Inversion of control
On This Lesson 4 topics
This lesson is planned. The outline below lists the topics it will cover. The full lesson has not been published yet.
In this lesson
explain IoC and dependency injection without Spring.
Planned topics
- Inversion of control (IoC): someone else creates and connects your objects; you stop doing it.
- Dependency injection (DI) is the common form: dependencies are handed in from outside.
- The class declares what it needs; it does not decide which implementation.
- Depend on an interface (
PaymentProvider), not a concrete class.
Draft outline details
Demonstration
class OrderService {
private final PaymentProvider payment;
OrderService(PaymentProvider payment) { this.payment = payment; }
}
var service = new OrderService(new StripePayment()); // main() acts as the "container"Check your understanding
Who decides which implementation is used now?
Show answer
The caller or container, not the service.
Practice
Apply this lesson with the module's lab, exercises and quiz.
Marking a lesson complete is optional and you can undo it any time. Your progress stays in this browser.