Maintainability

The maintainability ( English maintainability , supportability or serviceability ) of software is a criterion in the development of software and shows the energy and success with which changes can be made in a system context of applications.

Maintainability is all the more important

• the longer the planned period of use of the software
• the lower the availability of experts for the subject

Important criteria for the maintainability of software are:

• the documentation , in particular, the exact specification of interfaces (interfaces)
• a modular , highly structured structure (breakdown into elementary, individually testable units)
• the absence of jump instructions ("GOTO" commands)
• the local intelligibility of instructions
• avoiding global variables
• the parameterizability of functions and methods
• Tests built into the program of the assumptions that the programmer has about program states ( assertions )
• the largest possible range of automatically executable tests for the system
• the use of generally known and recognized design patterns

Maintainability is one of the criteria that determine the further development of programming languages .

To determine the maintainability is based on-line metrics, McCabe and Halstead metrics of maintainability index (Engl. Maintainability Index ) is calculated.

See also

• Software maintenance
• Evolvability (software)
• Support (service)

literature

• Ch. Bommer, M. Spindler, V. Barr: Software maintenance - basics, management and maintenance techniques , dpunkt.verlag, Heidelberg 2008, ISBN 3-89864-482-0

Web links

• Tools for determining maintainability: Testwell CMT ++ and CMTJava
• Calculation of maintainability based on a sample project (PDF file; 737 kB)
• Introduction to maintainability, J. Meiert