完成服务器端和客户端的双向通讯。
NET/SocketTest1.java

package cn.antraces.NET;

import javax.swing.;
import java.awt.;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.text.SimpleDateFormat;
import java.util.Date;


public class SocketTest1 implements Runnable{


    public JFrame jf;
    public JPanel jp;
    public JButton jButton_Send, jButton_Stop;
    public JTextArea jTextArea;
    public JTextField jTextField;
    public JScrollPane jScrollPane;
    public Socket socket1, socket2;
    public ServerSocket serverSocket;
    public BufferedReader bufferedReader;
    public int m;
    public boolean on;

    @Override
    public void run() {
        try {
            if (m == 1) {
                server();
                bufferedReader = new BufferedReader(new InputStreamReader(socket1.getInputStream()));
                on = true;
                while (on){
                    client();
                }
            } else if (m == 2) {
                on = true;
                socket2 = new Socket("127.0.0.1",23333);
                bufferedReader = new BufferedReader(new InputStreamReader(socket2.getInputStream()));
                while (on){
                    client();
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public SocketTest1(int m){
        this.m = m;
        String title = "";
        if (m == 1) {
            title = "服务端";
        } else if (m == 2) {
            title = "客户端";
        }

        JFrame jf = new JFrame(title);
        jf.setSize(400, 400);
        jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        jf.setLocationRelativeTo(null);
        jf.setResizable(false);

        JPanel jp = new JPanel(new FlowLayout());

        jTextField = new JTextField(16);
        jTextField.setFont(new Font(null, Font.PLAIN, 18));

        jButton_Send = new JButton("发送");
        jButton_Stop = new JButton("断开");

        jButton_Send.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent actionEvent) {

                PrintWriter printWriter = null;
                try {
                    if (m == 1)
                        printWriter = new PrintWriter(socket1.getOutputStream(), true);
                    else if (m == 2)
                        printWriter = new PrintWriter(socket2.getOutputStream(), true);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                printWriter.println(jTextField.getText());
                String str = "";
                Date nowDate = new Date();
                SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss:SSS");

                if ((str = jTextArea.getText()) != null) {
                    jTextArea.append("\r\n" + sdf.format(nowDate.getTime()) + "\r\n  " + jTextField.getText());
                }

                jTextField.setText("");
            }
        });

        jButton_Stop.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent actionEvent) {
                on = false;
                jTextField.setEditable(false);
                jTextArea.append("\r\n" + "-=-=-=-=-=-=-=-=-=-连接已断开-=-=-=-=-=-=-=-=-=-");
                try {
                    if (socket1 != null)
                        socket1.close();
                    if (socket2 != null)
                        socket2.close();
                    if (serverSocket != null)
                        serverSocket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });

        jTextArea = new JTextArea(19, 32);
        jTextArea.setText("-=-=-=-=-=-=-=-=-=-连接已启动-=-=-=-=-=-=-=-=-=-");
        jTextArea.setLineWrap(false);
        jTextArea.setEnabled(false);
        jScrollPane = new JScrollPane(jTextArea);

        jp.add(jScrollPane);
        jp.add(jTextField);
        jp.add(jButton_Send);
        jp.add(jButton_Stop);

        jf.setContentPane(jp);
        jf.setVisible(true);

        Thread th = new Thread(this);
        th.start();
    }

    public void server() throws IOException {
        serverSocket = new ServerSocket(23333);
        socket1 = serverSocket.accept();
    }

    public void client() throws IOException {
        String str = bufferedReader.readLine();
        if (str != null) {
            Date nowDate = new Date();
            SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss:SSS");
            if (m == 1)
                jTextArea.append("\r\nClient - " + sdf.format(nowDate.getTime()) + "\r\n  " + str);
            if (m == 2)
                jTextArea.append("\r\nServer - " + sdf.format(nowDate.getTime()) + "\r\n  " + str);
        }
    }

    public static void main (String[] args){
        new SocketTest1(1);
        new SocketTest1(2);
    }



`}
`

在上次代码的基础上改了一点点东西...