@Override
    public Q addFetchGroup(String fetchGroupName) {
        fetchGroups.add(fetchGroupName);
        return queryMixin.getSelf();
    }
Add the fetch group to the set of active fetch groups.

@param fetchGroupName fetch group name
@return the current object
querydsl-jdo/src/main/java/com/querydsl/jdo/AbstractJDOQuery.java