@Override
    public void reset() {
        if (!kryo.isRegistrationRequired()) {
            if (classToNameId != null) classToNameId.clear();
            if (nameIdToClass != null) nameIdToClass.clear();
            nextNameId = 0;
        }
    }
Called from {@link #getRegistration(Class)} to determine the actual type.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/io/gryo/AbstractGryoClassResolver.java