This article analyses shortage in CBO of C &K metrics suit. As fan-in and fan-out coupling are not divided in CBO,this article presents a suit of object oriented software fan-in coupling metrics.

• 针对C &K度量组中耦合度量指标(CBO)没有区分扇入耦合和扇出耦合对软件质量影响的情况,提出了一组正交的对象间扇入耦合度量组,并对该度量组中各度量指标对软件质量的指示作用进行了讨论。