直接自引用导致循环超类问题JSON [英] Direct self-reference leading to cycle Superclass issue JSON
问题描述
我尝试了一些我在搜索时发现的东西,但没有任何帮助,或者我没有正确实现。
I have tried several things I found while searching but nothing helped or I did not implement it correctly.
错误我得到了
Direct self-reference leading to cycle (through reference chain: io.test.entity.bone.Special["appInstance"]->io.test.entity.platform.ApplicationInstance["appInstance"])
这两个都扩展了基础实体和基础(超类)它还有 appInstance
。
Both these extend the base entity and in the base (super class) it has an appInstance
as well.
基本实体看起来与此类似
Base entity looks similar to this
@MappedSuperclass
public abstract class BaseEntity implements Comparable, Serializable {
@ManyToOne
protected ApplicationInstance appInstance;
//getter & setter
}
申请实体看起来像这样
public class ApplicationInstance extends BaseEntity implements Serializable {
private List<User> users;
// some other properties (would all have the same base and application instance . User entity will look similar to the Special.)
}
特殊实体
@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "objectType")
@JsonIgnoreProperties({"createdBy", "appInstance", "lastUpdatedBy"})
public class Special extends BaseEntity implements Serializable {
@NotNull
@Column(nullable = false)
private String name;
@Column(length = Short.MAX_VALUE)
private String description;
@NotNull
@Column(nullable = false)
private Double price;
@OneToOne
private Attachment image;
@Enumerated(EnumType.STRING)
@ElementCollection(targetClass = SpecialTag.class)
@CollectionTable(name = "special_tags")
@Column(name = "specialtag")
private List<SpecialTag> specialTags;
@Temporal(TemporalType.TIME)
private Date specialStartTime;
@Temporal(TemporalType.TIME)
private Date specialEndTime;
@Enumerated(EnumType.STRING)
@ElementCollection(targetClass = WeekDay.class)
@CollectionTable(name = "available_week_days")
@Column(name = "weekday")
private List<WeekDay> availableWeekDays;
@OneToMany(mappedBy = "special", cascade = CascadeType.REFRESH)
private List<SpecialStatus> statuses;
@OneToMany(mappedBy = "special", cascade = CascadeType.REFRESH)
private List<SpecialReview> specialReviews;
@Transient
private Integer viewed;
private Boolean launched;
@OneToMany(mappedBy = "special")
private List<CampaignSpecial> specialCampaigns;
@Override
@JsonIgnore
public ApplicationInstance getAppInstance() {
return super.getAppInstance();
}
}
Special中的所有实体都继承自BaseEntity,其中包含AppInstance
All entities in Special inherits from BaseEntity which contains AppInstance
然后我有一个获得特殊的方法
then i have a method to get the special
@GET
@Path("{ref}")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(value = MediaType.TEXT_PLAIN)
public Special findByGuestRef(@PathParam("ref") String pRefeference) {
// find the special and return it
return special;
}
在特殊实体上我尝试了以下
On the special entity I tried the following
- 添加了jsonIgnoreProperties
- 添加了appInstance的覆盖以使用@JsonIgnore进行注释
- @JsonIdentityInfo
上述链接
- < a href =https://stackoverflow.com/a/29632358/4712391> https://stackoverflow.com/a/29632358/4712391
- 杰克逊序列化:如何忽略超类属性
- 杰克逊自引用导致循环
- https://stackoverflow.com/a/29632358/4712391
- Jackson serialization: how to ignore superclass properties
- jackson self reference leading to cycle
这些解决方案都不起作用。我做错了什么?
none of those solutions works. Am I doing something wrong?
注意:是否也可以编辑特殊的,因为其他实体位于不同的包中而不想编辑它们。
Note: Would it also just be possible to edit special, since the other entities are in a different package and would not like to edit them.
推荐答案
通常在响应中排除属性就像添加 @JsonIgnore $ c $一样简单c>对其getter的注释,但如果您不想将此注释添加到父类,则可以覆盖getter,然后在其上添加注释:
Usually excluding attributes in a response is as easy as adding a @JsonIgnore
annotation to their getters, but if you don't want to add this annotation to a parent class, you could override the getter and then add the annotation on it:
public class Special extends BaseEntity implements Serializable {
...
@JsonIgnore
public ApplicationInstance getAppInstance() {
return this.appInstance;
}
...
}
注意:由于有多个框架,请确保使用正确的 @JsonIgnore
注释,否则将被忽略,请参阅这个答案例如。
NOTE: As there are several frameworks, make sure that you are using the correct @JsonIgnore
annotation or it will be ignored, see this answer for instance.
另一种选择,更手动,只是为了创建一个bean响应将是特殊实例的子集:
Another option, more "manual", is just creating a bean for the response which would be a subset of the Special instance:
@GET
@Path("{ref}")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(value = MediaType.TEXT_PLAIN)
public SpecialDTO findByGuestRef(@PathParam("ref") String pRefeference) {
// find the special and return it
return new SpecialDTO(special);
}
public class SpecialDTO {
//declare here only the attributes that you want in your response
public SpecialDTO(Special sp) {
this.attr=sp.attr; // populate the needed attributes
}
}
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