死锁

package com.syn;

//死锁:多个线程互相抱着对方需要的资源，然后形成僵持
public class DeadLock {
    public static void main(String[] args) {
        Makeup g1 = new Makeup(0,"灰姑凉");
        Makeup g2 = new Makeup(1,"白雪公主");

        g1.start();
        g2.start();

    }
}


//口红
class Lipstick{

}

//镜子
class Mirror{

}

class Makeup extends Thread{
    //需要的资源只有一份，用static来保证只有一份
    static Lipstick lipstick = new Lipstick();
    static Mirror mirror = new Mirror();

    int choice;//选择
    String girlName;//使用化妆品的人

    Makeup(int choice,String girlName){
        this.choice = choice;
        this.girlName = girlName;
    }

    @Override
    public void run() {
        //化妆
        try {
            makeup();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    //化妆，相互持有对方的锁，就是需要拿到对方的锁
    private void makeup() throws InterruptedException {
        if(choice == 0){
            synchronized (lipstick){//获得口红的锁
                System.out.println(this.girlName+"获得口红的锁");
                Thread.sleep(1000);

                synchronized (mirror){//一秒钟后想获得镜子的锁
                    System.out.println(this.girlName+"获得镜子的锁");
                }
            }
        }else {
            synchronized (mirror){//获得镜子的锁
                System.out.println(this.girlName+"获得镜子的锁");
                Thread.sleep(2000);

                synchronized (lipstick){//2秒钟后想获得口红的锁
                    System.out.println(this.girlName+"获得口红的锁");
                }
            }
        }
    }

}

解除死锁：

package com.syn;

//死锁:多个线程互相抱着对方需要的资源，然后形成僵持
public class DeadLock {
    public static void main(String[] args) {
        Makeup g1 = new Makeup(0,"灰姑凉");
        Makeup g2 = new Makeup(1,"白雪公主");

        g1.start();
        g2.start();

    }
}


//口红
class Lipstick{

}

//镜子
class Mirror{

}

class Makeup extends Thread{
    //需要的资源只有一份，用static来保证只有一份
    static Lipstick lipstick = new Lipstick();
    static Mirror mirror = new Mirror();

    int choice;//选择
    String girlName;//使用化妆品的人

    Makeup(int choice,String girlName){
        this.choice = choice;
        this.girlName = girlName;
    }

    @Override
    public void run() {
        //化妆
        try {
            makeup();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    //化妆，相互持有对方的锁，就是需要拿到对方的锁
    private void makeup() throws InterruptedException {
        if(choice == 0){
            synchronized (lipstick){//获得口红的锁
                System.out.println(this.girlName+"获得口红的锁");
                Thread.sleep(1000);
            }
            synchronized (mirror){//一秒钟后想获得镜子的锁
                System.out.println(this.girlName+"获得镜子的锁");
            }
        }else {
            synchronized (mirror){//获得镜子的锁
                System.out.println(this.girlName+"获得镜子的锁");
                Thread.sleep(2000);
            }
            synchronized (lipstick){//2秒钟后想获得口红的锁
                System.out.println(this.girlName+"获得口红的锁");
            }
        }
    }

}