Java interface extends Comparable

Question

I want to have an interface A parameterised by T A, and also want every class that implements it to also implement Comp

Answer 1

If you use comparable you do not need to specify the possibility for subtypes in the compare function, it is by nature possible to pass in any subtype of an object X into a method that declared a parameter of class X. See the code below for more information.

public interface Test extends Comparable {

}

class TestImpl implements Test {
    @Override
    public int compareTo(final Number other) {
        return other.intValue() - 128;
    }
}

class TestMain {
    public static void main(final String[] args) {
        TestImpl testImpl = new TestImpl();
        testImpl.compareTo(Integer.MIN_VALUE);
    }
}