死锁的例子
作者:互联网
什么是死锁?
多个线程互相抱着对方的资源,然后形成僵持
产生死锁的四个必要条件:
(1)互斥条件:一个资源每次只能被一个进程使用
(2)请求与保持条件:一个进程因请求资源而阻塞时,对已获得的资源保持不放
(3)不剥夺条件:进程已获得的资源,在未使用之前,不能强行剥夺
(4)循环等待条件:若干进程之间形成一种头尾相连的循环等待资源关系
上面列出的四个必要条件,我们只要想办法破其中任意或多个条件,就可以避免死锁的产生
/**
* @author DB
* @title: DeadLock
* @projectName XianCheng
* @description: 死锁问题
* @date 2021/11/14 22:25
*/
public class DeadLock {
public static void main(String[] args) {
Makeup g1 = new Makeup(0, "白雪公主");
Makeup g2 = new Makeup(1, "灰姑凉");
g1.start();
g2.start();
}
}
//口红
class LispStick{
}
//镜子
class Mirror{
}
class Makeup extends Thread{
//需要的资源只有一份,用static 关键字来保证只有一份
static LispStick lispStick = new LispStick();
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();
}
}
private void makeup() throws InterruptedException {
if (choice == 0){
synchronized (lispStick){
System.out.println(this.girlName + "获得口红的锁");
Thread.sleep(1000);
synchronized (mirror){
System.out.println(this.girlName + "获得镜子的锁");
}
}
}else {
synchronized (mirror){
System.out.println(this.girlName + "获得镜子的锁");
Thread.sleep(1000);
synchronized (lispStick){
System.out.println(this.girlName + "获得口红的锁");
}
}
}
}
}
程序死锁,直接卡死
标签:girlName,Makeup,choice,死锁,例子,static,println 来源: https://blog.csdn.net/qq_49005459/article/details/121325385