The Open Closed Principle

In this post, I continue to share what I have learned about the SOLID principles in the book “Clean Architecture A Craftsman’s Guide to Software Structure and Design”. As a recap, six principles make up the SOLID acronym:

• The Single Responsibility Principle.
• The Open Closed Principle.
• The Liskov Substitution Principle.
• The Interface Segregation Principle.
• The Dependency Inversion Principle.

In the previous post, I wrote about the Single Responsibility Principle. In this post, I write about the Open Closed Principle.

The Single Responsibility Principle

Recently, I read the book “Clean Architecture” by Robert C. Martin. Overall, this is a great book with a wealth of information on software design principles to guide developers to build scalable, maintainable and flexible applications. A core part of the book discusses about six design principles which together make up the acronym SOLID.

Repository pattern

The repository pattern is a common pattern for accessing data from a database and converting the data into an entity. The repository pattern is property the one I have used the most. But just recently, I started reading more on the different design patterns and realized a few things I did not know or misunderstood about the pattern.

Multi-layer / Multi-tier architectural pattern

In the past, I had been working on applications that were multi-layered / multi-tier applications. However, I had not recognized the terminologies as well as the subtle differences between multi-layered and multi-tier architectures and some of the pitfalls one may want to watch out for when implementing the pattern.