使用SpringDataJpa创建中间表

//fetch=FetchType.EAGER 关闭懒加载 相当于hibernate中的lazy=false
	//joinColumns 配置中间表的主列
	//inverseJoinColumns=@JoinColumn(name="t_roleId") 创建中间表的副列
	@ManyToMany(fetch=FetchType.EAGER)
	@JoinTable(name="t1_user_permission",joinColumns=@JoinColumn(name="t_userId"),
	inverseJoinColumns=@JoinColumn(name="t_perId"))
	private List<Permission> perList;
 
//mappedBy="roleList" 变成双向
	//mappedBy="roleList" 把主权交给user 然后 role里面就不创建中间表了
	//表示声明自己不是多对多的关系维护端，由对方来维护
	@ManyToMany(mappedBy="perList",fetch=FetchType.EAGER)
	private List<User> userList;

CREATE TABLE `mb_member_dept` (
    `member_id`  bigint(20) NOT NULL ,
    `dept_id`  bigint(20) NOT NULL ,
    PRIMARY KEY (`member_id`, `dept_id`)
)
ENGINE=InnoDB
DEFAULT CHARACTER SET=utf8mb4 COLLATE=utf8mb4_general_ci
ROW_FORMAT=DYNAMIC;

/**
* 用户部门实体
* @author lizebin
* @version 1.0
* @date 2021/2/18 12:48 上午
*
**/
@Getter
@Setter
@Entity
@Table(name = "mb_member_dept")
public class MemberDeptPO implements Serializable{
  private static final long serialVersionUID = 1271571231859316736L;
  /**
  * 联合主键用户ID
  */
  @Column(name = "member_id", length = 20)
  private long memberId;
  /**
  * 联合主键部门ID
  */
  @Column(name = "dept_id", length = 20)
  private long deptId;
}

/**
* 用户部门关系联合主键定义
* @author lizebin
* @version 1.0
* @date 2021/2/18 10:36 上午
*
**/
@Getter
@Setter
public class MemberDeptKey implements Serializable {
    private static final long serialVersionUID = -5482200454871393530L;
	/**联合主键，字段名称与MemberDeptPO 类中一致*/
    private long memberId;
	/**联合主键，字段名称与MemberDeptPO 类中一致*/
    private long deptId;
    public MemberDeptKey() { }
    public MemberDeptKey(long memberId, long deptId) {
        this.memberId = memberId;
        this.deptId = deptId;
    }
}

/**
* 用户部门实体
* @author lizebin
* @version 1.0
* @date 2021/2/18 12:48 上午
*
**/
@Getter
@Setter
@Entity
@Table(name = "mb_member_dept")
@IdClass(value = MemberDeptKey.class) // 定义联合主键类
public class MemberDeptPO implements Serializable{
  private static final long serialVersionUID = 1271571231859316736L;
  /**
  * 联合主键用户ID
  */
  @Id // 定义该字段为主键
  @Column(name = "member_id", length = 20)
  private long memberId;
  /**
  * 联合主键部门ID
  */
  @Id // 定义该字段为主键
  @Column(name = "dept_id", length = 20)
  private long deptId;
}

@Repository
public interface IMemberDeptRepository extends JpaRepository<T, ID>, JpaSpecificationExecutor<T> {
}

@Repository
public interface IMemberDeptRepository extends JpaRepository<MemberDeptPO, MemberDeptKey>, JpaSpecificationExecutor<MemberDeptPO> {
    /**通过ID获取数据信息*/
    MemberDeptPO findById(MemberDeptKey id);
}

@Autowired
private IMemberDeptRepository memberDeptRepository;
MemberDeptPO memberDeptPO = memberDeptRepository.findById(new MemberDeptKey(1l, 0l));