"how to refer subclass variable without declaring that variable in parent class?" 上的扩展问题

Question

public class Test {
    public static void main(final String[] args) {
    B b = new B();
    System.out.println(b);
    }
}

interface MyInterface<T> {
    int getX();
}

abstract class A implements MyInterface {
    @Override
    public String toString() {
    return String.valueOf(getX());
    }
}

class B extends A, implements MyInterface<C> {
    private static final int X = 10;

    @Override
    public int getX() {
    return X;
    }
}

class C  {
    // This is concrete class some 
}

我无法使用泛型增强此界面。它在抽象 class 或实现 class 处抛出错误。我怎样才能让它成为可能？

Answer 1

你的意思是这样的吗？

public class Test {
    public static void main(final String[] args) {
        MyInterface b = new B();
        System.out.println(b);
    }
}

interface MyInterface<T> {
    T getX();
}

abstract class A<T> implements MyInterface {
    @Override
    public String toString() {
        return String.valueOf(getX());
    }
}

class B extends A {
    //private static final int X = 10;
    private static final double X = 10;

    //@Override
    public Double getX() {
        return X;
    }
}

Answer 2

public class MyTest2 {
    public static void main(final String[] args) {
    B b = new B();
    System.out.println(b);
    }
}

interface MyInterface<T> {
    int getX();
}

abstract class A<T> implements MyInterface {
    @Override
    public String toString() {
    return String.valueOf(getX());
    }
}

class B extends A<C>  {
    private static final int X = 10;

    @Override
    public int getX() {
    return X;
    }
}

class C  {
    // This is concrete class some
}

"how to refer subclass variable without declaring that variable in parent class?" 上的扩展问题

Extended Queesion on "how to refer subclass variable without declaring that variable in parent class?"

java

oop

polymorphism

inheritance

abstract