public void givenListContainsDuplicates_whenRemovingDuplicatesWithJava8_thenCorrect() { List<Integer> listWithDuplicates = Lists.newArrayList(1, 1, 2, 2, 3, 3); List<Integer> listWithoutDuplicates = listWithDuplicates.stream() .distinct() .collect(Collectors.toList()); }