JPA @ManyToMany关系

import javax.persistence.*;
import java.util.Set;

@Entity
public class Student {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String name;

    @ManyToMany
    @JoinTable(
        name = "student_course",
        joinColumns = @JoinColumn(name = "student_id"),
        inverseJoinColumns = @JoinColumn(name = "course_id")
    )
    private Set<Course> courses;

    // Getters and Setters
}

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

    private String title;

    @ManyToMany(mappedBy = "courses")
    private Set<Student> students;

    // Getters and Setters
}

@Entity
public class Student {
    @ManyToMany
    @BatchSize(size = 10)
    private Set<Course> courses;
}

@ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE})
private Set<Course> courses;