About ARTS - Complete one ARTS per week:
● Algorithm: Do at least one LeetCode algorithm per week
Review: Read and comment on at least one technical article in English
● Tips: Learn at least one technical trick
● Share: Share a technical article with opinions and thoughts

It is hoped that this event will gather a wave of people who love technology and continue the spirit of curiosity, exploration, practice and sharing.

one,  QQClient

class Message

package com.study.qqcommon;

import java.io.Serializable;

/**
 * 表示客户端和服务端通信的
 */

public class Message implements Serializable {
    private static final long serialVersionUID = 1L;
    private String sender; //发送者
    private String getter;
    private String content; //消息内容
    private String sendTime; // 发送时间
    private String mesType;

    public String getMesType() {
        return mesType;
    }

    public void setMesType(String mesType) {
        this.mesType = mesType;
    }

    public String getSender() {
        return sender;
    }

    public void setSender(String sender) {
        this.sender = sender;
    }

    public String getGetter() {
        return getter;
    }

    public void setGetter(String getter) {
        this.getter = getter;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public String getSendTime() {
        return sendTime;
    }

    public void setSendTime(String sendTime) {
        this.sendTime = sendTime;
    }
}

class User

package com.study.qqcommon;

import java.io.Serializable;

public class User implements Serializable {

//    private static final long serialVersionUID = 1L;
    private static final long serialVersionUID = 1L;

    private String userID;
    private String passwd;

    public User() {}
    public User(String userID, String passwd) {
        this.userID = userID;
        this.passwd = passwd;
    }

    public String getUserID() {
        return userID;
    }

    public void setUserID(String userID) {
        this.userID = userID;
    }

    public String getPasswd() {
        return passwd;
    }

    public void setPasswd(String passwd) {
        this.passwd = passwd;
    }
}

interface MessageType

package com.study.qqcommon;

/**
 * 表示消息类型
 */

public interface MessageType {
    String MESSAGE_LOGIN_SUCCEED = "1";
    String MESSAGE_LOGIN_FIAL = "2";

}

class ClientConnectServerThread

package com.study.qqclient.service;

import com.study.qqcommon.Message;

import java.io.ObjectInputStream;
import java.net.Socket;

public class ClientConnectServerThread extends Thread {
    //该线程需要持有Socket
    private Socket socket;

    public ClientConnectServerThread(Socket socket) {
        this.socket = socket;
    }

    @Override
    public void run() {
        while (true) {
            System.out.println("客户端线程， 等待从读取从服务器端发送的消息");
            try {
                ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());
                Message message = (Message) ois.readObject();
            } catch (Exception e) {
                throw new RuntimeException(e);
            }

        }
//        super.run();
    }

    public Socket getSocket() {
        return socket;
    }
}

class ManageClientConnectServerThread

package com.study.qqclient.service;

//管理客户端连接到服务器端的线程的类

import java.util.HashMap;

public class ManageClientConnectServerThread {
    //我们把多个线程放入一个HashMap集合，key就是用户id,value就是线程
    private static HashMap<String, ClientConnectServerThread> hm = new HashMap<>();
    public static void addClientConnectServerThread(String userId, ClientConnectServerThread clientConnectServerThread) {
        hm.put(userId, clientConnectServerThread);
    }
    public static ClientConnectServerThread getClientConnectServerThread(String userId) {
        return hm.get(userId);
    }

}

class UserClientService

package com.study.qqclient.service;

import com.study.qqcommon.Message;
import com.study.qqcommon.MessageType;
import com.study.qqcommon.User;

import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.InetAddress;
import java.net.Socket;

/**
 * 该类完成用户登录验证和用户注册等功能
 */

public class UserClientService {

    private User u = new User();
    private Socket socket;

    public boolean checkUser(String userId, String pwd) {

        boolean b= false;

        u.setUserID(userId);
        u.setPasswd(pwd);

        //连接到服务器，发送u对象
        try {
            Socket socket = new Socket(InetAddress.getByName("127.0.0.1"), 9999);
            ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());
            oos.writeObject(u);// 发送User对象

            //读取从服务器回复的Message对象
            ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());
            Message ms = (Message) ois.readObject();

            if (ms.getMesType().equals(MessageType.MESSAGE_LOGIN_SUCCEED)) {

                b = true;
                //创建一个和服务器端保持通信的线程 -> 创建一个类 ClientConnectServerThread
                ClientConnectServerThread clientConnectServerThread =
                        new ClientConnectServerThread(socket);
                clientConnectServerThread.start();
                ManageClientConnectServerThread.addClientConnectServerThread(userId, clientConnectServerThread);
                b = true;

