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.
最佳答案
@H_301_37@如果对每个嵌套对象使用相同的CategoryDto,
"parent": 21727
因为杰克逊期待一个对象,所以不会反序列化.要仅使用id反序列化父CategoryDto,您需要POST以下JSON：
"parent": {
"@id": 21727
}
