if (ops == null) {
return EMPTY_ARR;
}
Set<String> features = Sets.newHashSet();
for (Operator<?> op : ops) {
OperatorType opType = op.getType();
// some operators are discarded
if (!skipType(opType)) {
features.add(opType.toString());
}
}
// if taskTag is other than 'NO_TAG', include it in the feature list
if (taskTagId == Task.NO_TAG) {