Accessing superclass method of subclass through another class in java

Question

What is the best solution for this problem?

This is the superClass

public class Views<T> {

private T controller;

public Views() {
}

public Stage getStage(Node object){
    return (Stage) object.getScene().getWindow();
}

public T getController(){
    return controller;
}

public void setController(T controller){
    this.controller = controller;
}

}

I have this interface:

public interface UserView extends Observer{
    public void setLoginObjects(Parent root);
    public void loginStartUI() throws Exception;

    public void setCriarUserObjects(Parent root, User user);
    public void criarUserStartUI(User user) throws Exception;
}

I have this subclass of Views:

public class UserViewImpl extends Views<UserController> implements UserView{
...

And i have this class:

public class UserController {

private UserView view;
private UserDAOImpl model;

public UserController(UserView view, UserDAOImpl model) {
    this.model = model;
    this.view = view;
    view.setController(this);
    this.model.addObserver(view);
}
...

What is the best solution for this problem? Should i put together Views and UserView? (The problem for this solution is i will have more views, for example i have ParqueView and ParqueViewImpl, that basically will have the same methods as Views, so there would be repeated code and i want to avoid that)

The main problem is that inside my UserController i pass as parameter UserView, which does not have access to super class methods, and i need to access setController which is located in Views class, it doesnt make sense to change the type of UserView to Views in userController because of the MVC

"What is the best solution for this problem?" - You never explained what the problem is (the title does not suffice). — Jacob G., Dec 31 '18 at 18:53
Would `ParqueView` also have/need the methods from `UserView`? — Thiyagu, Dec 31 '18 at 18:55
@JacobG. sorry i though the problem was pretty obvious, ill edit the post! — Hugo Modesto, Dec 31 '18 at 18:56
You could make View an interface and make `UserView` implement it? — Thiyagu, Dec 31 '18 at 19:01
What precisely are you seeking to achieve by using generics? — Joe C, Dec 31 '18 at 19:03
@user7 hmm, it might work because then UserView would have the method that i want to access, but i create class Views to avoid code repetition :/ — Hugo Modesto, Dec 31 '18 at 19:04
@JoeC i use generics because, for UserViewImpl i will have UserController, for ParqueViewImpl i will have ParqueController — Hugo Modesto, Dec 31 '18 at 19:05
Might sound crazy - You can have one class called `ObservableView` that implemetns View and extends Observer and make `UserView` extend that. But I don't want to solve a [XY problem](https://meta.stackexchange.com/questions/66377/what-is-the-xy-problem) here. We need to understand the class model to understand more. — Thiyagu, Dec 31 '18 at 19:08

score 0 · Answer 1 · answered Dec 31 '18 at 19:08

0

It looks like you do not need generics here. Simply using an interface should suffice.

Create a Controller interface, which your two controllers will implement. Then you can get rid of the <T> entirely and use this interface instead.

answered Dec 31 '18 at 19:08

Joe C

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Accessing superclass method of subclass through another class in java

1 Answers1