线程练习题

习题1

(1)在main方法中启动两个线程
(2)第1个线程循环随机打印100以内的整数(3)直到第2个线程从键盘读取了“Q”命令。

代码

package program;

import java.util.Random;
import java.util.Scanner;

public class Homewor01 {
    public static void main(String[] args) {
        H1 h1 = new H1();
        Thread thread = new Thread(h1);
        thread.start();

        H2 h2 = new H2(h1);
        Thread thread2 = new Thread(h2);
        thread2.start();
    }
}

class H1 implements Runnable{
    private boolean loop = true;
    public void print() {
    }

    @Override
    public void run() {
        while (loop) {
            Random random = new Random();
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    throw new RuntimeException(e);
                }
                System.out.println( random.nextInt(100));
        }
    }

    public void setLoop(boolean loop) {
        this.loop = loop;
    }

    public boolean isLoop() {
        return loop;
    }
}

class H2 implements Runnable{
    private boolean loop = true;
    private H1 h1;
    public void conrolH1() {
        while (true){
            Scanner scanner = new Scanner(System.in);
            System.out.println("请输入字符(Q)：");
            String str = scanner.next();
            if (str.toUpperCase().charAt(0) == 'Q') {
                System.out.println("H2结束任务");
                h1.setLoop(false);
                System.out.println(h1.isLoop());
                loop = false;
                break;
            }
        }
    }

    @Override
    public void run() {
        while (loop) {
            conrolH1();
        }
    }

    public H2(H1 h1) {
        this.h1 = h1;
    }
}

运行结果

习题2

(1)有2个用户分别从同一个卡上取钱(总额:10000)(2)每次都取1000,当余额不足时，就不能取款了(3)不能出现超取现象

代码

package program;

public class Homewor02 {
    public static void main(String[] args) {
        J j = new J();
        j.start();
        J j2 = new J();
        j2.start();
    }
}

class J extends Thread {
    private static double money = 10000;
    private boolean loop = true;
    public synchronized void withdraw() {
        if (money <= 0){
            System.out.println("没钱可取了，请充值！！！");
            loop = false;
            return;
        }
        try {
            Thread.sleep(500);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        money -= 1000;
        System.out.println(Thread.currentThread().getName() + "取了1000元 剩余" + money) ;

    }
    @Override
    public void run() {
        while (loop) {
            withdraw();
        }
    }
}

运行结果