Singleton

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Singleton
Contributors Erich Gamma, Richard Helm, Ralph Johnson, John Vlissides
Last modification March 29, 2017
Source Gamma, Helm, Johnson & Vlissides (1995)[1], Singleton Pattern (2016)[2]
Pattern formats OPR Alexandrian
Usability
Learning domain
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If a system only needs one instance of a class, and that instance needs to be accessible in many different parts of a system, you control both instantiation and access by making that class a singleton.[1][2]


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  1. 1.0 1.1 Gamma, E., Helm, R., Johnson, R. & Vlissides, J. (1995). Design Patterns: elements of reusable object-oriented software. Addison-Wesley: Boston, MA. ISBN 0-201-63361-2.
  2. 2.0 2.1 Singleton Pattern. (2016). Retrieved October 4, 2016 from http://c2.com/cgi/wiki?SingletonPattern.