Introduction To Design Patterns

In Software Development we often found problems which are commonly encountered, Design Patterns are well established solutions to those recurring problems.They provide a proven approach to solving a specific software design problem, which has been evolved over the years by trial and error by software engineers. Design Patterns are like blueprints , templates that you can customise according to the requirement to solve a design problem

Are they Similar To Algorithms?

Design Patterns are often confused with the Algorithms. While algorithm is a specific set of instructions to solve a specific problem whereas Design Pattern is a high level description of a design solution. It is more like a way of implementations. While algorithm is a reusable piece of code to a specific problem but Design Pattern can not be used as it is and needs to be customised to fit into your design problem.

Why use Design Patterns ?

It is considered a good practice to use Design Patterns in Software Development as it helps in the long run. By using the design patterns you can make your application more scalable, reusable and maintainable. It leads to a faster development process by providing tested, proven development paradigms that have evolved all the years.

Effective software design requires considering issues that may not become visible until later in the implementation. Newly implemented code may often have hidden issues that take time to be detected, issues that sometimes can cause major problems down the road and may lead to complete overhaul of the application resulting in wastage of time and effort.Reusing design patterns helps to prevent such design issues, and it also improves code readability for coders and architects who are familiar with the patterns.

1. Reusability: Design Patterns can be reused in multiple projects, saving development time and effort.
2. Standardization: They provide a common language and understanding for developers, leading to consistent designs and coding practices.
3. Scalability: They can help make software more scalable and adaptable to changing requirements.
4. Maintainability: They make software easier to maintain and modify over time, reducing the risk of introducing bugs and increasing the lifespan of the software.
5. Code quality: They promote good coding practices, resulting in better code quality and more robust software.
6. Collaboration: Design Patterns provide a shared vocabulary and understanding among team members, improving communication and collaboration.
7. Learning: Using design patterns can help developers learn new techniques and best practices, leading to personal and professional growth.

Classification of Design Patterns-

Design patterns can be categorized into three main groups: creational patterns, structural patterns, and behavioral patterns.

1. Creational patterns: Creational patterns focus on object creation .They are used to create objects and classes in a way that is flexible, efficient, and more maintainable. There are five design patterns in this category:

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

2. Structural patterns: Structural patterns focus on object composition and are used to create relationships between objects and classes. They help in designing the architecture of the application. There are seven design patterns in this category:

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

3. Behavioral patterns: Behavioral patterns focus on object interaction and communication .They help in defining how objects interact with each other and the system. There are eleven design patterns in this category:

• Chain of Responsibility Pattern
• Command Pattern
• Interpreter Pattern
• Iterator Pattern
• Mediator Pattern
• Memento Pattern
• Observer Pattern
• State Pattern
• Strategy Pattern
• Template Method Pattern
• Visitor Pattern

These categories are not mutually exclusive, and some of them may fall under more than one category.

Conclusion

Overall, design patterns can help developers create better software that is easier to develop, maintain, and extend. In Conclusion, design patterns provide a common vocabulary for developers to use when discussing software design. They help to reduce complexity, improve maintainability, and provide a standard approach to solving problems. By understanding and using these, developers can create better software that is easier to understand, maintain, and scale.

However it should be kept in mind that as one size does not fits all the design patterns are not a silver bullet and should be used judiciously according to requirement.