@Test
    public void shouldConvertNullToIterator() {
        Iterator itty = IteratorUtils.asIterator(null);

        assertEquals(null, itty.next());
        assertFalse(itty.hasNext());
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/iterator/IteratorUtilsTest.java