出典:Wiktionary
出典:『Wiktionary』 (2025/02/20 03:44 UTC 版)
singleton pattern (plural singleton patterns)
出典:Wikipedia
出典:『Wikipedia』 (2011/07/25 11:29 UTC 版)
In software engineering, the singleton pattern is a design pattern used to implement the mathematical concept of a singleton, by restricting the instantiation of a class to one object. This is useful when exactly one object is needed to coordinate actions across the system. The concept is sometimes generalized to systems that operate more efficiently when only one object exists, or that restrict the instantiation to a certain number of objects (say, five). Some consider it an anti-pattern, judging that it is overused, introduces unnecessary limitations in situations where a sole instance of a class is not actually required, and introduces global state into an application.