Adapter pattern - Structural

• works as adapter between two incompatible interfaces 
• Convert the existing interfaces to a new interface to achieve compatibility and
• re-usability of the unrelated classes in one application 
• Convert the interface of a class into another interface clients expect 
• Also known as Wrapper pattern 

Where to use ?

• Make unrelated classes work together
• Multiple compatibility
• Achieve the goal by inheritance or by composition.

Implementation example

• Interface Connectivity declares basic method to provide connectivity in mobiles
• Class Bluetooth implements Connectivity
• Client uses Bluetooth class

     In order to support NFC also, create an adapter :

• Create another class ConnectivityAdapter implementing Connectivity interface
• Class ConnectivityAdapter will use existing Bluetooth class and another classes providing NFC functions
• Client can now use ConnectivityAdapter instead of Bluetooth