Technical matrices for Object-oriented system

Technical matrices for Object-oriented system

• Technical metrics provide a basis from which analysis, design, and testing can be conducted more objectively and assessed more quantitatively.

The primary objectives for object-oriented metrics are:

·  To better understand the quality of the product

·  To assess the effectiveness of the process

·  To improve the quality of work performed at a project level

• There are five characteristics that lead to specialized metrics: localization, encapsulation, information hiding, inheritance, and object abstraction techniques.

•      Localization

• It is a characteristic of software that indicates the manner in which information is concentrated within a program. OO software metrics have focused on the internal structure or complexity of functions or the manner in which functions connect to one another. Localization is based on objects. Therefore, metrics should apply to the class(object) as complete entity. In addition the relationship between operations(functions) and classes collaborate must be capable of accommodation one-to-many and many-to-one relationships.

•      Encapsulation

• Encapsulation influences metrics by changing the focus of measurement from a single module to a package of data(attributes) and processing modules(operations).

• Information hiding

• Information hiding suppresses(or hides) the operational details of a program component. Only the information necessary to access the component is provided to those other components that wish to access it. Metrics that provide an indication of the degree to which hiding has been achieved should provide an indication of the quality of the OO design.

•  Inheritance

• Inheritance is a mechanism that enables the responsibilities of one object to be propagated to other objects. Many OO metrics focus on it. Examples include number of children, number of parents, and class hierarchy nesting level.

•  Abstraction

• Abstraction is a mechanism that enables the designer to focus on the essential details of a program component (either data or process) with little concern for lower-level details. OO metrics represent abstractions in terms of measures of a class (e.g. number of instances per class per applications).