Measuring Object-Orient Software Products

ion. The essential characteristics of an object that distinguish it from all other kinds of objects, and thus provide, from the viewer's perspective, crisply-defined conceptual boundaries; the process of focusing upon the essential characteristics of an object. Aggregate object (aggregation). An object composed of two or more other objects. An object that is part of two or more other objects. Attribute. A variable or parameter that is encapsulated into an object. Class. A set of objects that share a common data structure (called attributes) and a common behavior manifested by a set of methods; the set serves as a template from which objects can be created.1 Cohesion. The degree to which the methods within a class are related to one another.2 Collaborating classes. If a class sends a message to another class, the classes are said to be collaborating. Coupling. Class X is coupled to class Y if and only if X sends a message to Y. 1 There are other interpretations of class 2 Here, cohesion is limited to cohesion within a class.