public class DealLockTest implements Runnable { static String i = new String(); static String j = new String(); private String str = null; public DealLockTest(String str) { this.str = str; } public static void main(String[] args) { new Thread(new DealLockTest("i")).start(); new Thread(new DealLockTest("j")).start(); } public void run() { if (str.equals("i")) { synchronized (i) { System.out.println(Thread.currentThread().getName()+":"+"i"); Thread.yield(); synchronized (j) { System.out.println("i is over"); } } } else { synchronized (j) { System.out.println(Thread.currentThread().getName()+":"+"j"); Thread.yield(); synchronized (i) { System.out.println("j is over"); } } } } }
线程何时发生死锁呢?
最简单的情况是当1个线程获得了资源A,当它再获得资源B时,就可以完成任务.而在它获得了A的时候
另一个线程获得了资源B,去抢资源A..此时,就发生了死锁
前提(共享资源(static),加锁(synchronized)).