Java Generics: extends, super and wildcards explained | OneWebSQL

Extend
You often want to restrict the set of types that can be used in instantiation. 
class ParkingGarage<X extends Vehicle & MotorVehicle & PassengerVehicle>
You can specify at most one class in the bound (obviously, as you can only inherit from one class in Java) and as many interfaces as you want.

You can't use super in class declaration

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