@Test
public void createThingWithoutCreated() {

    final Thing thing = ImmutableThing.of(THING_ID, ACL, ATTRIBUTES, FEATURES, LIFECYCLE, REVISION, MODIFIED, null, 
            METADATA);
    assertThat(thing)
            .hasId(THING_ID)
            .hasAcl(ACL)
            .hasAttributes(ATTRIBUTES)
            .hasFeatures(FEATURES)
            .hasLifecycle(LIFECYCLE)
            .hasRevision(REVISION)
            .hasModified(MODIFIED)
            .hasNoCreated();
}