private Comparator getGroupComparator(String groupBy) {
private Comparator<BugInstance> getGroupComparator(String groupBy) {
    private Comparator getGroupComparator(String groupBy) {        if (groupBy.equals(GROUP_BY_CLASS)) {            return bugInstanceClassComparator;        } else if (groupBy.equals(GROUP_BY_PACKAGE)) {            return bugInstancePackageComparator;        } else if (groupBy.equals(GROUP_BY_BUG_TYPE)) {            return bugInstanceTypeComparator;        } else            throw new IllegalArgumentException("Bad sort order: " + groupBy);    }