Question

我在杰克逊序列化方面遇到了一个奇怪的问题 - 我有一个Role实体有一个嵌套的Permission entity，而后者又包含一个嵌套的Metadata实体。当这些实体作为列表从Spring MVC @RestController中检索时，Jackson将Permission集合序列化为JSON数组。问题是有时放在这个数组中的元素只是Permission的id而不是对象的序列化表示。

Role.class：

@Entity
@Table(name = "t_db_roles")
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class,     property = "id", scope = Role.class)
  public class Role implements GrantedAuthority {

  private final static Logger log = LoggerFactory.getLogger(Permission.class);

  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  @Column(name = "auto_id")
  private int id;

  @Column(name = "role", length = 50)
  private String name;

  @OneToMany(fetch = FetchType.EAGER)
  @JoinTable(name = "t_db_role_permissions",
        joinColumns = {@JoinColumn(name = "roleid", referencedColumnName = "auto_id")},
        inverseJoinColumns = {@JoinColumn(name = "permid", referencedColumnName = "auto_id")}
  )
  private Set<Permission> permissions;

  // getters and setters omitted

}

Permission.class：

@Entity
@Table(name = "t_db_permissions")
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id", scope = Permission.class)
public class Permission implements GrantedAuthority {

    private final static Logger log = LoggerFactory.getLogger(Permission.class);

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "auto_id")
    private int id;

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

    @OneToOne(mappedBy = "permission")
    private Metadata metadata;

}

Metadata.class

@Entity
@Table(name = "t_report_data")
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id", scope = Metadata.class)
public class Metadata {

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

    @Column(name = "file_name")
    private String fileName;

    @Column(name = "human_name")
    private String humanName;

    @Column(name = "links_to")
    @JsonIgnore
    private Integer linksTo;

    @Column(name = "is_subreport")
    @JsonIgnore
    private Boolean isSubreport;

    @OneToOne(cascade = javax.persistence.CascadeType.ALL, fetch = FetchType.EAGER, optional = false)
    @JoinColumn(name = "permid")
    private Permission permission;
}

控制器：

@RestController
public class RoleRestController {

    private final static Logger log = LoggerFactory.getLogger(PermissionRestController.class);
    private RoleService roleService;
    private MetadataService metadataService;

    @Autowired
    public void setRoleService(RoleService service) {
        this.roleService = service;
    }

    @Autowired
    public void setMetadataService(ReportMetadataService service) { this.metadataService = service; }

    @RequestMapping(value = "/admin/roles/", method = RequestMethod.GET)
    public List<Role> getRoles() {
        return roleService.getRoles();
    }
}

我很确定问题出现在序列化中 - 回显List<Role>到控制台按预期工作，但这里是JSON返回（注意权限数组的第一个元素是整数而不是而不是JSON对象）：

{
    "id": 10,
    "name": "ROLE_TESTER",
    "permissions": [
        14,
        {
            "id": 7,
            "name": "ViewDailySettlementSummaryGL",
            "metadata": {
                "id": 41,
                "fileName": "acct_summary_gl.rptdesign",
                "humanName": "Daily Settlement Summary GL",
                "permission": 7
            },
            "authority": "ViewDailySettlementSummaryGL"
        },
        {
            "id": 6,
            "name": "ViewDailySettlementSummary",
            "metadata": {
                "id": 24,
                "fileName": "acct_summary_os.rptdesign",
                "humanName": "Daily Settlement Summary",
                "permission": 6
            },
            "authority": "ViewDailySettlementSummary"
        }
    ],
    "authority": "ROLE_TESTER"
}

我可以通过手动处理Role序列化来解决这个问题，但由于SpringMVC / Jackson序列化适用于项目中的其他类，因此我觉得这些类中一定存在问题。有什么想法吗？

Spring MVC / Jackson - 嵌套实体反序列化怪异

0 个答案: