Jackson Mapper没有反序列化JSON – (无法读取JSON：已经有了id(java.lang.Integer)的POJO)

在将json发布到Spring Controller时获得上述异常.看来Jackson Mapper无法反序列化json. CategoryDTO注释为：

@JsonIdentityInfo(generator=ObjectIdGenerators.IntSequenceGenerator.class,property="@id",scope = CategoryDTO.class)

JSON：

[
   {
      "categories":[
         {
            "@id":27048,"name":"Sportbeha's","description":null,"parent":{
               "@id":22416,"name":"Fitness","parent":{
                  "@id":21727,"name":"Collectie","description":null
               }
            }
         },{
            "@id":27050,"parent":{
               "@id":24474,"name":"Voetbal","parent":21727
            }
         }
      ]
   },{
      "categories":[
         {
            "@id":27048,"parent":21727
            }
         }
      ]
   }
]

Java代码：

@Jsonserialize(include= Jsonserialize.Inclusion.NON_NULL)
@JsonIdentityInfo(generator=ObjectIdGenerators.IntSequenceGenerator.class,scope = CategoryDTO.class)
@JsonIgnoreProperties(ignoreUnkNown = truE)
public class CategoryDTO implements serializable{

    private Long id;
    private String name;
    private String description;
    private CategoryDTO parent;

    @JsonIgnore
    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String Name) {
        this.name = name;
    }


    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public CategoryDTO getParent() {
        return parent;
    }

    public void setParent(CategoryDTO parent) {
        this.parent = parent;
    }

}


**Spring Controller :** 

    @requestMapping(value = "/categories",method = requestMethod.POST,consumes =  "application/json;charset=UTF-8",produces = "application/json;charset=UTF-8")
    public ResponseEntity<>

问题似乎与这片json有关：

"parent":{
    "@id":21727,"description":null
}

它存在于数组中的两个对象中.