Adapter is a structural design pattern, which allows incompatible objects to collaborate.
The Adapter acts as a wrapper between two objects. It catches calls for one object and transforms them to format and interface recognizable by the second object.
Usage examples: The Adapter pattern is pretty common in C# 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.
Conceptual Example
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?