0067 练习

import java.util.Scanner;
/*
    在main方法中启动两个线程
    第一个线程循环随机打印100以内的整数
    直到第二个线程从键盘读取"Q"命令 停止
 */
public class ThreadExe {
    public static void main(String[] args) {
        A a = new A();
        B b = new B(a);
        b.start();
        a.start();
    }
}

class A extends Thread{
    private boolean loop = true;
    @Override
    public void run() {
        while (loop){
            System.out.println((int)(Math.random() * 100 + 1));//随机输出1-100
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        System.out.println("A线程退出");
    }
    public void setLoop(boolean loop){//修改loop
        this.loop = loop;
    }
}

class B extends Thread{
    private A a;
    Scanner scanner = new Scanner(System.in);

    public B(A a) {//传入A对象
        this.a = a;
    }

    @Override
    public void run() {
        while (true) {
            System.out.println("请输入Q退出循环");
            char key = scanner.next().toUpperCase().charAt(0);
            if (key == 'Q'){
                a.setLoop(false);//a线程退出
                System.out.println("B线程退出");
                break;//b线程退出
            }
        }
    }
}

/*
    两个用户分别从同一张卡里取钱，总10000元
    每次都取1000，当余额不足时停止取款
 */
public class ThreadExe02 {
    public static void main(String[] args) {
        M m = new M();
        Thread m1 = new Thread(m);
        Thread m2 = new Thread(m);
        m1.start();
        m2.start();
    }
}
//共享资源，使用实现Runnable接口方式
class M implements Runnable{
    private static int money = 10000;
    @Override
    public void run() {
        while (true){
            synchronized (this) {
                if (money < 1000) {
                    System.out.println("余额不足");
                    break;
                }
                money -= 1000;
                System.out.println(Thread.currentThread().getName() + "取出了1000，余额为" + money);
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

/*
    主线程每隔1秒输出1次hello，共10次
    当输出到第五次hello时，启动子线程，每隔1s输出hi，输出10次后退出
    主线程继续输出hello，直到退出
 */
public class ThreadExe03 {
    public static void main(String[] args) throws InterruptedException {
        Thread h = new Thread(new H());

        for (int i = 1;i <= 10;i++){
            System.out.println("hello," + i);
            if (i == 5){
                h.start();
                h.join();
            }
            Thread.sleep(1000);
        }
    }
}
class H implements Runnable{
    private int count = 0;
    @Override
    public void run() {
        while (true){
            System.out.println("hi," + (++count));
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            if (count == 10){
                break;
            }
        }
    }
}