Java – how to map a set of string objects using JPA annotations?

@Entity

@Entity
public class TestClass implements Serializable{
    private Integer id;
    private Set<String> mySet;

    @Id
    @GeneratedValue
    public Integer getId() {
        return id;
    }
    @OneToMany(cascade={CascadeType.ALL})
    public Set<String> getMySet() {
        return mySet;
    }
}

I received the following error

Caused by: org.hibernate.AnnotationException: Use of @OneToMany or @ManyToMany targeting an unmapped class: TestClass.mySet[java.lang.String]

Or if I leave @ onetomany

org. hibernate. Mappingexception: unable to determine: Java util. Type of set in table: Test_ Class, for column: [org. Hibernate. Mapping. Column (my_sets)]

Solution

You'll find a pretty good answer here The rules for lists also apply to collections