@Test
public void givenList_whenParitioningIntoSublistsUsingPartitionBy_thenCorrect() {
    List intList = Lists.newArrayList(1, 2, 3, 4, 5, 6, 7, 8);

    Map> groups = 
      intList.stream().collect(Collectors.partitioningBy(s -> s > 6));
    List> subSets = new ArrayList>(groups.values());

    List lastPartition = subSets.get(1);
    List expectedLastPartition = Lists. newArrayList(7, 8);
    assertThat(subSets.size(), equalTo(2));
    assertThat(lastPartition, equalTo(expectedLastPartition));
}