Are variableLabels available from the Java client?

[Paul Chambre]

I am trying to understand how best to distinguish metrics that are associated with distinct instances of tasks in our system. I see that the (golang) systemd collector uses variableLabels to do this. 

E.g. node_systemd_unit_state{name="dh-etcd.service",state="active",type="notify"} 1

I would like to do something similar from the Java client, but I don't see any such attribute in Gauge.java, et al. The Java API seems to only allow numeric valued labels. Am I missing something? 

Thanks,
Paul