Design patterns
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Design patterns provide reusable solutions to common programming problems. They optimize applications for maintenance, scalability, and reusability. Common patterns include Singleton, MVC, Factory Method, and Observer. Singleton ensures only one instance of a resource. MVC separates business logic from presentation logic. Factory Method creates object instances without specifying classes. Observer allows one object to watch changes in another. Design patterns reduce development time by avoiding reinventing solutions.
Design patterns
- 2. What is a Design Pattern?It is a known solution to commonly occurring problems or scenarios in software applications.A kind of a template or structure on which one can code the application.
- 3. Why use a Design Pattern?Reduces development time, as known solutions are used instead of reinventing the wheel.Optimizes the application in terms of:MaintenanceScalability Re-usability
- 4. Different Design PatternsFew Common design patterns:SingletonMVCFactory MethodObserver
- 5. SingletonUsed in applications when only a single instance of a resource is required.(Ex: Database connection)
- 6. MVCMost commonly used design pattern.Separates the business logic and presentation logic.Uses Controller for interaction between Model and View.
- 7. Factory MethodObject oriented creational pattern.Method is used to create and initiate objects for classes.An interface is defined for creating an object, but the subclasses decide which class to instantiate.
- 8. Observer PatternAllows one object (the observer) to watch another (the subject).It decouples the observer from the subject.When the subject generates an event, it is passed to each of its observers.
- 10. Choosing a Design PatternAnalyze the requirements.Understand the nature of the problemDetermine how a particular design pattern solves that problem.