How to map a PostgreSQL Enum ARRAY to a JPA entity property using Hibernate

Introduction The open-source hibernate-types project allows you to map JSON, ARRAY, YearMonth, Month or database-specific columns (e.g. INET addresses). In this article, we are going to see how you can map a PostgreSQL Enum ARRAY type to a Java array entity property when using JPA and Hibernate.

How to bind custom Hibernate parameter types to JPA queries

Introduction In this article, we are going to see how we can bind a custom Hibernate parameter type to a JPA query. I decided to write this article after one of my hibernate-types framework users created this very interesting issue on GitHub.

How to intercept entity changes with Hibernate event listeners

Introduction In this article, we are going to see how the Hibernate event listeners work and how you add your custom listeners to intercept entity changes and replicate them to other database tables. Recently, one of my blog readers asked a very good question on StackOverflow. Since my main goal as a Hibernate Developer Advocate is to help Java developers get the most out of JPA and Hibernate, I decided that this is a good opportunity to talk about the Hibernate event listener mechanism.

The best way to initialize LAZY entity and collection proxies with JPA and Hibernate

Introduction In this article, we are going to see the best way to initialize LAZY proxies and collections when using JPA and Hibernate. I decided to write this article because there are way too many resources available on the Internet that mislead the reader into using awkward and inefficient practices.

How to execute SQL functions with multiple parameters in a JPQL query with Hibernate

Introduction In this article, we are going to see how you can execute SQL functions with multiple parameters in JPQL queries with Hibernate. I recently stumbled on this requirement while answering this StackOverflow question which is a never-ending source of inspiration for articles on my blog.

The best way to use the JPQL DISTINCT keyword with JPA and Hibernate

Introduction In this article, we are going to how the JPQL DISTINCT keyword behaves depending on the underlying entity query type.

How to map camelCase properties to snake_case column names with Hibernate

Introduction In this article, you are going to learn how to map cameCase entity properties (e.g. phoneNumber) to snake_case column names (e.g. phone_number) using a Hibernate naming strategy. While you could achieve the same goal with the name attribute of JPA @Column annotation, it’s much more convenient to use a custom Hibernate strategy to apply this naming convention consistently.

How to merge entity collections with JPA and Hibernate

Introduction In this article, you are going to learn why overwriting entity collections is an anti-pattern and how you can merge collections both effectively and efficiently with JPA and Hibernate. The reason I decided to write this article is that I’ve been this question asked over and over and over again.

How to map java.time.Year and java.time.Month with JPA and Hibernate

Introduction In this article, we are going to see how you can map the java.time.Year and java.time.Month with both JPA and Hibernate. As explained in this article, JPA 2.2 supports LocalDate, LocalTime, LocalDateTime, OffsetTime, OffsetDateTime from the java.time package. Hibernate has been supporting the Java 8 Date/Time classes since 5.0 via the hibernate-java8 dependency, but since version 5.2, this dependency was merged with hibernate-core so you get the Duration, Instant and ZonedDateTime types in addition to the ones supported by JPA 2.2. However, neither JPA nor Hibernate supports the java.time.Year type out-of-the-box…. Read More

How to map the Java YearMonth type with JPA and Hibernate

Introduction In this article, we are going to see how you can map a java.time.YearMonth with both JPA and Hibernate. As I explained in this article, JPA 2.2 supports the following Date/Time types introduced in Java 8: java.time.LocalDate java.time.LocalTime java.time.LocalDateTime java.time.OffsetTime java.time.OffsetDateTime Apart from supporting those, Hibernate supports also: java.time.Duration java.time.Instant java.time.ZonedDateTime However, neither JPA nor Hibernate support the java.time.YearMonth out-of-the-box. As you will see, adding support for java.time.YearMonth is really straightforward for both standard JPA or Hibernate.