我正在尝试从休眠3迁移到5.2.3,并且有许多调用org.hibernate.SessionFactory.getAllClassMetadata的旧代码,该方法已在休眠5中弃用,建议使用SessoinFactory.getMetaModel(),但是当我尝试调用此方法时,似乎也已弃用,我将继续研究,找不到建议使用的任何其他方法,有人可以帮助吗?如果您能提供详细用法,将不胜感激,谢谢。

这是getAllClassMetadata的用法:

@Override
    public Collection<ModelSpecificationSummary> findAllModelSpecificationSummaries() throws RepositoryException {
        List<ModelSpecificationSummary> summaries = new ArrayList<ModelSpecificationSummary>();
        try {
            Query query = session.createQuery(
                            "selecc.name, spec.class from " + Specification.class.getSimpleName() + " spec");
            List<Object[]> list = query.list();

            SingleTableEntityPersister metadata = (SingleTableEntityPersister) session.getSessionFactory()
                            .getAllClassMetadata()
                            .get(Specification.class.getName());
            for (Object[] o : list) {
                Long id = (Long) o[0];
                String name = (String) o[1];
                String discriminator = (String) o[2];

                Class<? extends ModelSpecification> specificationClass = lookupSpecificationSubclass(metadata, discriminator);

                ModelSpecificationSummary summary = new ModelSpecificationSummary(id, name, specificationClass);
                summaries.add(summary);
            }

            return summaries;
        }
        catch (HibernateException he) {
            throw new RepositoryException(he);
        }
    }


和lookupSpecificationSubclass类:

 private Class<? extends ModelSpecification> lookupSpecificationSubclass(SingleTableEntityPersister metadata,
                                                                            String discriminator)
                    throws RepositoryException {
        Class<? extends ModelSpecification> specificationClass = null;

        String subclass = metadata.getSubclassForDiscriminatorValue(discriminator);
        if (subclass != null) {
            try {
                specificationClass = (Class<? extends ModelSpecification>) Class.forName(subclass);
            }
            catch (ClassNotFoundException e) {
                throw new RepositoryException("Invalid class found for specification " + discriminator, e);
            }
        }
        else {
            throw new RepositoryException("No class found for specification " + discriminator);
        }
        return specificationClass;
    }


所以我怎么想用getAllClassMetadata()替换EntityManagerFactory.getMetamodel()

最佳答案

根据SessionFactory#getAllClassMetadata文档:


  不推荐使用。使用EntityManagerFactory.getMetamodel()中的描述符


请注意,它建议使用不建议使用的EntityManagerFactory#getMetamodel。您可以在网上找到许多说明如何使用它的示例,也可以提出一个具体的问题来确切地希望使用它实现什么。

10-08 04:47