Design PrinciplesEach Programmer should know

These are very simple abstract but common practical principles which should be kept in mind by the real developers.

KISS

Keep it simple and stupid, keep it short and straightforward.

SoC

Separation of concerns. Separate into individual concerns, or modulars.

High cohesion

Cohesion refers to the degree to which the elements of a module belong together.

DRY

Don’t repeat yourself.

SRP

Single responsibility principle, ‘S’ of ‘SOLID’. Every time do one thing only.

ISP

Interface segregation principle, ‘I’ of ‘SOLID’. If implement Class do not need all methods, it means the interface should be separated to 2 or more ones.

CQS

Command-query separation. Every method should either be a command to set state or a query returns something.

REP

Release reuse equivalence principle, package principles. The granule of reuse is the granule of release.

CCP

Common closure principle, package principles. Classes that change together are packaged together.

CRP

Common reuse principle, package principles. Classes that are used together are packaged together.

Low coupling

Coupling or dependency is the degree to which each program module relies on each one of the other modules.

OCP

Open-closed principle, ‘O’ of ‘SOLID’. Open for extension, closed for modification.

LSP

[Liskov] substitution principle, ‘L’ of ‘SOLID’. Base types can be surely substituted by their subtypes.

DIP

Dependency inversion principle, ‘D’ of ‘SOLID’. High-level modules should not depend on low-level modules; abstractions should not depend on details.

LoD

Law of [Demeter]. Know as least as you can.

IoC

Inversion of Control. Don’t call us, we’ll call you. Instead of calling reusable codes such as libraries from custom codes in traditional way, let reusable codes like framework to call the custom codes.

IoI

Interface over implementation.

CoI

Composition over inheritance.

CoC

Convention over Configuration.

ADP

Acyclic dependencies principle, package principles. No cycle dependency exists.

Design smells