Add Spring Data Jsr310JpaConverters (JDK8 dates) automatically to @EntityScan if applicable

[marceloverdijk]

With latest Spring Data 1.8 (Fowler) release, Spring Data provides convenient JDK8 data converters via org.springframework.data.jpa.convert.threeten.Jsr310JpaConverters.

To apply these automatically I have to to add the following to a configuration class:

@EntityScan(basePackageClasses = {Application.class, Jsr310JpaConverters.class})

It would be very nice if Spring Boot could add these Jsr310JpaConverters.class automatically to the entity scan process. Just like it would add the Application.class automatically if I would not provide the @EntityScan annotation.

Of course this should only be done if applicable; e.g. using JDK8 and Spring Data JPA.

Depends on: #2721

[marceloverdijk]

Also see this stackoverflow thread for reference: http://stackoverflow.com/questions/29241575/new-spring-data-jdk8-jsr310jpaconverters-not-working-automatically

[philwebb]

Also ThreeTenBackPortJpaConverters and see https://spring.io/blog/2015/03/26/what-s-new-in-spring-data-fowler

[wilkinsona]

This isn't quite as straightforward as I thought. Using @EntityScan on one of our configuration classes has the unwanted side-effect of switching off the default which is retrieved from AutoConfigurationPackages

[thomasdarimont]

Couldn't you just add the Jsr310Converters dynamically in EntityScanRegistrar.getPackagesToScan(..).
This wouldn't have the mentioned side-effect IMHO.
But I that probably isn't called if no @EntityScan is present...

Perhaps you could add the Converters in EntityManagerFactoryBuilder.Builder.build().

[wilkinsona]

Perhaps you could add the Converters in EntityManagerFactoryBuilder.Builder.build().

I don't really want EntityManagerFactoryBuilder to know anything about Spring Data JPA

[thomasdarimont]

Sure - you're right (although it actually comes from SD Commons but the same applies here..).
Maybe we should take a step back and add those converters (which don't depend on any JPA APIs at all) to the DefaultConversionService in Spring Framework core - this whould eliminate the problem in the first place, right? (Actually that seems to be (partially) the case already SPR-11259.