Command Pattern
The Command Pattern is a behaviroal desing pattern in object-oriented programming that encapsulats a request as an object, thereby allowing for parameterization of clients with queues, requests, and operations. It turns a request into a standalone object with its own class, parameters, and methods to invoke the request. This pattern decouples the sender and receiver of a request. allowing for the sender to issue requests without needing to know the specific operations or the receiver’s class.
Explanation with Real World Example
Let’s consider a real-world scenario involving a remote control for a television:
- Command: In this context, a command is a representation of a specific operation, like turning the TV on, changing the channel, or adjusting the volume. Each command is encapsulated as an object with a defined method.
- Invoker (Remote Control): The remote control is the invoker. It holds a list of commands and can execute them without needing to know the details of the TV’s internal workings.
- Receiver (TV): The television is the receiver. It understandsthe individual commands, such as how to turn on or change channels. The commands act as intermediaries to invoke the appropriate methods on the receiver.
In this example, the Command Pattern allows the remote control (invoker) to issue various commands to the TV (receiver) without requiring a deep understanding of the TV’s internal operations. The remote control interacts with commands that encapsualte specific actions, providing a more flexible and decoupled way to control the TV.
The Command Pattern is used in various scenarios where you want to encapsulate requests as objects and decouple the sender and receiver of the requests.
Design Patterns in Object-Oriented Programming (OOP)
Software Development is like putting together a puzzle. Object-oriented programming (OOP) is a popular way to build complex software, but it can be tricky when you face the same design problems repeatedly. That’s where design patterns come in.
Design patterns are like well-known recipes for common problems in software development. They’re not step-by-step instructions, but more like guidelines to help you solve these problems in a flexible and efficient way. These patterns gather the wisdom of the software development community, making it easier for developers to work together and create software that’s easy to maintain, adapt, and reuse.
Important Topics for the Design patterns in object-oriented programming
- Singleton Pattern
- Factory Method Pattern
- Abstract Factory Method Pattern
- Builder Pattern
- Adapter Pattern
- Proxy Pattern
- Decorator Pattern
- Composite Pattern
- Observer Pattern
- Strategy Pattern
- Command Pattern
- State Pattern
- Template Method Pattern
- Visitor Pattern
- Memento Pattern
- Conclusion