窗体代码可以自己随便写写，不用非得和视频里的一样

import javax.swing.*;

import java.awt.event.*;

import java.io.IOException;

import java.net.UnknownHostException;

import java.text.SimpleDateFormat;

import java.util.Date;

import javax.swing.SwingConstants;

import javax.swing.border.EmptyBorder;

/**

 * 客户端窗体

 */

public class ClientFrame extends JFrame {

private JPanel contentPane;

private JLabel lblUserName;// 显示用户名

private JTextField tfMessage; // 信息发送文本框

private JButton btnSend;// 发送按钮

private JTextArea textArea;// 信息接收文本域

private String userName;// 用户名称

private ChatRoomClient client;// 客户端连接对象

/**

* 客户端窗体的构造方法

* 

* @param ip

*            服务器IP地址

* @param userName

*            用户名

*/

public ClientFrame(String ip, String userName) {

this.userName = userName;

try {

client = new ChatRoomClient(ip, 4569);// 创建客户端对象

} catch (UnknownHostException e1) {

e1.printStackTrace();

} catch (IOException e1) {

e1.printStackTrace();

}

ReadMessageThread messageThread = new ReadMessageThread();// 创建读取客户端消息的线程类对象

messageThread.start();// 启动读取客户端消息的线程类对象

init();// 添加窗体初始化内容

addListener();// 添加窗体监听内容

}

private void init() {

setTitle("客户端");

setResizable(false);

setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);

setBounds(100, 100, 450, 300);

contentPane = new JPanel();

contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));

contentPane.setLayout(null);

setContentPane(contentPane);

JScrollPane scrollPane = new JScrollPane();

scrollPane.setBounds(5, 5, 434, 229);

contentPane.add(scrollPane);

textArea = new JTextArea();

scrollPane.setViewportView(textArea);

textArea.setEditable(false);// 文本域不可编辑

JPanel panel = new JPanel();

panel.setBounds(5, 235, 434, 32);

contentPane.add(panel);

panel.setLayout(null);

lblUserName = new JLabel(userName);

lblUserName.setHorizontalAlignment(SwingConstants.TRAILING);

lblUserName.setBounds(2, 4, 55, 22);

panel.add(lblUserName);

tfMessage = new JTextField();

tfMessage.setBounds(62, 5, 274, 22);

tfMessage.setColumns(10);

panel.add(tfMessage);

btnSend = new JButton("发送");

btnSend.setBounds(336, 4, 93, 23);

panel.add(btnSend);

tfMessage.validate();

}

private void addListener() {

btnSend.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

Date date = new Date();// 创建时间类

SimpleDateFormat df = new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");// 设定日期格式

client.sendMessage(userName + "  " + df.format(date) + "：\n   " + tfMessage.getText());// 向服务器发送文本内容

tfMessage.setText("");// 输入框为空

}

});

this.addWindowListener(new WindowAdapter() {// 开启窗口监听

public void windowClosing(WindowEvent atg0) {// 窗口关闭时

int op = JOptionPane.showConfirmDialog(ClientFrame.this, "确定要退出聊天室吗？", "确定", JOptionPane.YES_NO_OPTION);// 弹出提示框

if (op == JOptionPane.YES_OPTION) {// 如果选择是

client.sendMessage("%EXIT%:" + userName);// 发送消息

try {

Thread.sleep(200);

} catch (InterruptedException e) {

e.printStackTrace();

}

client.close();// 关闭客户端连接

System.exit(0);// 关闭程序

}

}

});

}

/**

* 读取客户端消息的线程类

*/

private class ReadMessageThread extends Thread {

public void run() {// 线程主方法

while (true) {// 无限循环

String str = client.reciveMessage();// 客户端收到服务器发来的文本内容

textArea.append(str + "\n");// 向文本框添加文本内容

}

}

}

}

import javax.swing.*;

import javax.swing.border.EmptyBorder;

import java.awt.Font;

import java.awt.event.*;

/**

 * 连接服务器窗体

 */

@SuppressWarnings("serial") // 通过注解抑制编译器警告

public class LinkServerFrame extends JFrame {

private JPanel contentPane;

private JLabel lblIP;

private JLabel lblUserName;

private JTextField tfIP;

private JTextField tfUserName;

private JButton btnLink;

/**

* 连接服务器窗体的构造方法

*/

public LinkServerFrame() {

setTitle("连接服务器");

setResizable(false);

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

setBounds(100, 100, 390, 150);

contentPane = new JPanel();

contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));

contentPane.setLayout(null);

setContentPane(contentPane);

lblIP = new JLabel("服务器IP地址：");

lblIP.setFont(new Font("微软雅黑", Font.PLAIN, 14));

lblIP.setBounds(20, 15, 100, 15);

contentPane.add(lblIP);

tfIP = new JTextField("127.0.0.1");

tfIP.setBounds(121, 13, 242, 21);

contentPane.add(tfIP);

tfIP.setColumns(10);

lblUserName = new JLabel("用户名：");

lblUserName.setFont(new Font("微软雅黑", Font.PLAIN, 14));

lblUserName.setBounds(60, 40, 60, 15);

contentPane.add(lblUserName);

tfUserName = new JTextField();

tfUserName.setBounds(121, 42, 242, 21);

contentPane.add(tfUserName);

tfUserName.setColumns(10);

btnLink = new JButton("连接服务器");

btnLink.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

do_btnLink_actionPerformed(e);

}

});

btnLink.setFont(new Font("微软雅黑", Font.PLAIN, 14));

btnLink.setBounds(140, 80, 120, 23);

contentPane.add(btnLink);

}

public static void main(String[] args) {

LinkServerFrame linkServerFrame = new LinkServerFrame();// 创建连接服务器窗体对象

linkServerFrame.setVisible(true);// 显示连接服务器窗体

}

protected void do_btnLink_actionPerformed(ActionEvent e) {

if (!tfIP.getText().equals("") && !tfUserName.getText().equals("")) {// 文本框中的内容不为空时

dispose();// 销毁当前窗体

ClientFrame clientFrame = new ClientFrame(tfIP.getText().trim(), tfUserName.getText().trim());// 创建客户端窗体对象并传参

clientFrame.setVisible(true);// 显示客户端窗体

} else {

JOptionPane.showMessageDialog(null, "文本框里的内容不能为空！", "警告", JOptionPane.WARNING_MESSAGE);

}

}

}