TL;DR: all code is directly available on GitHub: https://github.com/damienbeaufils/spring-data-jpa-encryption-example
Each time I want to encrypt entity fields values with JPA converters, I end up reading this blog post. This example is clear and functional, but has no unit or integration tests, and I thought the code could be more decoupled to avoid duplication when having multiple converters.
So I wrote an example using Spring Boot and Spring Data JPA, with a User entity which have different fields: id (a Long), firstName (a String), lastName (a String), email (a String), birthDate (a LocalDate) and creationDate (a LocalDateTime).