java - Making a generic comparator class - Stack Overflow

java - Making a generic comparator class - Stack Overflow

The closest thing you can do to this is a Comparator that can compare any objects that implement the Comparable interface:

class NaturalComparator<T extends Comparable<T>> implements Comparator<T> {    public int compare(T a, T b) {      return a.compareTo(b);    }  }

That's really the closest you can do: only Comparable objects have the "natural ordering" you're trying to model here. But generally, once you have Comparable objects, you don't necessarily need a Comparator: for example, Collections.sort can take either a List with a Comparator, or a List with Comparable elements.

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