package qzy.thread.deadLock;/*** @描述模拟死锁** 形成死锁的四个必要条件是什么** 1.互斥条件：线程(进程)对于所分配到的资源具有排它性，即一个资源只能被一个线程(进程)占用，直到被该线程(进程)释放* 2.请求与保持条件：一个线程(进程)因请求被占用资源而发生阻塞时，对已获得的资源保持不放。* 3.不剥夺条件：线程(进程)已获得的资源在末使用完之前不能被其他线程强行剥夺，只有自己使用完毕后才释放资源。* 4.循环等待条件：当发生死锁时，所等待的线程(进程)必定会形成一个环路（类似于死循环），造成永久阻塞*** @创建人 joy_qiu* @创建时间 * @修改人和其它信息*/
public class DeadLockDemo {private static Object o1 = new Object();private static Object o2 = new Object();public static void main(String[] args) {new Thread(() -> {synchronized (o1){System.out.println(Thread.currentThread()+":获取到o1的锁");try{Thread.sleep(2000);} catch (InterruptedException e) {e.printStackTrace();}System.out.println(Thread.currentThread()+":等待获取o2的锁");synchronized (o2){System.out.println(Thread.currentThread()+":获取到o2的锁");}}},"线程1").start();new Thread(() -> {synchronized (o2){System.out.println(Thread.currentThread()+":获取到o2的锁");try{Thread.sleep(2000);} catch (InterruptedException e) {e.printStackTrace();}System.out.println(Thread.currentThread()+":等待获取o1的锁");synchronized (o1){System.out.println(Thread.currentThread()+":获取到o1的锁");}}},"线程2").start();}
}/*** 解决死锁的例子*/
class UnDeadLock{private static Object o1 = new Object();private static Object o2 = new Object();public static void main(String[] args) {new Thread(() -> {synchronized (o1){System.out.println(Thread.currentThread()+":获取到o1的锁");try{Thread.sleep(2000);} catch (InterruptedException e) {e.printStackTrace();}System.out.println(Thread.currentThread()+":等待获取o2的锁");synchronized (o2){System.out.println(Thread.currentThread()+":获取到o2的锁");}}},"线程1").start();new Thread(() -> {synchronized (o1){System.out.println(Thread.currentThread()+":获取到o1的锁");try{Thread.sleep(2000);} catch (InterruptedException e) {e.printStackTrace();}System.out.println(Thread.currentThread()+":等待获取o2的锁");synchronized (o2){System.out.println(Thread.currentThread()+":获取到o2的锁");}}},"线程2").start();}
}