@Test(expected = FastNoSuchElementException.class)
    public void shouldAlwaysThrowFastNoSuchElementException() {
        EmptyIterator.instance().next();
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/util/iterator/EmptyIteratorTest.java