其他
用 Java 写了一个类QQ界面聊天小项目，可在线聊天！
责编：Java就该这么学 | 来源： AC路上
链接：blog.csdn.net/weixin_44048140/article/details/109612049
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
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
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();
}
});
}
}
5.运行例图
1.登录界面
注册账号和忘记密码没有添加事件现在就是个摆设
2.联系人界面
这里面的所有功能都可以使用
3.聊天界面
4.通信的过程
5.修改操作
6.好友的操作
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