用 Java 写了一个类QQ界面聊天小项目，可在线聊天！

Java就该这么学 2023-09-18

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大家好，我是Java就该这么学。
1.功能实现

1.修改功能（密码、昵称、个性签名）
2.添加好友、删除好友
3.单聊功能
4.判断好友是否在线

2.模块划分

3.使用的知识

netty
swing
集合等同步阻塞队列synchronousQueue
数据库MySQL中的CRUD
C3p0连接池
JSON字符串

4.部分代码实现

1.nettyController.java

接收到来自客户端的消息，与dao层进行交互
dao层与之数据库进行交互

修改密码
添加好友

从添加好友逻辑实现上我走了很多的弯路频繁的访问数据库，这是一件很不好的事情。另外，搜索公众号技术社区后台回复“算法”，获取一份惊喜礼包。

package chat.Project.controller;

import chat.Project.bean.information;
import chat.Project.constant.EnMsgType;
import chat.Project.dao.*;
import chat.utils.CacheUtil;
import chat.utils.JsonUtils;
import com.fasterxml.jackson.databind.node.ObjectNode;
import io.netty.channel.Channel;

import java.util.ArrayList;
import java.util.Iterator;

public class NettyController {

    private static UserDao userDao = new UserDaoImpl();
    private static informationDao informationDao = new informationDaoImpl();
    private static friendDao friendDao = new friendDaoImpl();

    public static String processing(String message, Channel channel){

        //解析客户端发送的消息
        ObjectNode jsonNodes = JsonUtils.getObjectNode(message);
        String msgtype = jsonNodes.get("msgtype").asText();
        if (EnMsgType.EN_MSG_LOGIN.toString().equals(msgtype)){
            //登录操作
            return loginOperation(jsonNodes,channel);
        }else if (EnMsgType.EN_MSG_MODIFY_SIGNATURE.toString().equals(msgtype)){
            //修改签名
            return modifySignature(jsonNodes);
        }else if (EnMsgType.EN_MSG_MODIFY_NICKNAME.toString().equals(msgtype)){
            //修改昵称
            return modifyNickname(jsonNodes);
        }else if (EnMsgType.EN_MSG_GETINFORMATION.toString().equals(msgtype)){
            //获取登录信息
            return getInformation(jsonNodes);
        }else if (EnMsgType.EN_MSG_VERIFY_PASSWORD.toString().equals(msgtype)){
            //进行修改密码
            return verifyPasswd(jsonNodes);
        }else if (EnMsgType.EN_MSG_CHAT.toString().equals(msgtype)){
            //单聊模式
            return SingleChat(jsonNodes);
        }else if (EnMsgType.EN_MSG_GET_ID.toString().equals(msgtype)){
            //获取id
            return getId(jsonNodes);
        }else if (EnMsgType.EN_MSG_GET_FRIEND.toString().equals(msgtype)){
            //获取好友列表
            return getFriend(jsonNodes);
        }else if (EnMsgType.EN_MSG_ADD_FRIEND.toString().equals(msgtype)){
            //添加好友
            return addFriends(jsonNodes);
        }else if (EnMsgType.EN_MSG_DEL_FRIEND.toString().equals(msgtype)){
            //删除好友
            return delFriend(jsonNodes);
        }else if (EnMsgType.EN_MSG_ACTIVE_STATE.toString().equals(msgtype)){
            //判断好友的在线状态
            return friendIsActive(jsonNodes);
        }
        return "";
    }

    //判断好友在线状态
    private static String friendIsActive(ObjectNode jsonNodes) {
        int friendId = jsonNodes.get("friendId").asInt();

        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_ACTIVE_STATE.toString());

        //客户端保证用户独立存在且是好友
        Channel channel = CacheUtil.get(friendId);
        //判断用户是否在线
        if (channel == null){
            //用户不在线
            objectNode.put("code",200);
        }else {
            //用户在线
            objectNode.put("code",300);
        }
        return objectNode.toString();
    }

    //添加好友
    private static String delFriend(ObjectNode jsonNodes) {
        Integer friendId = jsonNodes.get("friendId").asInt();
        int userId = jsonNodes.get("id").asInt();
        String localName = jsonNodes.get("localName").asText();

