using List<Map<String, Object>> as return type for hql queries

HibernateSelectMapApplication.java

package test;

import java.util.List;
import java.util.Map;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@EnableJpaRepositories
@SpringBootApplication
public class HibernateSelectMapApplication implements CommandLineRunner {

	private StudentRepo studentRepo;

	public HibernateSelectMapApplication(StudentRepo studentRepo) {
		this.studentRepo = studentRepo;
	}

	public static void main(String[] args) {
		SpringApplication.run(HibernateSelectMapApplication.class, args);
	}

	@Override
	public void run(String... args) throws Exception {
		Student s1 = new Student(null, "Boody", "Abdullah", 2, "Egypt");
		Student s2 = new Student(null, "Farida", "Abdullah", 2, "Egypt");

		studentRepo.save(s1);
		studentRepo.save(s2);

		Iterable<Student> findAll = studentRepo.findAll();
		System.out.println(findAll);

		List<Map<String, Object>> map = studentRepo.findFirstLastNamesAndGrade();
		System.out.println(map);
	}
}

@Repository
interface StudentRepo extends CrudRepository<Student, Long> {

	@Query("select new map (o.firstName as firstName, o.lastName as lastName, o.grade as grade) from Student o")
	List<Map<String, Object>> findFirstLastNamesAndGrade();
}

@Data
@Table
@Entity
@NoArgsConstructor
@AllArgsConstructor
class Student {
	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	Long id;
	String firstName;
	String lastName;
	Integer grade;
	String country;
}