implementation (#17025)

Co-authored-by: technoddy <[email protected]>

Author: imsurajmishra

persistence-modules/spring-data-jpa-simple/src/main/java/com/baeldung/jpa/projection/model/Person.java

@@ -1,10 +1,18 @@
 package com.baeldung.jpa.projection.model;
 
+import com.baeldung.jpa.projection.view.PersonDto;
+
+import jakarta.persistence.ColumnResult;
+import jakarta.persistence.ConstructorResult;
 import jakarta.persistence.Entity;
 import jakarta.persistence.Id;
+import jakarta.persistence.NamedNativeQuery;
 import jakarta.persistence.OneToOne;
+import jakarta.persistence.SqlResultSetMapping;
 
 @Entity
+@NamedNativeQuery(name = "person_native_query_dto", query = "SELECT p.first_name, p.last_name From Person p where p.first_name LIKE :firstNameLike", resultSetMapping = "person_query_dto")
+@SqlResultSetMapping(name = "person_query_dto", classes = @ConstructorResult(targetClass = PersonDto.class, columns = { @ColumnResult(name = "first_name", type = String.class), @ColumnResult(name = "last_name", type = String.class), }))
 public class Person {
     @Id
     private Long id;

persistence-modules/spring-data-jpa-simple/src/main/java/com/baeldung/jpa/projection/repository/PersonRepository.java

@@ -1,6 +1,10 @@
 package com.baeldung.jpa.projection.repository;
 
+import java.util.List;
+
+import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.Repository;
+import org.springframework.data.repository.query.Param;
 
 import com.baeldung.jpa.projection.model.Person;
 import com.baeldung.jpa.projection.view.PersonDto;
@@ -12,4 +16,7 @@ public interface PersonRepository extends Repository<Person, Long> {
     PersonDto findByFirstName(String firstName);
 
     <T> T findByLastName(String lastName, Class<T> type);
+
+    @Query(name = "person_native_query_dto", nativeQuery = true)
+    List<PersonDto> findByFirstNameLike(@Param("firstNameLike") String firstNameLike);
 }

persistence-modules/spring-data-jpa-simple/src/main/java/com/baeldung/jpa/projection/view/PersonDto.java

@@ -31,4 +31,9 @@ public boolean equals(Object o) {
     public int hashCode() {
         return Objects.hash(firstName, lastName);
     }
+
+    @Override
+    public String toString() {
+        return "PersonDto{" + "firstName='" + firstName + '\'' + ", lastName='" + lastName + '\'' + '}';
+    }
 }

persistence-modules/spring-data-jpa-simple/src/test/java/com/baeldung/jpa/projection/JpaProjectionIntegrationTest.java

@@ -3,6 +3,9 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.springframework.test.context.jdbc.Sql.ExecutionPhase.AFTER_TEST_METHOD;
 
+import java.util.Arrays;
+import java.util.List;
+
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.AutoConfigurationPackage;
@@ -43,6 +46,13 @@ void whenUsingOpenProjections_thenViewWithRequiredPropertiesIsReturned() {
         assertThat(personView.getFullName()).isEqualTo("John Doe");
     }
 
+    @Test
+    void whenUsingClassBasedProjectionsAndJPANativeQuery_thenDtoWithRequiredPropertiesIsReturned() {
+        List<PersonDto> personDtos = personRepository.findByFirstNameLike("Jo%");
+        assertThat(personDtos.size()).isEqualTo(2);
+        assertThat(personDtos).isEqualTo(Arrays.asList(new PersonDto("John", "Doe"), new PersonDto("Job", "Doe")));
+    }
+
     @Test
     void whenUsingClassBasedProjections_thenDtoWithRequiredPropertiesIsReturned() {
         PersonDto personDto = personRepository.findByFirstName("John");

persistence-modules/spring-data-jpa-simple/src/test/resources/projection-insert-data.sql

@@ -1,2 +1,3 @@
 INSERT INTO person(id,first_name,last_name) VALUES (1,'John','Doe');
+INSERT INTO person(id,first_name,last_name) VALUES (2,'Job','Doe');
 INSERT INTO address(id,person_id,state,city,street,zip_code) VALUES (1,1,'CA', 'Los Angeles', 'Standford Ave', '90001');