How to enforce subclasses to implement a method which accepts a certain type

Question

I want to simulate Smart Devices world. My plan was to create a hierarchy like this.

Smart Device as my main interface. Phone and Watch as classes which implement Smart Device. and Samsung and Apple as classes which extend Phone.

and finally I have two classes named ios and android which extend a superclass named Os.

I want to have the ability to enforce apple and samsung to install their own respective Os while I enforce the installation of Os on every Device(such as watch) which implements SmartDevice.

Therefore I created a method called istallOs(Os test) in my interface but the problem is I can not implement that method in phone level because I don't know if it is samsung or apple.

I am guessing my Hierarchy is not suitable for this problem and I should move installOs to a lower level.

What is the solution to this problem? If you can include bounded Types and a sample in your solution that would be great.

public interface SmartDevice<T extends Os> {

  public Boolean installOs(T os);
}

public abstract class Phone implements SmartDevice<T extends Os>{

 @Override
 public Boolean installOs(T t) {
  //Cant implement it here since I dont know what device i am dealing with
 }
}

public class ApplePhone extends Phone<ios>  {

@Override
public Boolean installOs(ios os) {
  //this is an Apple phone so its ok to install ios in it.

    System.out.println("Installing Os: "+os.getName());
    return true;
}
}

Answer 1

I just found out that I could put an abstract method in my interface!

so all I needed all along was

public interface SmartDevice<T extends Os> {
  public abstract Boolean installOs(T os);
}

Then I went to the phone class and changed bounded types to this:

public abstract class Phone<A extends Os> implements SmartDevice<A>{

@Override
public abstract Boolean installOs(A s) ;

}

Thank you for your help guys.