eclipselink

eclipselink is originally TopLink, EclipseLink is the reference implementation for JPA. Supports more than RDMS, as does Hibernate, and if Hibernate has a JPA competitor, you just found it. Has slightly better batching and large dataset performance than Hibernate, but if you don't know about it, learning about it's going to be fun.
jpa, orm, persistence, jakarta-ee, eclipse