package test; 

import java.io.Serializable; 
import java.util.Comparator; 

interface Example { 

    static void main(String[] args) { 
        Comparator<String> comparator = comparator(); 
        System.out.println(comparator.compare("a", "b") == -1); 
    } 

    static <T extends Comparable<? super T>> Comparator<T> comparator() { 
        return (Comparator<T> & Serializable) T::compareTo; 
    } 

}