/**
     * The synchronization state.
     */
    private volatile int state;

    /**
     * Returns the current value of synchronization state.
     * This operation has memory semantics of a {@code volatile} read.
     * @return current state value
     */
    protected final int getState() {
        return state;
    }
 
    /**
     * Sets the value of synchronization state.
     * This operation has memory semantics of a {@code volatile} write.
     * @param newState the new state value
     */
    protected final void setState(int newState) {
        state = newState;
    }
    /**
     * Atomically sets synchronization state to the given updated
     * value if the current state value equals the expected value.
     * This operation has memory semantics of a {@code volatile} read
     * and write.
     *
     * @param expect the expected value
     * @param update the new value
     * @return {@code true} if successful. False return indicates that the actual
     *         value was not equal to the expected value.
     */
    protected final boolean compareAndSetState(int expect, int update) {
        // See below for intrinsics setup to support this
        return unsafe.compareAndSwapInt(this, stateOffset, expect, update);
    }

//自定義鎖（不可重入）（獨(dú)占鎖）（條件變量）
class MyLock implements Lock{
    //內(nèi)部類，AQS同步器類
    class MySync extends AbstractQueuedSynchronizer{
        @Override
        protected boolean tryAcquire(int arg) {
            if (compareAndSetState(0,1)){
                System.out.println("獲得鎖成功");
                //加上了鎖,并設(shè)置owner為當(dāng)前線程
                setExclusiveOwnerThread(Thread.currentThread());
                return true;
            }
            System.out.println("獲得鎖失敗");
            return false;
        }
 
        @Override
        protected boolean tryRelease(int arg) {
            setExclusiveOwnerThread(null);
            setState(0);
            return true;
        }
 
        @Override
        protected boolean isHeldExclusively() {
            return getState() == 1;
        }
 
        public Condition newCondition(){
            return new ConditionObject();
        }
    }
 
    private MySync mySync = new MySync();
 
    @Override //加鎖（不成功進(jìn)入阻塞隊(duì)列等待）
    public void lock() {
        mySync.acquire(1);
    }
 
    @Override //加鎖可打斷
    public void lockInterruptibly() throws InterruptedException {
        mySync.acquireInterruptibly(1);
    }
 
    @Override //加鎖(不成功不會(huì)進(jìn)入阻塞隊(duì)列等待，可以去做其他事情)
    public boolean tryLock() {
        return mySync.tryAcquire(1);
    }
 
    @Override //嘗試加鎖 帶時(shí)間
    public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
        return mySync.tryAcquireNanos(1,unit.toNanos(time));
    }
 
    @Override //釋放鎖
    public void unlock() {
        mySync.release(1);
    }
 
    @Override //創(chuàng)建條件變量
    public Condition newCondition() {
        return mySync.newCondition();
    }
}