冬眠，因为它:

是稳定的-存在了这么多年，它没有任何大的问题 规定了ORM领域的标准 实现标准(JPA)，并对其进行口述。 网上有很多关于它的信息。有许多教程，常见问题的解决方案等 功能强大—您可以将非常复杂的对象模型转换为关系模型。 它支持任何主要和中型RDBMS 一旦你学会了它，就很容易使用

关于为什么(以及何时)使用ORM的几点:

you work with objects in your system (if your system has been designed well). Even if using JDBC, you will end up making some translation layer, so that you transfer your data to your objects. But my bets are that hibernate is better at translation than any custom-made solution. it doesn't deprive you of control. You can control things in very small details, and if the API doesn't have some remote feature - execute a native query and you have it. any medium-sized or bigger system can't afford having one ton of queries (be it at one place or scattered across), if it aims to be maintainable if performance isn't critical. Hibernate adds performance overhead, which in some cases can't be ignored.

Eclipse Link，有很多原因，但值得注意的是，我觉得它比其他主流解决方案的膨胀要小(至少不那么让人头疼)。

哦，Eclipse Link已被选为JPA 2.0的参考实现

我已经停止使用orm了。

原因并不是这个概念有什么大缺陷。Hibernate工作得很好。相反，我发现查询的开销很低，我可以将大量复杂的逻辑放入大型SQL查询中，并将大量处理转移到数据库中。

因此，请考虑只使用JDBC包。

我建议使用MyBatis。它是JDBC之上的一个薄层，它很容易将对象映射到表，并且仍然使用纯SQL，一切都在您的控制之下。

当我在编写一个中等大小的JavaSE应用程序时，我对Avaje Ebean有过很好的体验。

它使用标准JPA注释来定义实体，但公开了一个更简单的API(没有EntityManager或任何附加/分离实体之类的废话)。它还允许您在必要时轻松使用SQL查询或事件纯JDBC调用。

它还为查询提供了一个非常好的流动和类型安全的API。你可以这样写:

List<Person> boys = Ebean.find(Person.class)
                                  .where()
                                       .eq("gender", "M")
                                       .le("age", 18)
                                  .orderBy("firstName")
                                  .findList();

SimpleORM，因为它是直接的，没有魔法。它在Java代码中定义了所有元数据结构，非常灵活。

SimpleORM provides similar functionality to Hibernate by mapping data in a relational database to Java objects in memory. Queries can be specified in terms of Java objects, object identity is aligned with database keys, relationships between objects are maintained and modified objects are automatically flushed to the database with optimistic locks. But unlike Hibernate, SimpleORM uses a very simple object structure and architecture that avoids the need for complex parsing, byte code processing etc. SimpleORM is small and transparent, packaged in two jars of just 79K and 52K in size, with only one small and optional dependency (Slf4j). (Hibernate is over 2400K plus about 2000K of dependent Jars.) This makes SimpleORM easy to understand and so greatly reduces technical risk.