Six Programming Principles You need to follow. (In the Company)

SOLID Principles

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

SRP

• Cohesion

• • Relation of responsibilities
• • Focused on single task

• Coupling

• • Dependency on other modules
• • Relationship between modules

• Ideal: low coupling + strong cohesion

OCP

• Open to extension
• • New behavior can be added later
• Closed to modification
• • Changes to source or binary code are not required
• Change behavior without changing the code?!
• • Yes,this is possible, e.g. by inheritance or by parameterization
• • Rely on abstractions, not on implementations
• • Do not limit the variety of implementations

LSP

• Comes from MIT professor
• Substitutability – child classes must not
• • Remove parent class behavior
• • Violate parent class intent
• Instead of dad fight

ISP

• Segregate interfaces
• • Prefer small, cohesive interfaces
• • Divide "fat" interfaces into smaller ones
• Having "fat" interfaces leads to:
• • Classes having methods they do not need
• • Increased coupling
• • Reduced flexibility / maintainability

DIP