        //封装发回客户端的JSON
        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_DEL_FRIEND.toString());
        objectNode.put("code",200);

        //验证是否存在当前好友
        information information = informationDao.getInformation(friendId);
        String friendName = information.getNickname();
        //查询自己是否有该好友
        boolean exist = friendDao.isExist(friendName,userId);
        if (exist){
            //存在当前好友进行删除操作
            friendDao.delFriend(userId,friendName);
            friendDao.delFriend(friendId,localName);
            objectNode.put("code",300);
        }
        return objectNode.toString();
    }

    //添加好友
    private static String addFriends(ObjectNode jsonNodes) {
        Integer friendId = jsonNodes.get("friendId").asInt();
        int userId = jsonNodes.get("id").asInt();
        String localName = jsonNodes.get("localName").asText();

        //验证是否有ID
        boolean exists = userDao.verifyExistFriend(friendId);
        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_ADD_FRIEND.toString());
        objectNode.put("code",200);

        if(exists){
            //表示存在此id
            objectNode.put("code",300);
            //获取好友昵称
            information information = informationDao.getInformation(friendId);
            String friendNickname = information.getNickname();
            //进行添加好友的操作   两个对应的信息都应该添加
            friendDao.addFriends(userId,localName,friendNickname);
            friendDao.addFriends(friendId,friendNickname,localName);
        }
        return objectNode.toString();
    }

    //获取好友列表
    private static String getFriend(ObjectNode jsonNodes) {

        int uid = jsonNodes.get("uid").asInt();

        //返回ArrayLis集合
        ArrayList<String> friends = friendDao.getFriends(uid);
        //封装JSON
        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_GET_FRIEND.toString());

        //写回friend集合
        Iterator<String> iterator = friends.iterator();
        int i = 0;
        while (iterator.hasNext()){
            objectNode.put("res"+i,iterator.next());
            i++;
        }
        //记录好友个数
        objectNode.put("count",i);

        return objectNode.toString();
    }

    //获取id
    private static String getId(ObjectNode jsonNodes) {
        String nickname = jsonNodes.get("nickname").asText();
        information information = informationDao.nicknameGetId(nickname);
        //联系人的id
        int uid = information.getUid();
        //封装JSON
        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_GET_ID.toString());
        objectNode.put("uid",uid);
        return objectNode.toString();
    }

    //单聊模式
    private static String SingleChat(ObjectNode jsonNodes) {

        int id = jsonNodes.get("id").asInt();

        //根据id在friend表获取登录用户名

        //封装JSON数据服务端转发数据
        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_CHAT.toString());

        //客户端保证用户独立存在且是好友
        Channel channel = CacheUtil.get(id);
        //判断用户是否在线
        if (channel == null){
            //用户不在线
            objectNode.put("code",200);
        }else{
            //用户在线
            objectNode.put("code",300);
            //消息转发
            channel.writeAndFlush(jsonNodes.toString());
        }
        return objectNode.toString();
    }

    //修改密码
    private static String verifyPasswd(ObjectNode jsonNodes) {
        int id = jsonNodes.get("id").asInt();
        String oldPasswd = jsonNodes.get("oldPasswd").asText();
        String newPasswd = jsonNodes.get("newPasswd").asText();

        boolean exits = userDao.verifyPassword(oldPasswd, id);

        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_VERIFY_PASSWORD.toString());
        objectNode.put("code",200);
        if (exits){
            //验证成功
            userDao.modifyPasswd(newPasswd,id);
            objectNode.put("code",300);
        }
        return objectNode.toString();
    }

    //获取信息
    private static String getInformation(ObjectNode jsonNodes) {
        int id = jsonNodes.get("id").asInt();

        information information = informationDao.getInformation(id);

        //封装JSON发回客户端
        ObjectNode objectNode = JsonUtils.getObjectNode();
        objectNode.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        objectNode.put("srctype",EnMsgType.EN_MSG_GETINFORMATION.toString());
        objectNode.put("Nickname",information.getNickname());
        objectNode.put("Signature",information.getSignature());

        return objectNode.toString();
    }

    //修改昵称
    private static String modifyNickname(ObjectNode jsonNodes) {
        int id = jsonNodes.get("id").asInt();
        String nickname = jsonNodes.get("nickname").asText();
        //进行存储
        informationDao.storeNickname(nickname,id);
        return "";
    }

