Unchecked conversion warning - What is the proper way to fix this?

Question

I've been trying to figure this out for awhile now, and I have not seen an example that will set me on the right track. Given the following code:
        public TreeSet<String> sort = new TreeSet<String>(CI_NE_Comparator);
        public static Comparator CI_NE_Comparator = new CaseInsensitiveNeverEqualsComparator();
        public static class CaseInsensitiveNeverEqualsComparator implements Comparator
          public int compare(Object o1, Object o2)
               String s1 = (String) o1;
               String s2 = (String) o2;
               int compare = s1.trim().toLowerCase().compareTo(s2.trim().toLowerCase());
               if (compare == 0)
                    return 1; // ensure like values are never deemed equal
               return compare;
     }I'm getting a warning declaring the class variable sort:
Type safety: The expression of type Comparator needs unchecked conversion to conform to Comparator <? super String>
So just what is the proper method to make the Comparator conform to generics?
** Btw - if anyone knows of a better way to do that comparator, I'm all ears!

Answer 1

Why don't you want like values to be deemed equal?
What would be wrong with using
String.CASE_INSENSITIVE_ORDER?The code you see above is a stripped down example. We have the need to present data records in alphabetical order to a user, and sometimes these records have the same dscr, but that doesn't necessarily mean it's a unique record. Because of the backing query, I can't rely on the order in which the records were received.
I can't modify the queries. Also, I can't modify the 30 or so different types of data records, all having the common field dscr, so that I can write a better implementation. But, I can write a better comparator.
This is all legacy code that I've been working with, so I have to make sure things work as they did before.