In software engineering, SOLID is a mnemonic acronym for five design principles intended to make software designs more understandable, flexible, and maintainable. The principles are a subset of many principles promoted by American software engineer and instructor Robert C. Martin, first introduced in his 2000 paper Design Principles and Design Patterns.
The SOLID ideas are
The single-responsibility principle: “There should never be more than one reason for a class to change.” In other words, every class should have only one responsibility.
The open-closed principle: “Software entities … should be open for extension, but closed for modification.”
The Liskov substitution principle: “Functions that use pointers or references to base classes must be able to use objects of derived classes without knowing it.”
The interface segregation principle: “Many client-specific interfaces are better than one general-purpose interface.”
The dependency inversion principle: “Depend upon abstractions, not concretions.
you can find the sample code here
