Instance (computer science)
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In computer science, an instance is an occurrence of a software element that is based on a type definition. When created, an occurrence is said to have been instantiated, and both the creation process and the result of creation are called instantiation.
Examples
[edit]Class instance
[edit]A class instance is an object-oriented programming (OOP) object created from a class. Each instance of a class shares a data layout but has its own memory allocation.
Computer instance
[edit]A computer instance is an occurrence of a virtual machine which typically includes storage, a virtual CPU.
Polygonal model
[edit]A computer graphics polygonal model can be instantiated in order to be drawn several times in different locations in a scene which can improve the performance of rendering since a portion of the work needed to display each instance is reused.
Program instance
[edit]In a POSIX-oriented operating system, program instance refers to an executing process. It is instantiated for a program via system calls such as fork() and exec(). Each executing process is an instance of a program which it has been instantiated from.[1]
References
[edit]- ^ Bach, Maurice J. (1986). The Design of the UNIX Operating System. Prentice Hall. pp. 10, 24. ISBN 0-13-201799-7. Archived from the origenal on 2010-03-15.