Direct comparator in Java out of the box
- by KARASZI István
I have a method which needs a Comparator for one of its parameters. I would like to pass a Comparator which does a normal comparison and a reverse comparator which does in reverse.
java.util.Collections provides a reverseOrder() this is good for the reverse comparison, but I could not find any normal Comparator.
The only solution what came into my mind is Collections.reverseOrder(Collections.reverseOrder()). but I don't like it because the double method calling inside.
Of course I could write a NormalComparator like this:
public class NormalComparator<T extends Comparable> implements Comparator<T> {
public int compare(T o1, T o2) {
return o1.compareTo(o2);
}
}
But I'm really surprised that Java doesn't have a solution for this out of the box.
