某学生管理系统的3个表设计如下，并且已经在数据库中存在。

学生表:

课程表

关联表:

@Data
@Entity
@Table(name="student")
@JsonIgnoreProperties(value={"hibernateLazyInitializer"})
public class Student implements Serializable {
	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private Integer id;

	@Column(nullable=false,length=16)
	private String sid;

	private String sname;

	private String sex;

	private int  classId;

	@ManyToMany
	@JoinTable(
			name="stu_cour",   //中间表的名称
			joinColumns = @JoinColumn(name="stu_id"),//中间表stu_cour字段关联student表的主键字段stu_id
			inverseJoinColumns = @JoinColumn(name="cour_id")//中间表stu_cour字段关联cour表的主键字段cour_id

	)
	@JsonIgnore
	private Set<Course> course;
}

@Data
@Entity
@Table(name="course")
@JsonIgnoreProperties(value={"hibernateLazyInitializer"})
public class Course implements Serializable {

	@Id
	@GeneratedValue(strategy = GenerationType.IDENTITY)
	private Integer id;

	private String cname;

	private int tutorId;

	private String semester;

	@ManyToMany(mappedBy= "courses")  //表示该表为从表，关系由对方维护
	@JsonIgnore
	private Set<Student> students;
}