public ImmutableSet<GrantDTO> getForGranteesOrGlobal(Set<GRN> grantees) {
        return streamQuery(DBQuery.or(
                DBQuery.in(GrantDTO.FIELD_GRANTEE, grantees),
                DBQuery.is(GrantDTO.FIELD_GRANTEE, GRNRegistry.GLOBAL_USER_GRN.toString())
        )).collect(ImmutableSet.toImmutableSet());
    }
@Test
    @MongoDBFixtures("grants.json")
    public void getForGranteesOrGlobal() {
        final GRN jane = grnRegistry.newGRN("user", "jane");
        final GRN john = grnRegistry.newGRN("user", "john");

        assertThat(dbService.getForGranteesOrGlobal(Collections.singleton(jane))).hasSize(4);
        assertThat(dbService.getForGranteesOrGlobal(Collections.singleton(john))).hasSize(3);
    }