@Test
    public void shouldExtractKeys() {
        final Set<String> keys = ElementHelper.getKeys("test1", "something", "test2", "something else");
        assertTrue(keys.contains("test1"));
        assertTrue(keys.contains("test2"));
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/structure/util/ElementHelperTest.java