Design Patterns with Code Examples
Design patterns are reusable solutions to common problems that occur in software design. Think of them as tried-and-tested templates or blueprints that help developers solve similar problems consistently and efficiently.
Imagine you want to build a house, and you notice that many houses have a similar layout or features. Instead of designing each house from scratch, you can use a predefined blueprint that outlines the structure, room arrangements, and other details. Similarly, design patterns provide a set of guidelines and best practices for solving specific problems in software development.
Design patterns come in different types and serve various purposes. Some patterns help with organizing code, some improve communication between different components of a system, and others enhance flexibility and maintainability. They encapsulate proven solutions, making it easier for developers to understand, implement, and modify software systems.
By using design patterns, developers can save time and effort, promote code reusability, and create more robust and scalable applications. They are like tools in a developer's toolbox, helping them tackle common challenges effectively while producing high-quality software.
Design patterns can be divided into three main categories:
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Creational Patterns
- Factory Method
- Abstract Factory
- Singleton
- Builder
- Prototype
- Object Pool
- Lazy Initialization
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Structural Patterns
- Adapter
- Bridge
- Composite
- Decorator
- Facade
- Flyweight
- Proxy
- Active Record
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Behavioral Patterns
- Chain of Responsibility
- Command
- Interpreter
- Iterator
- Mediator
- Memento
- Observer
- State
- Strategy
- Template Method
- Visitor
- Null Object