    //修改签名
    private static String modifySignature(ObjectNode jsonNodes) {
        int id = jsonNodes.get("id").asInt();
        String signature = jsonNodes.get("signature").asText();
        //进行存储
        informationDao.storeSignature(signature,id);
        return "";
    }

    //登录操作
    private static String loginOperation(ObjectNode objectNode,Channel channel) {

        int id = objectNode.get("id").asInt();
        String passwd = objectNode.get("passwd").asText();
        //进行数据库查询
        boolean exits = userDao.getInformation(id, passwd);

        ObjectNode jsonNodes = JsonUtils.getObjectNode();
        jsonNodes.put("msgtype",EnMsgType.EN_MSG_ACK.toString());
        jsonNodes.put("srctype",EnMsgType.EN_MSG_LOGIN.toString());
        jsonNodes.put("code",300);
        //返回状态码
        if (exits){
            jsonNodes.put("code",200);

            //添加用户的在线信息
            CacheUtil.put(id,channel);
        }
        return jsonNodes.toString();
    }
}

2.ClientHandler.java

客户端接受来自服务端返回的消息
根据返回的状态码来判断是否操作成功

package chat.Project.netty;

import chat.Frame.chat.ChatFrame;
import chat.Frame.chat.linkmen;
import chat.Frame.chat.login;
import chat.Project.constant.EnMsgType;
import chat.util.JsonUtils;
import com.fasterxml.jackson.databind.node.ObjectNode;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;

import java.util.concurrent.SynchronousQueue;


public class ClientHandler extends SimpleChannelInboundHandler<String> {

    //定义一个同步阻塞队列状态码
    public static SynchronousQueue<Object> queue = new SynchronousQueue<>();

    public static String Nickname;
    public String Signature;

    @Override
    protected void channelRead0(ChannelHandlerContext channelHandlerContext, String s) throws Exception {

    }

    //客户端接收数据
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        System.out.println(msg);
        //解析服务端发送的消息
        ObjectNode jsonNodes = JsonUtils.getObjectNode((String) msg);
        String msgtype = jsonNodes.get("msgtype").asText();
        if (EnMsgType.EN_MSG_ACK.toString().equals(msgtype)) {
            String srctype = jsonNodes.get("srctype").asText();
            if (EnMsgType.EN_MSG_LOGIN.toString().equals(srctype)) {
                //登录操作
                queue.offer(jsonNodes.get("code").asInt());
            }else if(EnMsgType.EN_MSG_GETINFORMATION.toString().equals(srctype)){
                //存取信息
                 Nickname = jsonNodes.get("Nickname").asText();
                 Signature = jsonNodes.get("Signature").asText();
                linkmen.label_1.setText(Nickname);
                linkmen.field.setText(Signature);
            }else if (EnMsgType.EN_MSG_CHAT.toString().equals(srctype)){
                //发送端返回消息
                queue.offer(jsonNodes.get("code").asInt());
            }else if (EnMsgType.EN_MSG_GET_ID.toString().equals(srctype)){
                int uid = jsonNodes.get("uid").asInt();
                queue.offer(uid);
            }else if (EnMsgType.EN_MSG_GET_FRIEND.toString().equals(srctype)){
                //获取登录用户的好友
                int count = jsonNodes.get("count").asInt();
                login.friend = new String[count];
                for ( int i = 0;i<count;i++){
                    login.friend[i] = jsonNodes.get("res"+i).asText();
                    System.out.println(jsonNodes.get("res"+i));
                }
            }else if (EnMsgType.EN_MSG_ADD_FRIEND.toString().equals(srctype)){
                //添加好友
                queue.offer(jsonNodes.get("code").asInt());
            }else if (EnMsgType.EN_MSG_DEL_FRIEND.toString().equals(srctype)){
                //删除好友
                queue.offer(jsonNodes.get("code").asInt());
            }else if (EnMsgType.EN_MSG_ACTIVE_STATE.toString().equals(srctype)){
                //好友在线状态
                queue.offer(jsonNodes.get("code").asInt());
            }
        }else if (EnMsgType.EN_MSG_VERIFY_PASSWORD.toString().equals(msgtype)){
            //修改密码
            int code = 0;
            code = jsonNodes.get("code").asInt();
            queue.offer(code);
        }else if (EnMsgType.EN_MSG_CHAT.toString().equals(msgtype)){
            //接收端接受消息  封装朋友昵称
            String message = " "+ jsonNodes.get("message").asText();
            //聊天显示框读取消息
            ChatFrame.sb.append(message+"\n");
            ChatFrame.displayTextPanel.setText(ChatFrame.sb.toString());
        }
    }

