Design Patterns

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Design patterns are typical solutions to commonly occurring problems in software design. They are like pre-made blueprints that you can customize to solve a recurring design problem in your code.

You can’t just find a pattern and copy it into your program, the way you can with off-the-shelf functions or libraries. The pattern is not a specific piece of code, but a general concept for solving a particular problem. You can follow the pattern details and implement a solution that suits the realities of your own program.

Classification of patterns

Creational Patterns

These patterns provide various object creation mechanisms, which increase flexibility and reuse of existing code.

• Factory Method
• Builder
• Singleton
• Abstract Factory
• Prototype

Structural Patterns

These patterns explain how to assemble objects and classes into larger structures while keeping these structures flexible and efficient.

• Adapter
• Bridge
• Composite
• Decorator
• Facade
• Flyweight
• Proxy

Behavioral Patterns

These patterns are concerned with algorithms and the assignment of responsibilities between objects.

• Chain of resposibility
• Command
• Iterator
• Mediator
• Memento
• Observer
• State
• Strategy
• Template Method
• Visitor

Commits in this repo

Each commit will represent another design pattern.

Idea is to commit once a day everyday through 22 days.

Each commit will include:

• Code example in src/
• doc.md - about current design pattern
• img/ - image files for doc.md
• this very file (design_patterns.md)

commit names

Each commit concerns one design pattern so:

<name.toUpper()> (<group>)

For example:

BUILDER (Creational Pattern)

sequence

Sequence is based on popularity and my desire to learn concrete design pattern:

• FACTORY METHOD (Creational Pattern)
• DECORATOR (Structural Pattern)
• OBSERVER (Behavioral Pattern)
• SINGLETON (Creational Pattern)
• STATE (Behavioral Pattern)
• ADAPTER (Structural Pattern)
• STRATEGY (Behavioral Pattern)
• BUILDER (Creational Pattern)
• COMMAND (Behavioral Pattern)
• CHAIN OF RESPONSIBILITY (Behavioral Pattern)
• PROTOTYPE (Creational Pattern)
• TEMPLATE METHOD (Behavioral Pattern)
• PROXY (Structural Pattern)
• ITERATOR (Behavioral Pattern)
• BRIDGE (Structural Pattern)
• ABSTRACT FACTORY (Creational Pattern)
• MEDIATOR (Behavioral Pattern)
• FACADE (Structural Pattern)
• MEMENTO (Behavioral Pattern)
• COMPOSITE (Structural Pattern)
• VISITOR (Behavioral Pattern)
• FLYWEIGHT (Structural Pattern)