Hibernate 我在jpa存储库中的多对多关系中遇到了问题，无法在联接表中使用引用进行保存

我有学生课

@Entity
public class Student {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @Column(name = "first_name")
    private String firstName;

    @ManyToMany(mappedBy = "students", fetch = FetchType.LAZY, cascade = {CascadeType.MERGE, CascadeType.DETACH, CascadeType.PERSIST, CascadeType.REFRESH})
    private List<Course> courses;

    public void addCourse(Course theCourse) {
        if (courses == null) {
            courses = new ArrayList<>();
        }
        courses.add(theCourse);
        theCourse.addStudents(this);
    }

}

现在我想创建学生和课程，并保存它们，将每个引用保存在联接表中。 我不知道先是哪一个，然后再加上另一个。

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有人可以帮助我并提供描述此主题的参考资料？

如果您想要多对多双向关系，您应该定义所属方。因此，如果选择课程作为拥有方，映射将如下所示：

public class Course {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String title;

    @ManyToMany(cascade = CascadeType.PERSIST)
    private List<Student> students = new ArraysList<>();
...

有关详细信息：

//definitely I wrote syntax wrong here because i don't copy and paste from code.
Course c =new Course(//fill constrouctor);
CourseRepositoryy.save(c);

student s = new Student(//fill constrouctor);
s.addCourse(c)
StudentRepository.save(s);

or

student s = new Student(//fill constrouctor);
Course c =new Course(//fill constrouctor);
c.addStudents(s);
save(s);
save(c);

public class Course {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String title;

    @ManyToMany(cascade = CascadeType.PERSIST)
    private List<Student> students = new ArraysList<>();
...