}

3.linkmen.java

这是登录成功的界面

牛逼啊！接私活必备的 N 个开源项目！赶快收藏

package chat.Frame.chat;

import chat.Frame.operation.alterColumn.changeNickname;
import chat.Frame.operation.alterColumn.changePassword;
import chat.Frame.operation.alterColumn.changeSignature;
import chat.Frame.operation.friendHandle.addFriend;
import chat.Frame.operation.friendHandle.delFriend;
import chat.Frame.tipFrame;
import chat.Project.services.sendServers;
import io.netty.channel.Channel;

import javax.swing.*;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import java.awt.*;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;


/**
 * 联系人界面
 */
public class linkmen extends JFrame {
    //容器
    private JFrame frame;
    //标签
    private JLabel  label_2, label_3, label_4, label;
    //昵称
    public static JLabel label_1;
    //状态框
    private JComboBox box, box_1, box_2;
    //图片
    private ImageIcon icon_1, icon;
    //文本
    private JTextField  field_1;
    //个性签名
    public static JTextField field;
    //面板
    private JPanel panel_1, panel_3, panel;
    //滚动面板
    public JScrollPane panel_2;
    //列表
    public static JList list;
    //与服务端通信的通道
    private Channel channel;
    //用户的id
    private Integer id;
    //暂存oldPasswd
    public static JLabel label_5,label_6;
    //好友列表数组
    private String[] fd;
    //列表
    public static DefaultListModel<String> model;

    public linkmen(Integer id, Channel channel,String[] fd) {
        this.id = id;
        this.channel = channel;
        this.fd = fd;
    }

    public void init() {
        //初始化面板1并设置信息
        panel_1 = new JPanel();
        panel_1.setLayout(null);
        panel_1.setLocation(0, 0);
        panel_1.setBorder(BorderFactory.createTitledBorder("资料卡"));
        panel_1.setSize(new Dimension(295, 148));
        panel_1.setOpaque(false);


        //初始化面板3并设置信息
        panel_3 = new JPanel();
        panel_3.setLayout(null);
        panel_3.setBorder(BorderFactory.createTitledBorder("系统设置"));
        panel_3.setLocation(0, 617);
        panel_3.setSize(new Dimension(295, 55));
        panel_3.setOpaque(false);

        //设置头像标签
        label_2 = new JLabel(new ImageIcon("E:\\聊天软件\\untitled\\src\\imageSource\\4.png"));
        label_2.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
        label_2.setBounds(15, 15, 100, 100);
        panel_1.add(label_2);

        //初始暂存标签
        label_5 = new JLabel();
        label_6 = new JLabel();

        //设置昵称标签
        label_1 = new JLabel("");
        label_1.setBounds(130, 10, 100, 30);
        label_1.setFont(new Font("宋体", Font.PLAIN, 18));
        panel_1.add(label_1);

        list = new JList<String>(model);
        //设置每个列表的高
        list.setFixedCellHeight(20);
        list.setSelectionBackground(new Color(0xD8FF2F));
        list.addListSelectionListener(new ListSelectionListener() {
            @Override
            public void valueChanged(ListSelectionEvent e) {
                //打开一个聊天窗口
                if (e.getValueIsAdjusting()) {
                    for (int i = 0; i < model.size(); i++) {
                        if (model.get(i).equals(list.getSelectedValue())){
                            //获取id有错误
                            int ids = new sendServers(channel).getId((String) list.getSelectedValue());
                            if (ids!=0) {
                                new sendServers(channel).friendIsActive(ids);
                                new ChatFrame(ids, channel).setVisible(true);
                            }else{
                                System.out.println("好友不存在");
                            }
                        }
                    }
                }
            }
        });

