Command Design Pattern

Encapsulate a request as an object, thereby allowing for the parameterization of clients with different requests, and the queuing or logging of requests. It also allows for the support of undo operations.

Advantages

• It decouples the classes that invoke the operation from the object that knows how to execute the operation
• Allows you to create a sequence of commands by providing a queue system
• Extensions to add a new command is easy and can be done without changing the existing code
• You can also define a rollback system with the Command pattern

Disadvantages

• There are a high number of classes and objects working together to achieve a goal. Application developers need to be careful developing these classes correctly
• Using command design pattern may requires more effort on implementation, since each command requires a concrete command class