Question

我遇到了一个问题，我需要一个可以在多个公司中注册的用户。这些公司可以注册多个产品。用户应该知道他拥有哪些公司的产品。

到目前为止，这是我的解决方案，但是无法正确返回角色：

class User {
  @Id
  @Column(name = "USER_ID")
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Long id;

  @Column(name = "USERNAME", unique = true)
  private String username;

  @Column(name = "PASSWORD")
  private String password;

  @ManyToMany(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
  @JoinTable(name = "USER_ROLES",
        joinColumns = {@JoinColumn(name = "USER_ID"), @JoinColumn(name = "COMPANY_ID"), @JoinColumn(name="PRODUCT_ID")},
        inverseJoinColumns = {@JoinColumn(name = "ROLE_ID"), @JoinColumn(name = "COMPANY_ID"), @JoinColumn(name="PRODUCT_ID")})
  private Set<Role> roles = new HashSet<>();

  @ManyToMany(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
  @JoinTable(name = "USER_COMPANIES",
        joinColumns = {@JoinColumn(name = "USER_ID")},
        inverseJoinColumns = {@JoinColumn(name = "COMPANY_ID")})
  private Set<Company> companies = new HashSet<>();
}

class Role {
  @Id
  @Column(name = "ROLE_ID")
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Long id;

  @Column(name = "ROLE_NAME")
  @Enumerated(EnumType.STRING)
  @NaturalId
  private RoleName role;

  @ManyToMany(mappedBy = "roles", fetch = FetchType.LAZY)
  @JsonIgnore
  private Set<User> userList = new HashSet<>();
}

class Company {
  @Id
  @Column(name = "COMPANY_ID")
  private Long id;

  @ManyToMany(mappedBy = "companies", fetch = FetchType.LAZY)
  @JsonIgnore
  private Set<User> userList = new HashSet<>();

  @OneToMany(mappedBy = "company")
  private Set<Product> products;
}

class Product {
  @Id
  @Column(name = "COMPANY_ID")
  private Long id;

  @ManyToOne
  @JoinColumn(name="COMPANY_ID", nullable=false)
  private Company company;

  private ProductType productType;

}

我的最终目标是从用户那里获得角色，任何人都可以帮忙吗？提前非常感谢！

Answer 1

     @ManyToMany(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE}) 
     @JoinTable(name = "USER_ROLES", joinColumns = {@JoinColumn(name = "USER_ID"), 
     @JoinColumn(name = "COMPANY_ID"), @JoinColumn(name="PRODUCT_ID")}, inverseJoinColumns = 
    {@JoinColumn(name = "ROLE_ID"), @JoinColumn(name = "COMPANY_ID"), 
     @JoinColumn(name="PRODUCT_ID")}) 
     ***@JsonBackReference***
     private Set<Role> roles = new HashSet<>();

尝试使用pojo用户中的@ JsonBackReference。@ JsonBackReference将在反序列化过程中为用户设置角色。

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1 个答案: