检测当前线程是否在指定对象上拥有锁：holdsLock()

public static native boolean holdsLock(Object object) 方法的作用是当currentThread在指定的对象上保持锁定时，才返回true。 样例代码：

public class HoldsLockTest { public static void main(String[] args) { Thread.currentThread(); System.out.println("A " + Thread.holdsLock(HoldsLockTest.class)); synchronized (HoldsLockTest.class) { System.out.println("B " + Thread.holdsLock(HoldsLockTest.class)); } System.out.println("C "+ Thread.holdsLock(HoldsLockTest.class)); HoldsLockTest test1 = new HoldsLockTest(); HoldsLockTest test2 = new HoldsLockTest(); System.out.println("D test1：" + Thread.holdsLock(test1) + " test2：" + Thread.holdsLock(test2)); synchronized (test1) { System.out.println("E test1：" + Thread.holdsLock(test1) + " test2：" + Thread.holdsLock(test2)); } System.out.println("F test1：" + Thread.holdsLock(test1) + " test2：" + Thread.holdsLock(test2)); } }

运行结果：

A false B true C false D test1：false test2：false E test1：true test2：false F test1：false test2：false