송

socket.send(packet);

System.out.println("[Mail Send packet]" + packet);

// 데이터를 받을 버퍼

byte[] inbuf = new byte[100];

// 데이터를 받을 Packet  

packet = new DatagramPacket(inbuf, inbuf.length);

//데이터가 수신될 때까지 대기됨

socket.receive(packet);

// 수신된 데이터 출력

System.out.println("received length : " + packet.getLength() + ", received data : "

+ new String(packet.getData(), 0, packet.getLength()));

setMailCount(parseCountString(new String(packet.getData(), 0, packet.getLength()), 0));

setNoteCount(parseCountString(new String(packet.getData(), 0, packet.getLength()), 1));

} catch (UnknownHostException e) {

e.printStackTrace();

} catch (SocketException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

/**

* @param parseCountString : packet 받은 데이터

*/

private void setMailCount(String parseCountString) {

mailCount = Integer.parseInt(parseCountString);

}

/**

* @param parseCountString : packet 받은 데이터

*/

private void setNoteCount(String parseCountString) {

noteCount = Integer.parseInt(parseCountString);

}

/**

* @param recieved : Received data

* @param indext : 0 = 서비스1, 1 = 서비스2

* @return

*/

private String parseCountString(String recieved, int index) {

String[] array = recieved.split("|");

return array[index];

}

/**

* @return 서비스1서버에 보낼  Message Length : parameter길이

* ex) parameter(userId) 길이가 10인 경우, 0000000010

**/

String getIdString(String userId) {

String result = "";

for (int i = 0; i < 10 - (userId.length() + "").length(); i++) {

result += "0";

}

return result + userId.length();

}

public int getMailCount() {

return mailCount;

}

public int getNoteCount() {

return noteCount;

}

}