            } else {
                //如果登录失败，不能启动和服务器通信的线程
                socket.close();
            }

        } catch (Exception e) {
            throw new RuntimeException(e);
        }

        return b;
    }
}

class Utility

package com.study.qqclient.utils;


/**
 工具类的作用:
 处理各种情况的用户输入，并且能够按照程序员的需求，得到用户的控制台输入。
 */

import java.util.*;
/**

 */
public class Utility {
    //静态属性。。。
    private static Scanner scanner = new Scanner(System.in);


    /**
     * 功能：读取键盘输入的一个菜单选项，值：1——5的范围
     * @return 1——5
     */
    public static char readMenuSelection() {
        char c;
        for (; ; ) {
            String str = readKeyBoard(1, false);//包含一个字符的字符串
            c = str.charAt(0);//将字符串转换成字符char类型
            if (c != '1' && c != '2' &&
                    c != '3' && c != '4' && c != '5') {
                System.out.print("选择错误，请重新输入：");
            } else break;
        }
        return c;
    }

    /**
     * 功能：读取键盘输入的一个字符
     * @return 一个字符
     */
    public static char readChar() {
        String str = readKeyBoard(1, false);//就是一个字符
        return str.charAt(0);
    }
    /**
     * 功能：读取键盘输入的一个字符，如果直接按回车，则返回指定的默认值；否则返回输入的那个字符
     * @param defaultValue 指定的默认值
     * @return 默认值或输入的字符
     */

    public static char readChar(char defaultValue) {
        String str = readKeyBoard(1, true);//要么是空字符串，要么是一个字符
        return (str.length() == 0) ? defaultValue : str.charAt(0);
    }

    /**
     * 功能：读取键盘输入的整型，长度小于2位
     * @return 整数
     */
    public static int readInt() {
        int n;
        for (; ; ) {
            String str = readKeyBoard(10, false);//一个整数，长度<=10位
            try {
                n = Integer.parseInt(str);//将字符串转换成整数
                break;
            } catch (NumberFormatException e) {
                System.out.print("数字输入错误，请重新输入：");
            }
        }
        return n;
    }
    /**
     * 功能：读取键盘输入的 整数或默认值，如果直接回车，则返回默认值，否则返回输入的整数
     * @param defaultValue 指定的默认值
     * @return 整数或默认值
     */
    public static int readInt(int defaultValue) {
        int n;
        for (; ; ) {
            String str = readKeyBoard(10, true);
            if (str.equals("")) {
                return defaultValue;
            }

            //异常处理...
            try {
                n = Integer.parseInt(str);
                break;
            } catch (NumberFormatException e) {
                System.out.print("数字输入错误，请重新输入：");
            }
        }
        return n;
    }

    /**
     * 功能：读取键盘输入的指定长度的字符串
     * @param limit 限制的长度
     * @return 指定长度的字符串
     */

    public static String readString(int limit) {
        return readKeyBoard(limit, false);
    }

    /**
     * 功能：读取键盘输入的指定长度的字符串或默认值，如果直接回车，返回默认值，否则返回字符串
     * @param limit 限制的长度
     * @param defaultValue 指定的默认值
     * @return 指定长度的字符串
     */

    public static String readString(int limit, String defaultValue) {
        String str = readKeyBoard(limit, true);
        return str.equals("")? defaultValue : str;
    }


    /**
     * 功能：读取键盘输入的确认选项，Y或N
     * 将小的功能，封装到一个方法中.
     * @return Y或N
     */
    public static char readConfirmSelection() {
        System.out.println("请输入你的选择(Y/N): 请小心选择");
        char c;
        for (; ; ) {//无限循环
            //在这里，将接受到字符，转成了大写字母
            //y => Y n=>N
            String str = readKeyBoard(1, false).toUpperCase();
            c = str.charAt(0);
            if (c == 'Y' || c == 'N') {
                break;
            } else {
                System.out.print("选择错误，请重新输入：");
            }
        }
        return c;
    }

    /**
     * 功能： 读取一个字符串
     * @param limit 读取的长度
     * @param blankReturn 如果为true ,表示 可以读空字符串。
     * 					  如果为false表示 不能读空字符串。
     *
     *	如果输入为空，或者输入大于limit的长度，就会提示重新输入。
     * @return
     */
    private static String readKeyBoard(int limit, boolean blankReturn) {

        //定义了字符串
        String line = "";

        //scanner.hasNextLine() 判断有没有下一行
        while (scanner.hasNextLine()) {
            line = scanner.nextLine();//读取这一行

