Hibernate: Find entity from one to many table - spring

Question

I have two tables
CREATE TABLE `heroic_quality`
(
`id` INT NOT NULL AUTO_INCREMENT,
`name` VARCHAR(515) NOT NULL UNIQUE,
PRIMARY KEY (`id`)
);
CREATE TABLE `hero`
(
`id` INT NOT NULL AUTO_INCREMENT,
`name` VARCHAR(515) NOT NULL UNIQUE,
`quality_id` INT DEFAULT NULL,
FOREIGN KEY (`quality_id`) REFERENCES heroic_quality (id),
PRIMARY KEY (`id`)
);
And the objects in hibernate are
#Table(name = "heroic_quality")
#Entity(name = "heroic_quality")
public class HeroicQuality
{
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id")
protected long id;
#Column(name = "name", nullable = false, unique = true)
private String name;
#OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
#JoinColumn(name = "id")
#Fetch(FetchMode.SELECT)
private List<Hero> heroes;
//ommited getters and setters for shortness
}
#Table(name = "hero")
#Entity(name = "hero")
public class Hero
{
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id")
protected long id;
#Column(name = "name", nullable = false, unique = true)
private String name;
//ommited getters and setters for shortness
}
As you see my Hero class doesn't have reference to heroic quality, and I would like to keep it that way.
Also I have a repository
#Repository
public interface HeroicQualityDAO
extends PagingAndSortingRepository<HeroicQuality, Long>
{
Optional<HeroicQuality> findByName(String name);
List<HeroicQuality> findByOrderByIdDesc();
}
What I would like to do is have a method such as
Optional<HeroicQuality> findByHeroName(String heroName)
Such that if given a name of hero from Hero table I will be able to get heroic quality object.
How can I make such a method?
Is there any way I can get heroic quality object without having a reference to it in the hero object?
How can I go about doing that?

Answer 1

Add the following method to HeroicQualityDAO.
Optional<HeroicQuality> findByHeroesName(String heroName);
If you are not happy with the method name, you can do
#Query("Select h from HeroicQuality hq join hq.heros h where h.name = :name")
Optional<HeroicQuality> findByHeroName(String name);