### Question:
RackDAO extends DefaultDAOBase<Integer, Rack> { @SuppressWarnings("unchecked") public List<Integer> findUsedVrdpPorts(final Rack rack) { Query query = getSession().createQuery(QUERY_USED_VDRP); query.setParameter("rack", rack); return query.list(); } RackDAO();  RackDAO(final EntityManager entityManager); List<Rack> findRacks(final Datacenter datacenter); List<Rack> findRacks(final Datacenter datacenter, final String filter); List<Rack> findRacksWithHAEnabled(final Datacenter datacenter); boolean existsAnyWithDatacenterAndName(final Datacenter datacenter, final String name); boolean existsAnyOtherWithDatacenterAndName(final Rack rack, final String name); List<Integer> getRackIdByMinVLANCount(final int idDatacenter); Long getNumberOfDeployedVlanNetworks(final Integer rackId); Rack findByIds(final Integer datacenterId, final Integer rackId); List<Rack> findAllNotManagedRacksByDatacenter(final Integer datacenterId); List<Rack> findAllNotManagedRacksByDatacenter(final Integer datacenterId,
        final String filter); @SuppressWarnings("unchecked") List<Integer> findUsedVrdpPorts(final Rack rack); Integer getEmptyOffMachines(final Integer rackId); Integer getEmptyOnMachines(final Integer rackId); List<Machine> getRandomMachinesToStartFromRack(final Integer rackId,
        final Integer howMany); List<Machine> getRandomMachinesToShutDownFromRack(final Integer rackId,
        final Integer howMany); List<Machine> getAllMachinesToShutDownFromRack(final Integer rackId);  }### Answer:
@Test public void test_findUsedVrdpPorts() { VirtualMachine vm1 = vmgenerator.createUniqueInstance(); VirtualMachine vm2 = vmgenerator.createInstance(vm1.getVirtualMachineTemplate(), vm1.getEnterprise(), vm1.getHypervisor(), vm1.getUser(), "test"); Category category = new Category("test-category"); vm1.getVirtualMachineTemplate().setCategory(category); List<Object> entitiesToPersist = new ArrayList<Object>(); vmgenerator.addAuxiliaryEntitiesToPersist(vm1, entitiesToPersist); persistAll(ds(), entitiesToPersist, vm1, vm2); Rack rack = vm1.getHypervisor().getMachine().getRack(); RackDAO dao = createDaoForRollbackTransaction(); List<Integer> usedPorts = dao.findUsedVrdpPorts(rack); assertEquals(usedPorts.size(), 2); }