IoC and DI - Purpose and Benefits.

IoC (Inversion of Control):

A design principle where the control of object creation and lifecycle is transferred from the application code to a container or framework (Spring IoC Container).

DI (Dependency Injection):

A pattern used to implement IoC. Instead of an object creating its dependencies, the dependencies are "injected" into it (via Constructor, Setter, or Field).

Benefits:

1. Decoupling: Classes are not tightly coupled to specific implementations.
2. Testability: Dependencies can be easily mocked for unit testing.
3. Maintainability: Changes in one part of the system have minimal impact elsewhere.