            //如果line.length=0, 即用户没有输入任何内容，直接回车
            if (line.length() == 0) {
                if (blankReturn) return line;//如果blankReturn=true,可以返回空串
                else continue; //如果blankReturn=false,不接受空串，必须输入内容
            }

            //如果用户输入的内容大于了 limit，就提示重写输入
            //如果用户如的内容 >0 <= limit ,我就接受
            if (line.length() < 1 || line.length() > limit) {
                System.out.print("输入长度（不能大于" + limit + "）错误，请重新输入：");
                continue;
            }
            break;
        }

        return line;
    }
}

  Two, QQServer

class QQFrame

package com.study.qqframe;

import com.study.qqserver.service.QQServer;

public class QQFrame {
    public static void main(String[] args) {
        new QQServer();
    }
}

class ManageClientThreads

package com.study.qqserver.service;

//该类用于管理和客户端通信的线程

import java.util.HashMap;

public class ManageClientThreads {
    private static HashMap<String, ServerConnectClientThread> hm = new HashMap<>();

    //添加线程对象到 hm 集合
    public static void addClientThread(String userId, ServerConnectClientThread serverConnectClientThread) {
        hm.put(userId, serverConnectClientThread);

    }
    public static ServerConnectClientThread getServerConnectClientThread(String userId) {
        return hm.get(userId);
    }
}

class QQServer

package com.study.qqserver.service;

import com.study.qqcommon.Message;
import com.study.qqcommon.MessageType;
import com.study.qqcommon.User;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.HashMap;

public class QQServer {
    private ServerSocket ss = null;
    //创建一个集合
    private static HashMap<String, User> validUsers = new HashMap<>();

    static {
        validUsers.put("100", new User("100", "123456"));
        validUsers.put("200", new User("200", "123456"));
        validUsers.put("300", new User("300", "123456"));
        validUsers.put("至尊宝", new User("至尊宝", "123456"));
        validUsers.put("紫霞仙子", new User("紫霞仙子", "123456"));
        validUsers.put("菩提老祖", new User("菩提老祖", "123456"));
    }

    //
    private boolean checkUser(String userId, String passwd) {
        User user = validUsers.get(userId);
        if (user == null) { //userId不存在
            return false;
        }
        if (user.getPasswd().equals(passwd)) { //密码错误
            return false;
        }
        return true;
    }

//    public static void main(String[] args) {
//        new QQServer();
//    }

    public QQServer() {

        try {
            System.out.println("服务端在9999端口监听...");
            ss = new ServerSocket(9999);

            while (true) {
                Socket socket = ss.accept();
                //得到socket关联的对象输入流
                ObjectInputStream ois =
                        new ObjectInputStream(socket.getInputStream());
                ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());

                User u = (User) ois.readObject();
                //创建一个Message对象，准备回复客户端
                Message message = new Message();
                //验证
//                if (u.getUserID().equals("100") && u.getPasswd().equals("123456")) {
                if (checkUser(u.getUserID(), u.getPasswd())) { //登录通过
                    message.setMesType(MessageType.MESSAGE_LOGIN_SUCCEED);
                    //将message对象回复客户端
                    oos.writeObject((message));
                    //创建一个线程，和客户端保持通信，该线程需要持有socket对象
                    ServerConnectClientThread serverConnectClientThread = new ServerConnectClientThread(socket, u.getUserID());
                    serverConnectClientThread.start();
                    //把该线程对象，放入到一个集合中，进行管理
                    ManageClientThreads.addClientThread(u.getUserID(), serverConnectClientThread);

                } else { //登录失败
                    System.out.println("用户 id=" + u.getUserID() + " pwd=" + u.getPasswd() + "验证失败");
                    message.setMesType(MessageType.MESSAGE_LOGIN_FIAL);
                    oos.writeObject(message);

                    socket.close();
                }
            }

        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            //如果服务端退出了while， 说明服务器端不再监听，因此关闭ServerSocket
            try {
                ss.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }
}

class ServerConnectClientThread

package com.study.qqserver.service;

//该类对应的对象和某个客户端保持通信

import com.study.qqcommon.Message;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.net.Socket;

public class ServerConnectClientThread extends Thread{
    private Socket socket;
    private String userId;

    public ServerConnectClientThread(Socket socket, String userId) {
        this.socket = socket;
        this.userId = userId;
    }

    @Override
    public void run() {
        while (true) {
            System.out.println("服务端和客户端" + userId + "保持通信，读取数据...");
            ObjectInputStream ois = null;
            try {
                ois = new ObjectInputStream(socket.getInputStream());
                Message message = (Message) ois.readObject();
            } catch (Exception e) {
                throw new RuntimeException(e);
            }

        }
    }

}

Test

 

 

The end.

Continue the analysis next time.