Static Class Structure

• Client
  • Refers to (depends on) the Target interface.
• Target
  • Defines an interface the Client class requires.
• Adapter
  • Implements the Target interface in terms of Adaptee.
• Adaptee
  • Defines a class that gets adapted.

Dynamic Object Collaboration

• In this sample scenario, a Client object works with a Target object directly and through an adapter (of type Target) with an Adaptee object.
• The interaction starts with the Client object that calls operation() on a Target object, which performs the request and returns to the Client.
• Thereafter, the Client calls operation() on an adapter object (of type Target).
• adapter calls specificOperation() on an Adaptee object, which performs the request and returns to the adapter, which in turn returns to the Client.
• adapter can do work of its own before and/or after forwarding a request to Adaptee.
• See also Sample Code.