How to increment the parent entity version whenever a child entity gets modified with JPA and Hibernate
Introduction StackOverflow and the Hibernate forum are gold mines. Yesterday, I bumped on the following question on our forum: Usually, the rationale behind clustering objects together is to form a transactional boundary inside which business invariants are protected. I’ve noticed that with the OPTIMISTIC locking mode changes to a child entity will not cause a version increment on the root. This behavior makes it quite useless to cluster objects together in the first place. Is there a way to configure Hibernate so that any changes to an object cluster will cause the… Read More
High-Performance Java Persistence – Part Three
100% done The third part of High-Performance Java Persistence book is out. It’s been one year and two months since I started writing this book, and nine months since I published the first part.
JPA providers market share in 2016
The survey Java Persistence API is a standard. Hence, there are multiple options to choose from: Hibernate EclipseLink OpenJPA Some applications choose not to use an ORM framework at all. For this reason, I decided to run a one-day survey on Twitter to get a glimpse on the JPA providers market share.
Fluent API entity building with JPA and Hibernate
Introduction In this article, we are going to see how we can build an entity in a fluent style API fashion when using JPA and Hibernate. The JHipster development team wants to expose a Fluent Interface entity building methods for their JPA entities, so they asked me if this is going to work with JPA and Hibernate. While JPA is rather strict about entity getters and setter, Hibernate is more lenient in this regard.
The best way to map a Composite Key with JPA and Hibernate
Introduction One of my readers asked me to help him map a Composite Key using JPA and Hibernate. Because this is a recurrent question, I decided to write a blog post in which I describe this mapping in more detail.
The best way to map a @OneToOne relationship with JPA and Hibernate
Introduction In this article, we are going to learn the best way to map a OneToOne association with JPA and Hibernate. While there are many ways you can map a one-to-one relationship with Hibernate, I’m going to demonstrate which mapping is the most efficient one from a database perspective.
How do persist and merge work in JPA
Introduction In this article, I’m going to explain how the persist and merge entity operations work when using JPA and Hibernate. When using JPA, entity state transitions are translated automatically to SQL statements. This post is going to explain when to use persist and when to use merge.
The best way to detect database connection leaks
Introduction Database connections are not free, and that’s the reason for using a connection pooling solution in the first place. However, the connection pool alone does not solve every issue associated to managing database connections. The application developer must make sure that every Connection is closed when no longer needed. Behind the scenes, the connection pool gives a logical transaction which, when being closed, it returns back to the pool so that it can be further reused by other concurrent transactions. A connection leak happens when a connection is acquired without ever… Read More
How to lazy load entity properties with Hibernate
Introduction One of my readers bumped into the JSON mapping post and asked me if we can fetch the JSON properties lazily. This post demonstrates how easily this can be done when using Hibernate as a JPA provider. As I previously explained, EAGER fetching is a code smell and loading associations eagerly is very detriment to application performance. However, it’s not just associations that we must be careful about. Basic entity properties may also cause performance issues as well. In this post, I’m going to show you how you can fetch entity… Read More
14 High-Performance Java Persistence Tips
Introduction In this article, I’m going to show you various high-performance Java Persistence optimization tips that will help you get the most out of your data access layer. A high-performance data access layer requires a lot of knowledge about database internals, JDBC, JPA, Hibernate, and this post summarizes some of the most important techniques you can use to optimize your enterprise application. 1. SQL statement logging If you’re using a framework that generates statements on your behalf, you should always validate the effectiveness and efficiency of each executed statement. A testing-time assertion… Read More
