UDP client,UDP server, TCP server, TCP client

UDP server

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketException;

/**
 * udpserver 
 * 监听端口 10001
 * @author GXF
 *
 */
public class UdpSocketServer {
    private DatagramSocket serverSocket;
    
    public UdpSocketServer(int port){
        init(port);
    }
    
    public void init(int port){
        
        InetSocketAddress serverSocketAddress = new InetSocketAddress( port);
        try {
            serverSocket = new DatagramSocket(serverSocketAddress);
        } catch (SocketException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    //监听端口
    public void startListen(){
        byte buff[] = new byte[1024];
        DatagramPacket receivePacket = new DatagramPacket(buff, buff.length);
        while(true){
            try {
                serverSocket.receive(receivePacket);
                String message = new String(buff, 0, receivePacket.getLength());
                System.out.println("message from client = " + message);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
    
    public static void main(String args[]){
        UdpSocketServer udpSocketServer = new UdpSocketServer(10001);
        udpSocketServer.startListen();
    }
}

UDP client

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.SocketException;
import java.net.UnknownHostException;

/**
 * Udp客户端  DatagramSocket
 * @author GXF
 *
 */
public class UdpSocketClient {
    //客户端套接字
    private DatagramSocket clientSocket;
    
    //构造方法
    public UdpSocketClient(String ip, int port){
        init(ip, port);
    }
    
    /**
     * 初始化套接字
     * @param ip
     * @param port
     */
    public void init(String ip, int port){
//        try {
//            InetAddress serverAddress = InetAddress.getByName(ip);
//            InetSocketAddress serverSocketAddress = new InetSocketAddress(serverAddress, port);
            try {
                clientSocket = new DatagramSocket();
            } catch (SocketException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
//        } catch (UnknownHostException | SocketException e) {
//            e.printStackTrace();
//        }
    }
    
    /**
     * 使用UDP向服务器发送消息
     * @param ip
     * @param message
     */
    public void sendMessage(String message){
        byte buff[] = message.getBytes();
        DatagramPacket packetToSend;
        try {
            packetToSend = new DatagramPacket(buff, buff.length, InetAddress.getByName("127.0.0.1"), 10002);
            clientSocket.send(packetToSend);                                                    //发送数据包
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }                                                    
    }
    
    public static void main(String[] args) {
        String serverIp = "127.0.0.1";
        int port = 10001;
        UdpSocketClient clientSocket = new UdpSocketClient(serverIp, port);
        String message = "hahahahah";
        clientSocket.sendMessage(message);

    }

}

TCP server

import java.io.IOException;
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class TcpServer {
    private ServerSocket serverSocket;
    
    TcpServer(int port){
        try {
            serverSocket = new ServerSocket(port);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    //开始监听端口
    public void start(){
        while(true){
            try {
                Socket clientSocket = serverSocket.accept();
                InputStream is = clientSocket.getInputStream();
                byte buff[] = new byte[1024];
                int length = -1;
                StringBuilder sb = new StringBuilder();
//                while((length = is.read(buff)) > 0){
                length = is.read(buff);
                    sb.append(new String(buff, 0, length));
//                }//while
                System.out.println("message received: " + sb.toString());
                clientSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            
        }
    }
    
    public static void main(String args[]){
        int port = 10002;
        TcpServer tcpServer = new TcpServer(port);
        tcpServer.start();
    }
}

Tcp client

import java.io.IOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.util.Scanner;

public class TcpClient {
    private Socket socket;
    private int port;
    
    private TcpClient(int port){
//        try {
            this.port = port;
//        } catch (IOException e) {
//            e.printStackTrace();
//        }
    }
    
    /**
     * 发送消息
     * @param message
     */
    public void sendMessage(String message){
        try {
            Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), port);
            OutputStream os = socket.getOutputStream();
            byte buff[] = message.getBytes();
            os.write(buff);
            os.flush();
            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        
    }
    
    public void inputMessage(){
        Scanner scanner = new Scanner(System.in);
        while(true){
            String message = scanner.nextLine();
            sendMessage(message);
        }
    }
    
    public static void main(String[] args) {
        int port = 10001;
        TcpClient client = new TcpClient(port);
        client.inputMessage();
    }

}