To measure software products, so-called software metrics are used that quantify different properties of software products and processes. When measuring software, an object-oriented metric takes into account the grouping of data structures and the methods applicable to them to form an object, its relationships to other objects, and the general structural characteristics of object-oriented programming
(OOP). The Coupling Between Objects (CBO) metric, which can be interpreted as an object-oriented software metric according to CBO, belongs to the group of measures that are based on aggregation hierarchies and specifically define a measure of the relationships between classes. Other object-oriented software metrics include Weighted Methods for Class (WMC), Response for a Class (RFC), Depth of Inheritance Tree (DIT), Number of Children (NOC), and Lack of Cohesion in Methods
theCBO is equal to the number of class(es) coupled to the class under consideration
, wherecoupling refers to a class using instance
variables-that is,variables of an instantiated class-and the methods of another
class.However, classes developed by inheritance are not taken into account, nor is the number of methods used.class
diagramshown defines the static parts of a system of classes with their associations and methods.
example class diagram:
CBO(A)=4 and CBO(B)=1 and CBO(F)=0, CBO(H)=0Application. Mainly in the context of software testability and maintainability. This is based on the consideration that the greater the number of couplings between a class and other classes, the more complex it is to understand and handle. The complexity then also entails a higher effort - an increased degree of difficulty - for changes.