How to use Comparator in Java to sort

Question

I learned how to use the comparable but I\'m having difficulty with the Comparator. I am having a error in my code:

Exception in thread \"main\" java.lang.C         


        

Answer 1

For the sake of completeness, here's a simple one-liner compare method:

Collections.sort(people, new Comparator() {
    @Override
    public int compare(Person lhs, Person rhs) {  
        return Integer.signum(lhs.getId() - rhs.getId());  
    }
});