Welcome to the Design Patterns Repository! This repository serves as a comprehensive guide to object-oriented design patterns, with examples and explanations that will help developers understand, implement, and apply these patterns to real-world projects. By following this repository, you will learn how design patterns can improve code reusability, scalability, and maintainability while addressing common challenges in software engineering.
Design patterns are proven solutions to recurring software design problems. They provide templates for solving issues related to object creation, composition, and communication. Design patterns are categorized into three main types:
By using design patterns, developers can:
Purpose: Ensures that a class has only one instance and provides a global access point to it.
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Purpose: Extends Singleton by allowing multiple instances, identified by unique keys.
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Purpose: Defines an interface for creating objects but lets subclasses decide the type of object to instantiate.
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Purpose: Provides an interface for creating families of related or dependent objects without specifying their concrete classes.
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Purpose: Constructs complex objects step by step.
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Purpose: Creates new objects by copying existing ones.
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Purpose: Dynamically adds responsibilities to an object.
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Purpose: Converts one interface into another expected by clients.
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Purpose: Decouples abstraction from implementation.
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Purpose: Composes objects into tree structures to represent part-whole hierarchies.
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Purpose: Provides a surrogate or placeholder for another object.
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Purpose: Minimizes memory usage by sharing common data among objects.
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Purpose: Encapsulates algorithms and makes them interchangeable.
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Purpose: Defines a one-to-many dependency between objects.
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Purpose: Encapsulates requests as objects.
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Purpose: Allows an object to change its behavior when its state changes.
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Purpose: Passes requests along a chain of handlers.
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Purpose: Provides a way to access elements in a collection without exposing its underlying structure.
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Purpose: Reduces communication complexity by centralizing object interactions.
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Purpose: Captures an object’s state for later restoration.
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Purpose: Defines the skeleton of an algorithm, allowing subclasses to fill in the details.
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Purpose: Separates operations from the object structure.
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Purpose: Reduces tight coupling by providing dependencies from the outside.
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Purpose: Handles unexpected errors gracefully.
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This repository showcases design patterns in various contexts:
Use Maven for building and running the code:
mvn compile
mvn exec:java
mvn test
mvn package
mvn clean
Mastering design patterns is essential for crafting high-quality software. This repository serves as a guide to understanding and applying these patterns effectively in real-world projects.
Happy coding! 🚀