Common Structural Patterns

There are a great many popular design patterns. The list below includes a few of the most fundamental and popular patterns for structuring classes.

Front-Ending Class Patterns

• Adapter
  A wrapper to translate an available object in to the form expected by a client.
• Facade
  A simple front-end class that encapsulates the details of how to implement desired functionality out of (more complex) existing functionality.
• Proxy
  A local object whose purpose is to act as an interface to some other object.
• Strategy
  A class that supports run-time selectable, plug-in implementations.

Instantiation Class Patterns

• Abstract Factory
  A general approach to instatiating elements of a class with multiple sub-classes.
• Singleton
  A class that there will (guaranteed) only ever be one element of.
• Object Pool
  A means of reducing the cost of instantiation and destruction for popular, short-lived, objects.