34 lines
831 B
Markdown
34 lines
831 B
Markdown
---
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title: MonoState
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category: Creational
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language: en
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tags:
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- Instantiation
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---
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## Also known as
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Borg
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## Intent
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Enforces a behaviour like sharing the same state amongst all instances.
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## Class diagram
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## Applicability
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Use the Monostate pattern when
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* The same state must be shared across all instances of a class.
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* Typically this pattern might be used everywhere a Singleton might be used. Singleton usage however is not transparent, Monostate usage is.
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* Monostate has one major advantage over singleton. The subclasses might decorate the shared state as they wish and hence can provide dynamically different behaviour than the base class.
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## Typical Use Case
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* The logging class
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* Managing a connection to a database
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* File manager
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## Real world examples
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Yet to see this.
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