/guava/guava/src/com/google/common/util/concurrent/CycleDetectingLockFactory.java
lockStateChanged ( readWriteLock ) ;
@Override public boolean tryLock(long timeout, TimeUnit unit) throws InterruptedException { aboutToAcquire(readWriteLock); try { return super.tryLock(timeout, unit); } finally { <extra_id_0> } } @Override public void unlock() { try { super.unlock();