SOLID software design principles


SOLID

Single-responsibility principle

A class should only have a single responsibility, that is, only changes to one part of the software’s specification should be able to affect the specification of the class.

Open–closed principle

“Software entities … should be open for extension, but closed for modification.”

Liskov substitution principle

“Objects in a program should be replaceable with instances of their subtypes without altering the correctness of that program.” See also design by contract.

Interface segregation principle

“Many client-specific interfaces are better than one general-purpose interface.”

Dependency inversion principle

“One should “depend upon abstractions, [not] concretions.”

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