java - 在JPA中创建表之间的关系

Question

我有主 table 商户和副 table 终端:

商户表:

@Entity
@Table
public class Merchants {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id", updatable = false, nullable = false)
    private int id;

    @Column
    private String name;

    @Column
    private String login;
}

终端表:

@Entity
@Table
public class Terminals {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id", updatable = false, nullable = false)
    private int id;

    @Column
    private int merchant_id;

    @Column
    private String mode;
}

我想将merchant_id设置到表Terminals中。我想多对多将是适当的关系。我怎样才能创建它？

Answer 1

如果您有连接表:

在商人类别上:

 @ManyToMany
 @JoinTable(name="MER_TER", joinColumns=@JoinColumn(name="MERCH_ID", referencedColumnName="id"),
  inverseJoinColumns=@JoinColumn(name="TERM_ID", referencedColumnName="id"))
  private List<Terminals> terminalsList;

在终端类上:

@ManyToMany(mappedBy="terminalsList")
private List<Merchants> merchantsList;

引用页:link

如果您没有连接表，请尝试查看此处:https://stackoverflow.com/a/25018992