The Dependency Inversion Principle (DIP) is the fifth and final principle in the SOLID acronym, introduced by Robert C. Martin (“Uncle Bob”). DIP states that: High-level modules should not depend on low-level modules. Both should depend on abstractions. In other words, classes that manage significant business logic (high-level) shouldn’t directly rely on concrete classes (low-level). […]
The Interface Segregation Principle (ISP) is the fourth pillar in the SOLID acronym, introduced by Robert C. Martin. It states that “Clients should not be forced to depend upon interfaces that they do not use.” In simpler terms, it’s better to create multiple, smaller, more specific interfaces than a single large interface that tries to
The Liskov Substitution Principle (LSP) is the third letter in the popular SOLID acronym. Introduced by Barbara Liskov, it states that subtypes must be replaceable for their base types without altering the correctness (or expected behavior) of the program. In simpler terms, any time you use a parent class reference in your code, you should
The Open/Closed Principle (OCP) is the second letter in the SOLID acronym, proposed by Bertrand Meyer and later championed by Robert C. Martin (“Uncle Bob”). OCP states that software entities (classes, modules, functions, etc.) should be open for extension, but closed for modification. In simpler terms, you should be able to add new features or
The Single Responsibility Principle (SRP), the first of the SOLID design principles, states that each class should have one reason to change—in other words, one job. Below is a more detailed class diagram that illustrates how you might separate different responsibilities into their own classes. Detailed Class Diagram Order Class Single Responsibility: The Order class