Sorting set of string numbers in java -

i need sort set of string's holds number.ex: [15, 13, 14, 11, 12, 3, 2, 1, 10, 7, 6, 5, 4, 9, 8]. need sort [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]. when use collections.sort(keylist); keylist set, reult obtained [1, 10, 11, 12, 13, 14, 15, 2, 3, 4, 5, 6, 7, 8, 9]. please help.

write custom comparator , parse argument collections.sort(collection,comparator). 1 solution parsing strings integers.

    collections.sort(keylist, new comparator<string>()     {         @override         public int compare(string s1, string s2)         {             integer val1 = integer.parseint(s1);             integer val2 = integer.parseint(s2);             return val1.compareto(val2);         }     });