Spring Data JPA Repository Pattern (MVC)

Example

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface UserRepository extends JpaRepository<User, Long> {
    // Custom query methods
    Optional<User> findByEmail(String email);
}

Guidelines

• Extend JpaRepository<Entity, ID> for standard CRUD and pagination.
• Use method naming conventions for custom queries (e.g., findBy...).
• Use @Query for custom JPQL/SQL if needed.
• Return Optional<T> for single results, List<T> for collections.
• Avoid business logic in repositories; keep them focused on data access.
• Annotate with @Repository (optional with Spring Boot, but recommended for clarity).

References

• Spring Data JPA Reference
• Spring Guides: Accessing Data with JPA