Repository (marker) ├── CrudRepository<T, ID> ├── PagingAndSortingRepository<T, ID> └── JpaRepository<T, ID> (JPA-specific) 3.3 Query Derivation — The Magic Method name → JPQL query automatically.
3. Spring Data JPA Deep Dive 3.1 Configuration (Java Config) @Configuration @EnableJpaRepositories(basePackages = "com.example.repo") @EnableTransactionManagement public class JpaConfig @Bean public DataSource dataSource() /* HikariCP etc */ @Bean public LocalContainerEntityManagerFactoryBean entityManagerFactory() // JPA vendor adapter (Hibernate)
// In repo: List<UserSummary> findByLastName(String last); @DataJpaTest @AutoConfigureTestDatabase(replace = Replace.NONE) // use real DB if needed class UserRepoTest @Autowired private TestEntityManager entityManager; @Autowired private UserRepo repo; @Test void shouldFindByEmail() User user = new User("test@example.com"); entityManager.persist(user); Optional<User> found = repo.findByEmail("test@example.com"); assertThat(found).isPresent(); spring data spring data packt .pdf checked
@Query(" 'location' : $near : $geometry : type: 'Point', coordinates: ?0 , $maxDistance: ?1 ") List<Store> findNearby(double[] point, double maxDistance); 7. Spring Data REST – Instant Hypermedia API Add one dependency ( spring-boot-starter-data-rest ) → your repositories become REST endpoints.
interface UserRepo extends JpaRepository<User, Long> List<User> findByLastNameAndAgeGreaterThan(String lastName, int age); // Generates: where last_name = ?1 and age > ?2 Spring Data REST – Instant Hypermedia API Add
Example:
@CreatedBy private String createdBy;
And , Or , Between , LessThan , GreaterThan , Like , Containing , OrderBy , First , Top , AllIgnoreCase , Exists . 3.4 @Query — Explicit control @Query("SELECT u FROM User u WHERE u.email = :email") User findByEmail(@Param("email") String email); // Native SQL @Query(value = "SELECT * FROM users u WHERE u.status = 1", nativeQuery = true) List<User> findAllActive(); 3.5 Modifying queries + transactions @Modifying @Transactional @Query("UPDATE User u SET u.active = false WHERE u.lastLogin < :date") int deactivateInactiveUsers(@Param("date") LocalDate date); 4. Auditing – Automatic Timestamps @Entity public class User @CreatedDate private LocalDateTime createdAt; @LastModifiedDate private LocalDateTime updatedAt;