/guava/guava/src/com/google/common/util/concurrent/CycleDetectingLockFactory.java
this.lockGraphNode = Preconditions.checkNotNull ( lockGraphNode ) ;
private final CycleDetectingReentrantWriteLock writeLock; private final LockGraphNode lockGraphNode; private CycleDetectingReentrantReadWriteLock(LockGraphNode lockGraphNode, boolean fair) { super(fair); this.readLock = new CycleDetectingReentrantReadLock(this); this.writeLock = new CycleDetectingReentrantWriteLock(this); <extra_id_0> } @Override public ReadLock readLock() { return readLock; } @Override