command

Command pattern

The Command pattern should be used when:

The purpose of the pattern is to decouple the Receiver from the Invoker.

• Receiver is the object that "knows" how to perform the action. It hold the business logic. of the application.
• Invoker is the actual executor of the command. I doesn't know nothing about the Receiver.
• The Command takes the Receiver object: Command cmd = new SomeCommand(Receiver r).
• The Client has responsibilities to instantiate the Command object and to inject it to the Invoker.