| layout | pattern | |||
|---|---|---|---|---|
| title | Singleton | |||
| folder | singleton | |||
| permalink | /patterns/singleton/ | |||
| pumlid | HSV14SCm20J0Lk82BFxf1ikCh0n26ZZizfDVVhjRjwfvIhg-Bc35cyZvAQtZoYD3l4w364gTWxhcms2d3z-ydnAzsRuO4BUWmV43HRUcWcaagF-Lz55M3lq2 | |||
| categories | Creational | |||
| tags |
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Ensure a class only has one instance, and provide a global point of access to it.
Use the Singleton pattern when
- there must be exactly one instance of a class, and it must be accessible to clients from a well-known access point
- when the sole instance should be extensible by subclassing, and clients should be able to use an extended instance without modifying their code
- the logging class
- managing a connection to a database
- file manager