@Test(groups = { "unit" }, expectedExceptions = IllegalStateException.class)

public void invalidRoutingMap() {
    InMemoryCollectionRoutingMap.tryCreateCompleteRoutingMap(Arrays.asList(
            new ImmutablePair<>(new PartitionKeyRange("1", "0000000020", "0000000030"),
                                ServerIdentityImp.of(2)),
            new ImmutablePair<>(new PartitionKeyRange("2", "0000000025", "0000000035"),
                                ServerIdentityImp.of(2))),
            StringUtils.EMPTY);
}