Encapsulation (computer programming): Difference between revisions

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In ana programming language <!-- [[object-oriented programming language]]--> <!-- and related fields, like [[OODMBS]],--> '''encapsulation''' is used to refer to one of two related but distinct notions, and sometimes to the combination<ref>Michael Lee Scott, ''Programming language pragmatics'', Edition 2, Morgan Kaufmann, 2006, ISBN 0126339511, p. 481: "Encapsulation mechanisms enable the programmer to group data and the subroutines that operate on them together in one place, and to hide irrelevant details from the users of an abstraction."</ref><ref name=Dale>Nell B. Dale, Chip Weems, ''Programming and problem solving with Java'', Edition 2, Jones & Bartlett Publishers, 2007, ISBN 0763734020, p. 396</ref> thereof:

* A language mechanism for restricting access to some of the [[object (computer science)|object]]'s components.<ref>[[John C. Mitchell]], ''Concepts in programming languages'', Cambridge University Press, 2003, ISBN 0521780985, p.522</ref><ref name=Pierce>{{cite book|last=Pierce|first=Benjamin|authorlink=Benjamin C. Pierce|title=[[Types and Programming Languages]]|publisher=MIT Press|year=2002|id=ISBN 0-262-16209-1}} p. 266</ref>

* A language construct that facilitates the bundling of data with the methods operating on that data.<ref>Wm. Paul Rogers, [http://www.javaworld.com/javaworld/jw-05-2001/jw-0518-encapsulation.html?page=9 ''Encapsulation is not information hiding''], JavaWorld.com, 05/18/01</ref><ref>Thomas M. Connolly, Carolyn E. Begg, ''Database systems: a practical approach to design, implementation, and management'', Edition 4, Pearson Education, 2005, ISBN 0321210255, Chapter 25, "Introduction to Object DMBS", section "Object-oriented concepts", p. 814</ref>

ProgrammingSome programming language researchers and academics generally use the first meaning alone or in combination with the second as a [[Object oriented programming#features|distinguishing feature of object oriented programming]], while other programming languages which provide [[Closure_(computer_programming)|lexical closures]] view encapsulation as a feature of the language orthogonal to object orientation.

The second definition is motivated by the fact that in many OOP languages hiding of components is not automatic or can be overridden; thus [[information hiding]] is defined as a separate notion by those who prefer the second definition.<!-- this is based on all the refs given above, so no inline cite here-->

== As information hiding mechanism ==