        //初始化面板二
        panel_2 = new JScrollPane(list);
        panel_2.setBorder(BorderFactory.createTitledBorder("联系人"));
        panel_2.setLocation(0, 147);
        panel_2.setSize(new Dimension(295, 470));
        panel_2.getViewport().setOpaque(false);
        list.setOpaque(false);
        panel_2.setOpaque(false);

        //设置在线状态bBox();
        box = new JComboBox();
        box.addItem("✅在线");
        box.addItem("\uD83D\uDCBF隐身");
        box.addItem("\uD83D\uDCBB忙碌");
        box.addItem("❎离线");
        box.setBounds(200, 10, 70, 30);
        panel_1.add(box);

        //设置个性签名的标签
        label_4 = new JLabel("个性签名:");
        label_4.setFont(new Font("宋体", Font.PLAIN, 16));
        label_4.setForeground(Color.BLUE);
        label_4.setBounds(120, 50, 100, 20);
        panel_1.add(label_4);

        //设置文本
        field = new JTextField("");
        field.setBounds(120, 80, 160, 30);
        panel_1.add(field);

        label_3 = new JLabel("\uD83D\uDD0D");
        label_3.setForeground(Color.RED);
        label_3.setBounds(10, 122, 20, 20);
        panel_1.add(label_3);

        //设置搜索栏
        field_1 = new JTextField();
        field_1.setBounds(30, 120, 250, 25);
        panel_1.add(field_1);

        //对面板三进行初始化
        box_1 = new JComboBox();
        box_1.addItem("\uD83D\uDD12\uD83D\uDD28\uD83D\uDD13");
        box_1.addItem("修改密码");
        box_1.addItem("修改昵称");
        box_1.addItem("修改签名");
        box_1.setBounds(8, 20, 100, 25);
        panel_3.add(box_1);
        box_1.addItemListener(new ItemListener() {
            @Override
            public void itemStateChanged(ItemEvent e) {
                if ("修改签名".equals(box_1.getSelectedItem())) {
                    //执行一次
                    if (e.getStateChange() == ItemEvent.SELECTED) {
                        changeSignature changeSignature = new changeSignature(linkmen.this);
                        changeSignature.setVisible(true);
                        field.setText(changeSignature.jTextField.getText());
                        String signature = field.getText();
                        //存储签名的方法
                        new sendServers(channel).modifySignature(signature, id);
                    }
                }
                if ("修改密码".equals(box_1.getSelectedItem())) {
                    if (e.getStateChange() == ItemEvent.SELECTED) {
                        changePassword changePassword = new changePassword(linkmen.this);
                        changePassword.setVisible(true);
                        label_5.setText(changePassword.oldPassword.getText());
                        String oldPasswd = label_5.getText();
                        label_6.setText(new String(changePassword.newPassword.getPassword()));
                        String newPasswd = label_6.getText();
                        //进行验证
                        new sendServers(channel).verifyPasswd(oldPasswd, id,newPasswd);

