A module interface specification must be written for each module. It must be formal and provide a black box picture of each module.
一份组件接口说明必须适用于每一个组件。它必须很正规，而且提供每个组件的黑箱图片。
2
This change did introduce fuzziness into the picture, but this fuzziness is more of a reflection of reality versus a mistake in the UML 2 specification.