public void testOrdering() {
        for (int i = 0; i < groups.size(); i++) {
            for (T item : groups.get(i)) {
                for (T otherItem : groups.get(i)) {
                    equalTest(item, otherItem);
                }
            }

            for (int j = i+1; j < groups.size(); j++) {
                for (T lessItem : groups.get(i)) {
                    for (T greaterItem : groups.get(j)) {
                        lessTest(lessItem, greaterItem);
                        greaterTest(greaterItem, lessItem);
                    }
                }
            }
        }
    }
Test the ordering defined with {@link OrderTester#theseObjects} and {@link OrderTester#areLessThan}
with respect to T#compareTo and the {@link OrderTester} subclass (e.g. {@link com.yahoo.test.TotalOrderTester}).
testutil/src/main/java/com/yahoo/test/OrderTester.java