                    }
                }
                if ("修改昵称".equals(box_1.getSelectedItem())) {
                    if (e.getStateChange() == ItemEvent.SELECTED) {
                        changeNickname changeNickname = new changeNickname(linkmen.this);
                        changeNickname.setVisible(true);
                        label_1.setText(changeNickname.jTextField.getText());
                        String nickname = label_1.getText();
                        //存储昵称
                        new sendServers(channel).modifyNickname(nickname, id);
                    }
                }
            }
        });
        //添加好友、删除好友
        box_2 = new JComboBox();
        box_2.addItem("\uD83D\uDC65");
        box_2.addItem("添加好友");
        box_2.addItem("删除好友");
        box_2.setBounds(170, 20, 100, 25);
        box_2.addItemListener(new ItemListener() {
            @Override
            public void itemStateChanged(ItemEvent e) {
                if ("添加好友".equals(box_2.getSelectedItem())) {
                    if (e.getStateChange() == ItemEvent.SELECTED) {
                        addFriend addFriend = new addFriend(linkmen.this);
                        addFriend.setVisible(true);
                        //读取要搜索的ID
                        String friendIds = addFriend.jTextField.getText();
                        //判断是否是字符串
                        if (judgeDigit(friendIds)){
                            int friendId = Integer.parseInt(friendIds);
                            //搜索数据库
                            new sendServers(channel).addFriendOperate(friendId,id,label_1.getText());
                        }else {
                            new tipFrame().init("输入参数错误");
                        }
                    }
                }
                if ("删除好友".equals(box_2.getSelectedItem())) {
                    if (e.getStateChange() == ItemEvent.SELECTED) {
                        delFriend delFriend = new delFriend(linkmen.this);
                        delFriend.setVisible(true);
                        //对其数据库进行删除操作
                        String friendIds = delFriend.TextField.getText();
                        //判断是否是字符串
                        if(judgeDigit(friendIds)){
                            int friendId = Integer.parseInt(friendIds);
                            //操作数据库
                            new sendServers(channel).delFriendOperate(friendId,id,label_1.getText());
                        }else{
                            new tipFrame().init("输入参数错误");
                        }
                    }
                }
            }
        });
        panel_3.add(box_2);
        //设置frame信息
        frame = new JFrame();
        //设置窗体信息
        frame.setTitle("腾讯QQ");
        //给窗体设置图片
        icon_1 = new ImageIcon("E:\\聊天软件\\untitled\\src\\imageSource\\3.png");
        frame.setIconImage(icon_1.getImage());
        icon = new ImageIcon("E:\\聊天软件\\untitled\\src\\imageSource\\5.png");
        label = new JLabel(icon);
        //获取窗口的第二层，将label放入
        frame.getLayeredPane().add(label, new Integer(Integer.MIN_VALUE));
        //获取frame的顶层容器,并设置为透明
        panel = (JPanel) frame.getContentPane();
        panel.setOpaque(false);
        frame.setLayout(null);
        frame.setLocation(750, 150);
        frame.setSize(287, 700);
        frame.setVisible(true);
        frame.setResizable(false);
        label.setBounds(0, 0, 287, 700);
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        frame.add(panel_1);
        frame.add(panel_2);
        frame.add(panel_3);
    }

    public void mian() {
        //初始化面板2并设置信息
        model = new DefaultListModel<>();
        for (int i = 0; i < fd.length; i++) {
            model.addElement(fd[i]);
        }
        init();
        //更新昵称和签名
        new sendServers(channel).update(id);
        //获取用户的昵称,和好友列表

        //设置签名和昵称字体初始样式和大小
        label_1.setFont(new Font("宋体", Font.PLAIN, 18));
        field.setFont(new Font("宋体", Font.PLAIN, 18));
    }

    //判断是否是数字
    private static boolean judgeDigit(String string){
        for (int i = 0; i < string.length(); i++) {
            if (!Character.isDigit(string.charAt(i))){
                return false;
            }
        }
        return true;
    }
}

4.tipFrame

提示操作状态窗口

package chat.Frame;

import chat.Frame.chat.linkmen;
import chat.Frame.operation.alterColumn.changeNickname;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class tipFrame extends JDialog {

    private Container container;
    //显示错误信息
    public JLabel label;
    //确认按钮
    private JButton button;

    public tipFrame(){

    }

    public void init(String msg){
        container = getContentPane();
        label = new JLabel(msg);
        label.setBounds(70,0,200,70);
        label.setFont(new Font("微软雅黑",Font.PLAIN,20));
        container.add(label);
        button = new JButton("确认");
        button.setBounds(35,50,140,40);
        container.add(button);
        setBounds(780,170,220,140);
        setLayout(null);
        setVisible(true);
        container.setBackground(new Color(0xD8FFD5));
        //提示窗口前置
        setAlwaysOnTop(true);
        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                tipFrame.this.dispose();
            }
        });
    }
}