In object-oriented programming, the dependency inversion principle refers to a specific form of decoupling where conventional dependency relationships established from high-level, policy-setting modules to low-level, dependency modules are inverted (i.e. reversed) for the purpose of rendering high-level modules independent of the low-level module implementation details. The principle states:
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- A. High-level modules should not depend on low-level modules. Both should depend on abstractions.
- B. Abstractions should not depend upon details. Details should depend upon abstractions.
The principle inverts the way some people may think about object-oriented design, as both high- and low-level objects depend on the same abstraction.
Read more about Dependency Inversion Principle: Description, History
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