private Comparator getBugInstanceComparator(String sortOrder) {
private Comparator<BugInstance> getBugInstanceComparator(String sortOrder) {
    private Comparator getBugInstanceComparator(String sortOrder) {        if (sortOrder.equals(GROUP_BY_CLASS))            return bugInstanceByClassComparator;        else if (sortOrder.equals(GROUP_BY_PACKAGE))            return bugInstanceByPackageComparator;        else if (sortOrder.equals(GROUP_BY_BUG_TYPE))            return bugInstanceByTypeComparator;        else            throw new IllegalArgumentException("Bad sort order: " + sortOrder);    }