java反序列化和名为“defaultReference”的多个反向引用属性

Question

我试图使用Jackson 1.9将嵌套JSON对象反序列化到POJO中，但遇到了麻烦。下面是我试图解析的类和示例JSON字符串

（省略了getter和setter）

JSON字符串：

sellerJson = "[{\"id\":\"1\",\"first_name\":\"Joe\",\"last_name\":\"Sellerman\",\"company\":\"NY CANYON RANCH\"," +
                    "\"prorated_sellers\":[{\"first_name\":\"Steve\",\"last_name\":\"Jobs\",\"company\":\"NY CANYON RANCH\"}," +
                    "{\"first_name\":\"Lorne\",\"last_name\":\"Michaels\",\"company\":\"NY CANYON RANCH\"}]," +
                    "\"pens\":[{\"id\":\"2\",\"pen_no\":\"902\"}]}]";

Java类：

@Table(name="seller")
public class SellerModel implements Serializable, Comparable<SellerModel> {

    private static final long serialVersionUID = 201302111531L;

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

    @Column()
    private String first_name;

    @Column()
    private String last_name;

    @Column()
    private String company;

    @Column()
    private Boolean is_prorated;

    @JsonIgnore
    @ManyToOne()
    @JoinColumn(name="parent_seller_id", referencedColumnName="id")
    private SellerModel parent_seller;

    @JsonManagedReference(value="seller-prorated")
    @OneToMany(mappedBy = "parent_seller", cascade={CascadeType.ALL}, orphanRemoval=true)
    private List<SellerModel> prorated_sellers;

    @JsonManagedReference(value="seller-pen")
    @OneToMany(mappedBy = "parent_seller", cascade={CascadeType.ALL}, orphanRemoval=true)
    private List<PenModel> pens;
}

@Table(name="pen")
public class PenModel implements Serializable, Comparable<PenModel> {

    private static final long serialVersionUID = 201302111537L;

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

    @Column()
    private String pen_no;

    @JsonBackReference(value="pen-seller")
    @ManyToOne()
    @JoinColumn(name="parent_seller_id", referencedColumnName="id")
    private SellerModel parent_seller;

    @JsonManagedReference(value="pen-livestock")
    @OneToMany(mappedBy = "parent_pen", cascade={CascadeType.ALL}, orphanRemoval=true)
    private List<LivestockModel> livestock;
}

但是，当我尝试执行反序列化时：

List<SellerModel> sellers = (List<SellerModel>) mapper.readValue(sellerJson, 
                    mapper.getTypeFactory().constructCollectionType(List.class, SellerModel.class));

我收到以下异常消息：

java.lang.IllegalArgumentException: Multiple back-reference properties with name 'defaultReference'

我读到提供（value='something-unique'）注释属性应该可以解决这个问题，但我没有任何运气。有人有什么建议吗

Answer 1

我至少看到两个问题。 首先：

• SellerModel.prorated_sellers注释为@JsonManagedReference(value="seller-pen")
• PenModel.parent_seller注释为@JsonBackReference(value="pen-seller")

他们必须同名，才能有关联

第二：

• SellerModel.parent_seller应该用@JsonManagedReference(value="seller-prorated")（管理的）注释，并删除@JsonIgnore注释
• SellerModel.prorated_sellers应该用@JsonBackReference(value="seller-prorated")（Back注释）