BAEL-6320: added code support for the @NaturalId article

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/Application.java

@@ -0,0 +1,14 @@
+package com.baeldung.spring.data.jpa.naturalid;
+
+import com.baeldung.spring.data.jpa.naturalid.repository.NaturalIdRepositoryImpl;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+
+@SpringBootApplication
+public class Application {
+
+    public static void main(String[] args) {
+        SpringApplication.run(SpringBootApplication.class, args);
+    }
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/HotelRoomsService.java

@@ -0,0 +1,35 @@
+package com.baeldung.spring.data.jpa.naturalid;
+
+import com.baeldung.spring.data.jpa.naturalid.entity.ConferenceRoom;
+import com.baeldung.spring.data.jpa.naturalid.entity.GuestRoom;
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.EntityManagerFactory;
+import org.hibernate.Session;
+import org.springframework.stereotype.Service;
+
+import java.util.Optional;
+
+@Service
+public class HotelRoomsService {
+
+	private final EntityManager entityManager;
+
+	public HotelRoomsService(EntityManagerFactory entityManagerFactory) {
+		this.entityManager = entityManagerFactory.createEntityManager();
+	}
+
+	public Optional<ConferenceRoom> conferenceRoom(String name) {
+		Session session = entityManager.unwrap(Session.class);
+		return session.bySimpleNaturalId(ConferenceRoom.class)
+		  .loadOptional(name);
+	}
+
+	public Optional<GuestRoom> guestRoom(int roomNumber, int floor) {
+		Session session = entityManager.unwrap(Session.class);
+		return session.byNaturalId(GuestRoom.class)
+		  .using("roomNumber", roomNumber)
+		  .using("floor", floor)
+		  .loadOptional();
+	}
+
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/NaturalIdRepoConfig.java

@@ -0,0 +1,10 @@
+package com.baeldung.spring.data.jpa.naturalid;
+
+import com.baeldung.spring.data.jpa.naturalid.repository.NaturalIdRepositoryImpl;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+
+@Configuration
+@EnableJpaRepositories(repositoryBaseClass = NaturalIdRepositoryImpl.class)
+public class NaturalIdRepoConfig {
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/entity/ConferenceRoom.java

@@ -0,0 +1,56 @@
+package com.baeldung.spring.data.jpa.naturalid.entity;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import org.hibernate.annotations.NaturalId;
+
+@Entity
+public class ConferenceRoom {
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@NaturalId(mutable = true)
+	private String name;
+
+	private int capacity;
+
+	public ConferenceRoom(String name, int capacity) {
+		this.name = name;
+		this.capacity = capacity;
+	}
+
+	protected ConferenceRoom() {
+	}
+
+	public Long getId() {
+		return id;
+	}
+
+	public void setId(Long id) {
+		this.id = id;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public int getCapacity() {
+		return capacity;
+	}
+
+	public void setCapacity(int capacity) {
+		this.capacity = capacity;
+	}
+
+	@Override
+	public String toString() {
+		return "HotelRoom{" +
+				"id=" + id +
+				", name='" + name + '\'' +
+				", capacity=" + capacity +
+				'}';
+	}
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/entity/GuestRoom.java

@@ -0,0 +1,73 @@
+package com.baeldung.spring.data.jpa.naturalid.entity;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import org.hibernate.annotations.NaturalId;
+
+@Entity
+public class GuestRoom {
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@NaturalId
+	private Integer roomNumber;
+
+	@NaturalId
+	private Integer floor;
+
+	private String name;
+	private int capacity;
+
+
+	public GuestRoom(int roomNumber, int floor, String name, int capacity) {
+		this.roomNumber = roomNumber;
+		this.floor = floor;
+		this.name = name;
+		this.capacity = capacity;
+	}
+
+	protected GuestRoom() {
+	}
+
+	public Long getId() {
+		return id;
+	}
+
+	public Integer getRoomNumber() {
+		return roomNumber;
+	}
+
+	public Integer getFloor() {
+		return floor;
+	}
+
+	public int getCapacity() {
+		return capacity;
+	}
+
+	public void setCapacity(int capacity) {
+		this.capacity = capacity;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	@Override
+	public String toString() {
+		return "GuestRoom{" +
+				"id=" + id +
+				", roomNumber=" + roomNumber +
+				", floor=" + floor +
+				", name=" + name +
+				", capacity=" + capacity +
+				'}';
+	}
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/repository/ConferenceRoomJpaRepo.java

@@ -0,0 +1,9 @@
+package com.baeldung.spring.data.jpa.naturalid.repository;
+
+import com.baeldung.spring.data.jpa.naturalid.entity.ConferenceRoom;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface ConferenceRoomJpaRepo extends JpaRepository<ConferenceRoom, Long> {
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/repository/ConferenceRoomRepository.java

