Udpの使用と応用

目次

1.入門

1.1. 送信側

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;

/**
 *  udp （ ）
 * @date 2018 2 5 
 */
public class Sender {

    /**
     * udp 
     *  ：DatagramSocket，DatagramPacket
     * @param args    
     * @throws SocketException
     */
    public static void main(String[] args) throws Exception {
        //1. udp 
        DatagramSocket datagramSocket = new DatagramSocket();
        //2. 
        String data = " socket ";
        byte datas[] = data.getBytes();
        DatagramPacket datagramPacket = new DatagramPacket(datas, datas.length, InetAddress.getLocalHost(), 9090);
        //3. udp 
        datagramSocket.send(datagramPacket);
        //4. （ ）
        datagramSocket.close();
    }
}

1.2. じゅしんたんし

import java.net.DatagramPacket;
import java.net.DatagramSocket;

/**
 *  udp （ ）
 * @date 2018 2 5 
 */
public class Receive {

    public static void main(String[] args) throws Exception {
        //1. udp ， 9090 
        DatagramSocket socket = new DatagramSocket(9090);
        //2. 
        byte buf[] = new byte[1024];
        DatagramPacket packet = new DatagramPacket(buf,buf.length);
        //3. udp 
        socket.receive(packet);//receive ， 
        System.out.println(" : "+new String(buf,0,packet.getLength()));//getLength() 
        //4. 
        socket.close();
    }
}

2.通信ソフトへのメッセージ送信

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

/**
 *  FeiQ 
 * @date 2018 2 5 
 */
public class SendFeiQ {

    public static void main(String[] args) throws Exception {
        DatagramSocket socket = new DatagramSocket();
        // 
        byte buf[] = getFeiQData("Hi FeiQ!").getBytes();
        DatagramPacket packet = new DatagramPacket(buf, buf.length, InetAddress.getLocalHost(), 2425);
        socket.send(packet);
        socket.close();
        }
        /**
         *  ， 
         * feiQ ：
         * version:time:sender:ip:flag:content
         *   ： ： ：IP ： （32）： ；
         * @param data
         * @return    
         */
        public static String getFeiQData(String centent){
        StringBuilder data = new StringBuilder();
        data.append("1.0:");
        data.append(System.currentTimeMillis()+":");
        data.append(" :");
        data.append("192.168.0.107:");
        data.append("32:");
        data.append(centent);
        return data.toString();
    }
}

3.マルチチャットの実現

3.1. 送信側

/**
 * udp （ ）
 * @date 2018 2 5 
 */
public class CharSender extends Thread{

    @Override
    public void run() {
        DatagramSocket socket = null;
        BufferedReader reader = null;
        try {
            socket = new DatagramSocket();
            // 
            reader = new BufferedReader(new InputStreamReader(System.in));
            String line = null;
            DatagramPacket packet = null;
            while ((line = reader.readLine()) != null) {// ( 3 .255)
                packet = new DatagramPacket(line.getBytes(), line.getBytes().length,InetAddress.getByName("192.168.0.255"),9090);
                socket.send(packet);
            }
        } catch (SocketException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                reader.close();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                socket.close();
            }
        }
    }
}

3.2. じゅしんたんし

import java.net.DatagramPacket;
import java.net.DatagramSocket;

/**
 * udp （ ）
 * @date 2018 2 5 
 */
public class CharRecevice extends Thread{
    @Override
    public void run() {
        DatagramSocket socket = null;
        try {
            socket = new DatagramSocket(9090);
            byte buf[] = new byte[1024];
            DatagramPacket packet = new DatagramPacket(buf,buf.length);
            while (true) {
                socket.receive(packet);
                System.out.println(packet.getAddress().getHostAddress()+" ："+new String(buf,0,packet.getLength()));
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            socket.close();
        }
    }
}

3.3. 呼び出し先

public class ChatMain {

    public static void main(String[] args) {
        // ， 
        ChatRecevice recevice = new ChatRecevice();
        ChatSender sender = new ChatSender();
        recevice.start();
        sender.start();
    }
}