@Test
public void shouldConcatenateIterators() throws Exception {

    Iterable<String> a = Arrays.asList("a", "b", "c");
    Iterable<String> b = Arrays.asList("1", "2", "3");
    final Iterator<String> iterator = Collections.concat(a.iterator(), b.iterator());
    assertThat(iterator, hasItems("a", "b", "c", "1", "2", "3"));
}