What are different object oriented metrics in software measurement?

Object Oriented Metrics

Lines of code and Function point metrics can be used for object oriented projects but they do not provide enough granularity for schedule. Some object oriented metrics are as follows:

- Number of scenario scripts
A scenario script describes the interaction between user and application. It is directly related to application size and number of test cases developed to exercise the system.

- Number of key classes
Key classes are independent components. The number of key classes is the indication of the amount of effort that is required to develop the software and it also indicates the potential amount of reuse applied during system development. The key classes are directly related to problem domain.

- Number of support classes
Support classes are not directly related to problem domain. Support classes can be developed for key class. Number of support classes indicates amount of effort required to develop software and potential amount of reuse to be applied.

- Number of subsystems
Subsystem is gathering of classes supporting a function visible to the end user. A schedule is laid out in which work on subsystem is partitioned.

- Average number of support classes per key class
Estimation becomes easy and simplified if average number of support classes per key class is known.

As database grows, relationships between object oriented measures and project measures provides metrics for project estimation.