传说有一本江湖罕见的武功秘籍，该书珍藏在主持大师手中。一天大师盛情邀请江湖好汉前来观摩该书，但是一次只能有一个人来看。该怎么办呢？用synchronized来实现吗？都用臭了，算了。用下李狗(Doug Lea)写的Lock吧。实现很简单，首先获得一个锁实例Lock lock = new ReentrantLock();接着获得一把锁:lock.lock();观摩该书中。。。lock.unlock(

add cast for null in overloaded methods (#636) (PR #637) (77cee15)add correct type propagation for check-cast and move instructions (#401) (7bd1752)add labels from NOP instructions in fallback mode (#