本地实现：
服务器文件（java实现）：

package socket;

import java.io.*;
import java.net.*;


public class Server {

    public static void main(String[] args) throws Exception {
        // TODO 自动生成的方法存根

        String readline = null;
        String inTemp = null;
        //String outTemp = null;
        String turnLine = "\n";
        final String client = "Client:";
        final String server = "Server:";

        int port = 60000;

        //首先直接创建serversocket
        ServerSocket serverSocket = new ServerSocket(port);//调用服务器的accept（）进行阻塞（程序会在这等待），当有申请连接时会打开阻塞并返回一个socket
        Socket socket = serverSocket.accept();

        //创建三个流，系统输入流BufferedReader systemIn，socket输入流BufferedReader socketIn，socket输出流PrintWriter socketOut;
        BufferedReader systemIn = new BufferedReader(new InputStreamReader(System.in));
        BufferedReader socketIn = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        PrintWriter socketOut = new PrintWriter(socket.getOutputStream());

        while(readline != "bye"){

            inTemp = socketIn.readLine();
            System.out.println(client + turnLine + inTemp);
            System.out.println(server);

            readline = systemIn.readLine();

            //socketOut.print(readline);//python客户端通信用这个
            socketOut.println(readline);//java客户端通信用这个
            socketOut.flush();    //赶快刷新使Client收到，也可以换成socketOut.println(readline, ture)

            //outTemp = readline;

            //System.out.println(server);

        }

        systemIn.close();
        socketIn.close();
        socketOut.close();
        socket.close();
        serverSocket.close();

    }

}

客户端文件：

package socket;

import java.io.*;
import java.net.*;

public class Client {

    public static void main(String[] args) throws Exception {
        // TODO 自动生成的方法存根

        String readline = null;
        String inTemp = null;
        //String outTemp = null;
        String turnLine = "\n";
        final String client = "Client:";
        final String server = "Server:";

        int port = 60000;
        byte ipAddressTemp[] = {127, 0, 0, 1};
        InetAddress ipAddress = InetAddress.getByAddress(ipAddressTemp);

        //首先直接创建socket,端口号1~1023为系统保存，一般设在1023之外
        Socket socket = new Socket(ipAddress, port);

        //创建三个流，系统输入流BufferedReader systemIn，socket输入流BufferedReader socketIn，socket输出流PrintWriter socketOut;
        BufferedReader systemIn = new BufferedReader(new InputStreamReader(System.in));
        BufferedReader socketIn = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        PrintWriter socketOut = new PrintWriter(socket.getOutputStream());

        while (readline != "bye") {

            System.out.println(client);
            readline = systemIn.readLine();
            //System.out.println(readline);

            socketOut.println(readline);
            socketOut.flush();    //赶快刷新使Server收到，也可以换成socketOut.println(readline, ture)

            //outTemp = readline;
            inTemp = socketIn.readLine();

            //System.out.println(client + outTemp);
            System.out.println(server + turnLine + inTemp);

        }

        systemIn.close();
        socketIn.close();
        socketOut.close();
        socket.close();

    }
}

非本地：
服务器文件（java实现）

package socket;

import java.io.*;
import java.net.*;


public class Server {

    public static void main(String[] args) throws Exception {
        // TODO 自动生成的方法存根

        String readline = null;
        String inTemp = null;
        //String outTemp = null;
        String turnLine = "\n";
        final String client = "Client:";
        final String server = "Server:";

        int port = 60000;

        //首先直接创建serversocket
        ServerSocket serverSocket = new ServerSocket(port);//调用服务器的accept（）进行阻塞（程序会在这等待），当有申请连接时会打开阻塞并返回一个socket
        Socket socket = serverSocket.accept();

        //创建三个流，系统输入流BufferedReader systemIn，socket输入流BufferedReader socketIn，socket输出流PrintWriter socketOut;
        BufferedReader systemIn = new BufferedReader(new InputStreamReader(System.in));
        BufferedReader socketIn = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        PrintWriter socketOut = new PrintWriter(socket.getOutputStream());

        while(readline != "bye"){

            inTemp = socketIn.readLine();
            System.out.println(client + turnLine + inTemp);
            System.out.println(server);

            readline = systemIn.readLine();

            socketOut.print(readline);//python客户端通信用这个
            //socketOut.println(readline);//java客户端通信用这个
            socketOut.flush();    //赶快刷新使Client收到，也可以换成socketOut.println(readline, ture)

            //outTemp = readline;

            //System.out.println(server);

        }

        systemIn.close();
        socketIn.close();
        socketOut.close();
        socket.close();
        serverSocket.close();

    }

}

客户机（python实现）

import socket
client = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
client.connect(('192.168.43.244',60000))//这里为服务器的ip地址和端口，记住端口要可用！！！
while True:
    re_data = input() +'\n'
    client.send(re_data.encode("ASCII"))
    data = client.recv(1024)
    print(data.decode("ASCII"))

最后实现时要先在客户机输入！
实现的是单线程。