public void map(Void key, Activity val, Collector<String, ASObject> context) {
String ot = val.getActor().getDisplayName();
context.collect(ot != null ? ot : "", val.getActor());
}
private Activity getActivity(String name, int n) {
return Activity.makeActivity()
.actor(PersonObject.makePerson(name))
.id(String.format("urn:%s:%s", name, n))
.get();
}