Question

我有两个名为“地址和客户”的实体。我有一个界面看起来像：

public interface IDAOEnitityFactory extends Serializable{
List<Address> findAllByClass();
}

实现如下：

 @Stateless
@Local(IDAOEnitityFactory.class)
 public class DAOEnitityFactory implements IDAOEnitityFactory {
@PersistenceContext(unitName = "MY_PU")
protected EntityManager entityManager;

@Override
public List<Address> findAllByClass() {     
    return this.getAuditReader().createQuery()
            .forRevisionsOfEntity(Address.class, true, false)
            .setMaxResults(10).getResultList();
}

所以我想做一个通用的实现，我只传递Adress或Client和findAllByClass返回它们。我怎么能这样做？

我有一个豆子：

@EJB
private IDAOEnitityFactory dao;
for(Address st:dao.findAllByClass()){
                System.out.println(st.getID);               
            }

Answer 1

我认为我找到了解决方案：

public interface IDAOEnitityFactory extends Serializable{
T List<T> findAllByClass(Class c);
 }

@Stateless
@Local(IDAOEnitityFactory.class)
public class DAOEnitityFactory implements IDAOEnitityFactory {
@PersistenceContext(unitName = "MY_PU")
protected EntityManager entityManager;
@Override
public List<T> findAllByClass(Class c) {     
return this.getAuditReader().createQuery()
        .forRevisionsOfEntity(c, true, false)
        .setMaxResults(10).getResultList();
 }

@EJB
private IDAOEnitityFactory dao;
for(Object st:dao.findAllByClass(Address.class)){
            System.out.println((Address)st)st.getID);               
        }

也许还有其他解决方案。母鸡？

如何制作通用EJB类

1 个答案: