Custom generic spring data repository

Question

Using spring data, I have two tables that shares the same structure. The two tables are represented by two different entities, that inherit from the same class :

@MappedSuperclass
public abstract class SuperEntity<T extends SuperEntity> {
// ...
}
@Table(name = "FOO")
@Entity
public class Foo extends SuperEntity<Foo> {
// ...
}
@Table(name = "BAR")
@Entity
public class Bar extends SuperEntity<Bar> {
// ...
}

I also have a generic repository, that I would like to use to factorize to requesting logic, and two sub-repository : one for each table.

public interface GenericEvtRepository <T extends SuperEntity<?>> extends JpaRepository<T, String> { }
public interface FooRepository extends GenericEvtRepository<Foo> {}
public interface BarRepository extends GenericEvtRepository<Bar> {}

I would like to add an actual query implementation to this repository (i.e. using EntityManager / Criteria). Therefore I tried to adapt the custom repository strategy to my generic case

@Repository
public class GenericEvtRepositoryImpl<T extends SuperEntity<?>> extends SimpleJpaRepository<T, String> implements GenericEvtRepository<T> {
 @PersistenceContext
 EntityManager entityManager;
 // Some logic using entityManager
 public SuperEntity myCustomRequest() { /*...*/ }
}

However my application doesn't start, with the exception :

org.springframework.data.mapping.PropertyReferenceException: No property myCustomRequest found for type Foo!

Not sure what I'm doing wrong, but Spring seems to think that myCustomRequest is an attribute from my entities, instead of a method.

I'm using spring-boot 1.5.6 and spring-data-jpa 1.11.6.

Minimal reproductible exemple

Answer 1

Luckily I was able to reproduce your issue,

How spring recommends custom repository implementation is specified here in spring docs.

So, you can do something like below,

public interface CustomEntityRepository<T extends SuperTag<?>>
public interface FooRepository extends JpaRepository<Foo, Integer>, CustomEntityRepository<Foo>
public interface BarRepository extends JpaRepository<Bar, Integer>, CustomEntityRepository<Bar>

And define common implementation for CustomEntityRepository<T extends SuperTag<?>> as below,

@Repository
// NOTE: Implementation name must follow convension as InterfaceName + 'Impl'
public class CustomEntityRepositoryImpl<T extends SuperTag<?>> implements 
CustomEntityRepository<T> {
 @PersistenceContext
 private EntityManager entityManager;
 // Generic custom implementation here
}

Spring automatically detects implementation of Custom Interface CustomEntityRepository based on implementation class naming convention.

• Robert jardonneau: Thanks for your help, however after modifying my code to fit yours doesn't solve my problem. Would you have a working exemple ?
• Amit Patil: you can refer this github.com/iamitpatil1993/spring-data-jpa/commit/… Names are quite different, hope this help.
• Robert jardonneau: Thanks for your efforts, however I think that my issue is that I don't use the same version of spring-data-jpa. Here is a minial exemple : github.com/ptitFicus/spring-data-jpa-generic-custom-repository
• victor.chicu: As I noticed this problem occurs only when repo is generic.. Did you solve this problem?