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DESIGN PATTERN: Command

· pattern

The ____ Pattern is a design pattern that encapsulates requests as objects, allowing you to parameterize and control their execution. It promotes flexibility and supports features like undo/redo and command queuing.

* Interpreter

* Command

* Observer

* Pipeline

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Answer: Command

The Command Pattern is a behavioral design pattern in software development that encapsulates a request or action as an object. It allows you to parameterize clients with requests, delay execution, queue requests, or support undoable operations.

Key components of the Command Pattern:

Command: The Command is an interface or abstract class that declares the execution method (e.g., execute()) that concrete commands must implement. It represents a specific action or request.

Concrete Command: Concrete Command classes implement the Command interface and encapsulate the details of a specific request or action. They hold the receiver object and specify how the request should be executed.

Receiver: The Receiver is the object that performs the actual work associated with a command. It is invoked by the Concrete Command when the command is executed.

Invoker: The Invoker is responsible for invoking and managing commands. It maintains a collection of commands and can queue, schedule, or log them. It invokes the command's execute() method when needed.

Client: The Client is responsible for creating and configuring commands and associating them with specific receivers. It sets up the relationships between commands, receivers, and invokers.

The Command Pattern decouples the sender (Client) from the receiver (Receiver) by encapsulating requests as objects. This promotes flexibility, extensibility, and the ability to support various request types.

It's commonly used in scenarios like menu systems, macro recording, and undo/redo functionality.