Usage examples: The Adapter pattern is pretty common in Ruby code. It’s very often used in systems based on some legacy code. In such cases, Adapters make legacy code work with modern classes.
Identification: Adapter is recognizable by a constructor which takes an instance of a different abstract/interface type. When the adapter receives a call to any of its methods, it translates parameters to the appropriate format and then directs the call to one or several methods of the wrapped object.
This example illustrates the structure of the Adapter design pattern. It focuses on answering these questions:
What classes does it consist of?
What roles do these classes play?
In what way the elements of the pattern are related?