public V get(K key, boolean isUpdateLastAccess) {
	CacheObj<K, V> co;
	lock.lock();
	try {
		co = getWithoutLock(key);
	} finally {
		lock.unlock();
	}

	// 未命中
	if (null == co) {
		missCount.increment();
		return null;
	} else if (false == co.isExpired()) {
		hitCount.increment();
		return co.get(isUpdateLastAccess);
	}

	// 过期，既不算命中也不算非命中
	remove(key, true);
	return null;
}

public void put(K key, V object, long timeout) {
	lock.lock();
	try {
		putWithoutLock(key, object, timeout);
	} finally {
		lock.unlock();
	}
}

private void remove(K key, boolean withMissCount) {
	lock.lock();
	CacheObj<K, V> co;
	try {
		co = removeWithoutLock(key, withMissCount);
	} finally {
		lock.unlock();
	}
	if (null != co) {
		onRemove(co.key, co.obj);
	}
}