public static Set<String> getKeys(final Object... keyValues) {
        final Set<String> keys = new HashSet<>();
        for (int i = 0; i < keyValues.length; i = i + 2) {
            keys.add(keyValues[i].toString());
        }
        return keys;
    }
Gets the list of keys from the key values.

@param keyValues a list of key/values pairs
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/util/ElementHelper.java