JpaRepository vs CRUDRepository findAll

JpaRepository extends PagingAndSortingRepository

and PagingAndSortingRepository extends CrudRepository.

This allows JpaRepository to have a more specific return type of Itrable which is List

The class CrudRepository is part of the Spring Data Commons project and is the recommended interface to extend regardless of the actual data store used.

The reason CrudRepository methods return Iterable and not List (or Set) is because some data stores allow streaming of results and using a Collection type would result in loss of functionality for such stores.