ByThorben JanssenRepresenting associations between entities as attributes is one of the most comfortable and popular features of JPA and Hibernate. It makes it very easy to navigate from one entity to one or more associated entities in your Java code, like from a Person entity to the corresponding Address entity. You can also use the association…
ByThorben JanssenMost Java EE applications are stateless and there are good reasons for it. But not all user interactions can be implemented in that way. Sometimes you need to model a conversation that consists of multiple steps, like the typical shopping cart or complex update operations. Doing this with JPA 2.0 always felt a little bit…
ByThorben JanssenWhen you write a criteria query or create a dynamic entity graph, you need to reference the entity classes and their attributes. The quickest and easiest way is to provide the required names as Strings. But this has several drawbacks, e.g. you have to remember or look-up all the names of the entity attributes when you write the query….
ByThorben JanssenYour entity classes map a database schema, which must be created before or during application startup. You can do this in various ways. You can run your own scripts, use tools like Flyway or Liquibase, or use the schema generation feature defined by the Jakarta Persistence specification (JPA). In this article, you will learn how…
ByThorben JanssenJava 8 brought lots of great features and one of the most important and most anticipated ones was the new Date and Time API. There were lots of issues with the old API and I won’t get into any details on why we needed a new one. I’m sure you had to struggle often enough…