A 205-test Hibernate suite run against Hibernate 8.0.0.Beta3 and Jakarta Persistence 4.0.0-M7: the classpath trap, the Spring blocker, removed APIs, a binary-compatibility break and the runtime changes that did and did not reproduce. Preview article, updated at GA.
The refined Specification API, AOT repository generation, and shared EntityManager wiring are the parts of the Spring Data JPA 3 to 4 migration that don't show up in a repository interface. Part 3 of the migration series covers DeleteSpecification/UpdateSpecification, JpaSort.unsafe, AOT knobs, and native-image implications.
Spring Data JPA 4 quietly moved derived queries off the Criteria API onto JPQL strings. Part 2 of the migration series covers the benchmark, getSingleResultOrNull, provider differences (with a real EclipseLink regression), the removed native-query parser, NULLS precedence, and which new JPQL functions are portable.
Part 1 of a 3-part Spring Data JPA 3 to 4 migration series. Covers the platform bump, the hibernate-jpamodelgen to hibernate-processor rename, repository interface compatibility, the JSpecify @NullMarked null-handling shift, and what genuinely doesn't change. Verified against Spring Boot 4.0.6 and Spring Data JPA 4.0.6.
A beginner-to-advanced guide to migrating the repository layer from Spring Data JPA 3 to 4 on Spring Boot 4.1: the hibernate-jpamodelgen → hibernate-processor coordinate swap and the silent metamodel failure it causes, why derived queries now generate JPQL instead of CriteriaQuery (and the getSingleResultOrNull edge case), records as @Embeddable value objects and projection targets, JSpecify nullability, the refined Specification API, and the removed config that breaks your build — all mapped to real code and errors on a Spring Boot 4.1 app.
I have now taken three codebases through the Hibernate 5 → 6 → 7 path, and the same pattern repeated each time: the compile errors are the easy part, and the silent behaviour changes — query result types, ID generation, fetch semantics — are what reach production. This guide walks the migration in two deliberate hops (5→6, then 6→7), with the exact errors you will see at each stage and how to fix them. Do not attempt 5→7 in one jump; the diagnostics assume you pass through 6.
10 copy-paste AI prompts for Hibernate and JPA development. Covers entity relationship design, fixing LazyInitializationException, writing JPQL queries, generating Flyway migrations, second-level cache, bulk operations, soft delete, auditing with @EntityListeners, Criteria API Specifications, and full entity model reviews.
Fix org.hibernate.query.sqm.internal.SqmUtil$NotYetImplementedException in Spring Boot JPA native queries. Covers interface projections, @SqlResultSetMapping, and JPQL constructor expressions with annotated code examples.
session.get() and session.getReference() look interchangeable at a glance, but the difference isn't "eager vs lazy" -- it's what you're telling Hibernate you need. This piece runs four calls against Hibernate 7.4.1.Final, builds the full same-session matrix, and pins down exactly where the proxy identity contract breaks -- including one same-session result that the usual L1-cache explanation gets wrong.
merge() and refresh() get described as opposite directions of the same tool -- one pushes, one pulls. Run them against a real @Version-ed entity and that framing misses the actual question: which one fails loudly when the state it's holding is stale? Three named experiments against Hibernate 7.4.1.Final, including a result that overturned the article's own original assumption.