What is Dependency Injection? Explain with an example.

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Accepted Answer

Dependency injection is a design pattern that allows a class to receive its dependencies from an external source rather than creating them itself.

Inversion of Control: Dependency injection promotes loose coupling by allowing the control of dependencies to be inverted, meaning the framework or container manages them.
Constructor Injection: Dependencies are provided through a class constructor. For example, a `Car` class might receive an `Engine` instance via its constructor.
Setter Injection: Dependencies can also be set through public setters after the object is constructed. For instance, a `Database` class can have its connection set later.
Interface Injection: A dependency provides an injector method that will inject the dependency into any client that passes itself to the injector.
Benefits: Dependency injection enhances testability, maintainability, and flexibility of code by decoupling the creation of objects from their usage.

Accepted Answer

Dependency injection is a programming technique that makes a class independent of its dependencies

Accepted Answer

Dependency Injection (DI) is a programming technique that makes a class independent of its dependencies. Creating objects directly within the class is inflexible because it commits the class to particular objects and makes it impossible to change the instantiation later independently from the class.

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What is Dependency Injection? Explain with an example.

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