SOLID is a set of principles for writing software that is easy to understand, maintain, and extend. These principles are designed to help developers create software that is modular, scalable, and robust.
Here is a brief explanation of each of the SOLID principles:
- Single Responsibility Principle (SRP): This principle states that a class should have only one reason to change. In other words, a class should have a single responsibility and should only be responsible for a single part of the functionality. This helps to keep the code simple and easy to understand.
For example, if you have a car, the car should only be responsible for driving. It shouldn't also be responsible for making your breakfast or doing your homework. This helps to keep things simple and easy to understand.
- Open/Closed Principle (OCP): This principle states that a class should be open for extension but closed for modification. In other words, you should be able to add new functionality to a class without changing its existing code. This helps to protect the class from breaking when you make changes to it.
For example, if you have a toy box, you should be able to add new toys to the box without changing the box itself. This helps to keep the toy box from breaking when you add new toys.
- Liskov Substitution Principle (LSP): This principle states that if a class is a subtype of another class, it should be able to be used in the same way as the parent class without causing any problems. This helps to ensure that the code is flexible and can be easily extended.
For example, if you have a toy car and a real car, the toy car should be able to be used in the same way as the real car (for example, to drive around the room) without causing any problems. This helps to make sure that things are flexible and can be used in different ways.
- Interface Segregation Principle (ISP): This principle states that a class should not be forced to implement interfaces that it does not use. In other words, a class should only have to implement the interfaces that it needs in order to do its job. This helps to keep the code simple and focused.
For example, if you have a toy robot, the robot should only have to do things that robots do (such as moving around and making noises), and not things that robots don't do (such as making breakfast or doing homework). This helps to keep things simple and focused.
- Dependency Inversion Principle (DIP): This principle states that a class should depend on abstractions, not on concrete implementations. In other words, a class should not depend on a specific implementation of another class, but rather on an interface that defines how the two classes should interact. This helps to make the code more flexible and easier to change.
For example, if you have a toy car and a toy truck, the toy car should depend on a general "vehicle" interface that both the car and the truck implement, rather than on the specific implementations of the car and the truck. This helps to make things more flexible and easier to change.
I hope these examples help to clarify the SOLID principles! Let me know if you have any questions or need further assistance.
You should also check KISS, DRY, YAGNI