Observer Pattern
The Observer Pattern is a behavioral desing pattern in object-oriented programming. It defiens a one-to-many dependency between objects so that when one object (the subject) changes its state, all its dependents (observers) are notified and updated automatically. In other words, the observer pattern allows one object to inform a list of other objects about changes without knowing who or what those objects are.
Explantion with Real World Example
Think of a real-world scenario of a news agency and its subscribers:
- Subject (News Ajency): The news agency is the subject. It generates news and broadcasts it.
- Observer (Subscribers): Subscribers are the observers. They subscribe to the news agency to receive updates.
- Update Mechanism: When the news agency publishes a new article or breaking news, all subscribers receive the updates without the news agency knowing who they are or how many there are.
This real-wrold analogy demonstrates how the observer patten works. The news agenchy (subject) informs its subscribers (observers) about changes without needing to be aware of the specific subscribers.
The Observer Pattern is used in various scenarios where a one-to-many relationship exists between objects, and one subject needs to notify multiple others about changes.
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