Metrics on a package

Overview

Metrics calculated on a package are used to obtain:

· local counting of the package's items: Only items defined directly on the package are counted

· global counting of the package's items: All the package's items are counted, by dealing recursively with sub-items

· elaborated metrics

· the list of non-standard items

Counting items

These metrics are used to calculate:

· the number of modeling units (namespaces)

· the number of packages

· the number of classes

· the number of interfaces

· the number of components

· the number of actors

· the number of use cases

· the number of nodes

· the number of types

· the number of signals

· the number of enumerations

· the number of collaborations

· the number of artifacts

· the number of parent packages (NOP)

· the number of child packages (NOC)

· the number of packages used

· the number of packages which use this package

Figure 13 - Example of metrics on a package

Elaborated metrics

These metrics are used to calculate:

· the average number of attributes per class (NOA)

· the average number of operations per class (NOM)

· the degree of responsibility (CR)

· instability (I)

· abstraction (A)

· the balance between abstraction and instability (DMS)

· the cohesion between classes in the package (CCRC)

· the coupling between the package's classes (CBO)

Figure 14 - Example of metrics on a class

Non-standard items

According to the values defined for each specific metric when configuring Objecteering Metrics, a table resumes the set of items which do not satisfy the quality criteria defined by the user. For each item, a cross is used to symbolize those metrics which render the item "non-standard".

For each item, a hypertext link is used to rapidly open the file containing the set of its metrics. Another hypertext link allows you to access the on-line help with the description of the metric in question.

Figure 15 - Non-standard element in a package