@@ -0,0 +1,8 @@
+package com.baeldung.spring.data.jpa.naturalid.repository;
+
+import com.baeldung.spring.data.jpa.naturalid.entity.ConferenceRoom;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface ConferenceRoomRepository extends NaturalIdRepository<ConferenceRoom, String> {
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/repository/GuestRoomJpaRepo.java

@@ -0,0 +1,9 @@
+package com.baeldung.spring.data.jpa.naturalid.repository;
+
+import com.baeldung.spring.data.jpa.naturalid.entity.GuestRoom;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface GuestRoomJpaRepo extends JpaRepository<GuestRoom, Long> {
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/repository/NaturalIdRepository.java

@@ -0,0 +1,11 @@
+package com.baeldung.spring.data.jpa.naturalid.repository;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.repository.NoRepositoryBean;
+
+import java.util.Optional;
+
+@NoRepositoryBean
+public interface NaturalIdRepository<T, ID>  extends JpaRepository<T, ID> {
+	Optional<T> naturalId(ID naturalId);
+}

persistence-modules/spring-data-jpa-repo-3/src/main/java/com/baeldung/spring/data/jpa/naturalid/repository/NaturalIdRepositoryImpl.java

@@ -0,0 +1,28 @@
+package com.baeldung.spring.data.jpa.naturalid.repository;
+
+import jakarta.persistence.EntityManager;
+import org.hibernate.Session;
+import org.springframework.data.jpa.repository.support.JpaEntityInformation;
+import org.springframework.data.jpa.repository.support.SimpleJpaRepository;
+import org.springframework.data.repository.NoRepositoryBean;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.io.Serializable;
+import java.util.Optional;
+
+public class NaturalIdRepositoryImpl<T, ID extends Serializable> extends SimpleJpaRepository<T, ID> implements NaturalIdRepository<T, ID> {
+	private final EntityManager entityManager;
+
+	public NaturalIdRepositoryImpl(JpaEntityInformation<T, ?> entityInformation, EntityManager entityManager) {
+		super(entityInformation, entityManager);
+		this.entityManager = entityManager;
+	}
+
+	@Override
+	public Optional<T> naturalId(ID naturalId) {
+		return entityManager.unwrap(Session.class)
+		  .bySimpleNaturalId(this.getDomainClass())
+		  .loadOptional(naturalId);
+	}
+
+}

persistence-modules/spring-data-jpa-repo-3/src/main/resources/application.properties

@@ -1 +1,2 @@
-
+logging.level.org.hibernate.SQL=DEBUG
+logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE

persistence-modules/spring-data-jpa-repo-3/src/test/java/com/baeldung/spring/data/jpa/naturalid/NaturalIdIntegrationTest.java

@@ -0,0 +1,61 @@
+package com.baeldung.spring.data.jpa.naturalid;
+
+import com.baeldung.spring.data.jpa.naturalid.entity.ConferenceRoom;
+import com.baeldung.spring.data.jpa.naturalid.entity.GuestRoom;
+import com.baeldung.spring.data.jpa.naturalid.repository.ConferenceRoomJpaRepo;
+import com.baeldung.spring.data.jpa.naturalid.repository.ConferenceRoomRepository;
+import com.baeldung.spring.data.jpa.naturalid.repository.GuestRoomJpaRepo;
+import jakarta.transaction.Transactional;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.annotation.Rollback;
+
+import java.util.Optional;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest
+class NaturalIdIntegrationTest {
+
+	@Autowired
+	private HotelRoomsService service;
+
+	@Autowired
+	private GuestRoomJpaRepo guestRoomJpaRepo;
+	@Autowired
+	private ConferenceRoomJpaRepo conferenceRoomJpaRepo;
+
+	@Autowired
+	private ConferenceRoomRepository conferenceRoomRepository;
+
+	@Test
+	void whenWeFindByNaturalKey_thenEntityIsReturnedCorrectly() {
+		guestRoomJpaRepo.save(new GuestRoom(23, 3, "B-423", 4));
+
+		Optional<GuestRoom> result = service.guestRoom(23, 3);
+
+		assertThat(result).isPresent()
+		  .hasValueSatisfying(room -> "B-423".equals(room.getName()));
+	}
+
+	@Test
+	void whenWeFindBySimpleNaturalKey_thenEntityIsReturnedCorrectly() {
+		conferenceRoomJpaRepo.save(new ConferenceRoom("Colorado", 100));
+
+		Optional<ConferenceRoom> result = service.conferenceRoom("Colorado");
+
+		assertThat(result).isPresent()
+		  .hasValueSatisfying(room -> "Colorado".equals(room.getName()));
+	}
+
+	@Test
+	void givenNaturalIdRepo_whenWeFindBySimpleNaturalKey_thenEntityIsReturnedCorrectly() {
+		conferenceRoomJpaRepo.save(new ConferenceRoom("Nevada", 200));
+
+		Optional<ConferenceRoom> result = conferenceRoomRepository.naturalId("Nevada");
+
+		assertThat(result).isPresent()
+		  .hasValueSatisfying(room -> "Nevada".equals(room.getName()));
+	}
+}