Implementierung von Inversion of Control durch Konstruktor-Injektion

@Service
public class OrderService {
 
    private final PaymentGateway paymentGateway;
 
    public OrderService(PaymentGateway paymentGateway) {
        this.paymentGateway = paymentGateway;
    }
 
    public boolean processOrder(double amount) {
        return this.paymentGateway.charge(amount);
    }
}