As expected, the recent release of the JPA 2.2 specification introduced official support for some of the classes of the Date and Time API. Before that, you had to rely on proprietary features, like the ones introduced in Hibernate 5, or you had to provide an AttributeConverter to implement the mapping. Let’s take a closer…
When you model your database, you will most likely define several many-to-one or one-to-many associations. And it’s, of course, the same when you model your entities. It’s quite easy to do that with JPA and Hibernate. You just need an attribute that represents the association and annotate it with a @ManyToOne or @OneToMany association. But…
JPA and Hibernate allow you to use DTOs and entities as projections in your JPQL and Criteria queries. When I talk about Hibernate performance in my online training or at a workshop, I get often asked, if it matters which projection you use. The answer is: YES! Choosing the right projection for your use case…
One of the benefits of using JPA and Hibernate is that it provides an abstraction of database-specific dialects and features. So, in theory, you can implement an application, connect it to one of the supported databases and it will run without any code changes. Hibernate does that really well. But let’s be honest, you didn’t…
The CascadeTypes REMOVE and ALL, which includes REMOVE, provide a comfortable option to remove an entity together with all its child entities. But it creates several issues for to-many associations, and you should only use it for to-one relationships.