java，tcp的socket，udp的数据报_java使用socket模拟udp-CSDN博客

本文链接：https://blog.csdn.net/bits00/article/details/8003362

tcp，socket通信

由服务器、客户端组成，需要建立连接，
server示例：

package com.server;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;

public class T_server
{
    public static void main(String[] args) throws Exception
    {
        ServerSocket ss = new ServerSocket(5466);
        while(true){
            Socket s = ss.accept();
            InputStream isA = s.getInputStream();
            BufferedReader br = new BufferedReader(new InputStreamReader(isA));
            String str = null;
            System.out.println("end:--------------------\n");
            while((str = br.readLine()) != null){
                System.out.println(str);
            }
            System.out.println("start:------------------\n");
            s.close();
        }
    }
}

client示例：

package com.client;

import java.io.BufferedWriter;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.Socket;

public class T_client
{
    public static void main(String[] args) throws Exception
    {
        Socket s = new Socket("127.0.0.1", 5466);
        OutputStream osA = s.getOutputStream();
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(osA));
        bw.write("aaaaaaaaaaaaaaa\n");
        bw.flush();
        bw.write("bbbbbbbbbbbbbbb\n");
        bw.flush();
        s.close();
    }
}

无连接的udp，数据报通信

数据报是网络上传输的独立数据包，数据报是否能到达目录，到达的时间、顺序、内容都没有保障。
server示例：

package com.server;

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

public class T_server2
{
    public static void main(String[] args) throws Exception
    {
        DatagramSocket ds = new DatagramSocket(1234);
        byte[] buf = new byte[13];
        DatagramPacket dp = new DatagramPacket(buf, 13);
        while(true){
            ds.receive(dp);
            InetAddress addr = dp.getAddress();
            int port = dp.getPort();
            byte[] data = dp.getData();
            
            System.out.println("start:-----------");
            System.out.println(addr.getHostAddress());
            System.out.println(port);
            System.out.println(new String(data));
            System.out.println("end:-----------\n");
        }
    }
}

client示例：

package com.client;

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

public class T_client2
{
    
    public static void main(String[] args) throws Exception
    {
        DatagramSocket ds = new DatagramSocket();
        
        byte[] buf = "ccccccccccccc".getBytes();
        int length = buf.length;//13
        InetAddress addr = InetAddress.getLocalHost();
        DatagramPacket dp = new DatagramPacket(buf, length, addr, 1234);
        ds.send(dp);
        ds.close();
    }
}