Exception in thread "main" java.lang.ClassCastException: java.lang.StringBuilder cannot be cast to java.lang.Comparable
at java.util.Collections$ReverseComparator.compare(Collections.java:5108)
at java.util.TimSort.countRunAndMakeAscending(TimSort.java:351)
at java.util.TimSort.sort(TimSort.java:216)
at java.util.Arrays.sort(Arrays.java:1512)
at java.util.ArrayList.sort(ArrayList.java:1454)
at java.util.Collections.sort(Collections.java:175)
at WhatISThis.main(Main.java:15)