My EJB Bean

BeanLocator.java

public class BeanLocator implements ServiceLocator {

	@Override
	public Object getInstance(Class<?> clazz) {
		System.out.println(clazz);
		if (clazz.equals(GroupManager.class)) {
			return lookupBean(clazz, "GroupManager");
		} else {
			return null;
		}
	}

	private static <T> T lookupBean(Class<T> clazz, String name) {
		try {
			return (T) InitialContext.doLookup("java:global/kfc-frontend/" + name);
		} catch (NamingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return null;
		}
	}
}

Group.java

@Entity
@Table(name = "groups")
@NamedQueries({
        @NamedQuery(name = Group.retrieveAll, query = "SELECT g FROM Group g"),
        @NamedQuery(name = Group.retrieveByToken, query = "SELECT g FROM Group g "
                + "WHERE g.token = :token") })
public class Group {

    public static final String retrieveAll = "retrieveAll";
    public static final String retrieveByToken = "retrieveByToken";

    @Id
    @Column(name = "id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(name = "token", unique = true)
    private String token;

    @Column(name = "name")
    private String name;

    @OneToMany(mappedBy = "organizer")
    private List<Program> programs;

    @OneToMany(mappedBy = "producer")
    private List<Food> foods;

    @Version
    @Column(name = "version")
    private Integer version;

    public Long getId() {
        return this.id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getToken() {
        return token;
    }

    public void setToken(String token) {
        this.token = token;
    }

    public String getName() {
        return this.name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public List<Program> getPrograms() {
        return programs;
    }

    public void setPrograms(List<Program> programs) {
        this.programs = programs;
    }

    public List<Food> getFoods() {
        return foods;
    }

    public void setFoods(List<Food> foods) {
        this.foods = foods;
    }

    public Integer getVersion() {
        return version;
    }

    public void setVersion(Integer version) {
        this.version = version;
    }
}

GroupManager.java

@Stateless
@LocalBean
public class GroupManager extends Locator<Group, Long> {

	@PersistenceContext
	private EntityManager em;

	public Group findGroup(Long id) {
		return null;
	}
	
	public Group findByToken(String token) {
		return em.createNamedQuery(Group.retrieveByToken, Group.class)
				.setParameter("token", token).getSingleResult();
	}

	public List<Group> findGroups() {
		return em.createNamedQuery(Group.retrieveAll, Group.class)
				.getResultList();
	}

	@Override
	public Group create(Class<? extends Group> clazz) {
		return new Group();
	}

	@Override
	public Group find(Class<? extends Group> clazz, Long id) {
		System.out.println(em);
		System.out.println(clazz);
		System.out.println(id);
		return em.find(clazz, id);
	}

	@Override
	public Class<Group> getDomainType() {
		return Group.class;
	}

	@Override
	public Long getId(Group domainObject) {
		return domainObject.getId();
	}

	@Override
	public Class<Long> getIdType() {
		return Long.class;
	}

	@Override
	public Object getVersion(Group domainObject) {
		return domainObject.getVersion();
	}
}

GroupProxy.java

@ProxyFor(value = Group.class, locator = GroupManager.class)
public interface GroupProxy extends EntityProxy {

    String getToken();

    void setToken(String token);

    String getName();

    void setName(String name);
    
    List<ProgramProxy> getPrograms();

    EntityProxyId<GroupProxy> stableId();
}

GroupRequest.java

@Service(value = GroupManager.class, locator = BeanLocator.class)
public interface GroupRequest extends RequestContext {

    Request<GroupProxy> findGroup(Long id);

    Request<GroupProxy> findByToken(String groupToken);

    Request<List<GroupProxy>> findGroups();
}

TestServlet.java

@WebServlet("/Test")
public class Test extends HttpServlet {
	private static final long serialVersionUID = 1L;

	@EJB
	GroupManager groupManager;

	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		PrintWriter writer = response.getWriter();
		writer.println(groupManager.find(Group.class, 3L).getName());
	}
}