使用 OnetoMany 和 ManytoOne 映射时的无限递归循环（双向）

Question

在我的 Spring Boot Rest 应用程序中，我有三个模型类

User, Business, Review

用户.java

@OneToMany(cascade = CascadeType.ALL, mappedBy = "partner",fetch = 
 FetchType.LAZY)
private Set<Business> business;
@OneToMany(fetch=FetchType.LAZY,cascade=CascadeType.ALL,mappedBy="user")
private List<Review> reviews;

Business.java

@OneToMany(fetch=FetchType.LAZY,cascade=CascadeType.ALL,mappedBy="business")
private List<Review> reviews;

    @JoinTable(name = "business_service",
            joinColumns = { @JoinColumn(name = "business_id_fk") },
            inverseJoinColumns = { @JoinColumn(name = "serviceIdFk") })
        private List<ServiceVO> services = new ArrayList<ServiceVO>();

Review.java

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "businsessIdFk")
private Business business;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "addedBy", nullable = false)
private User user;

当我尝试通过 Repository 查找具有 business_id 的业务时，我得到一个无限递归 Json 列表。 我必须找到带有 user_id 的用户，但也会发生同样的事情。

任何帮助将不胜感激

注意：我已经使用了答案中提到的 JsonIgnore。它给我带来了另一个杰克逊绑定错误

   com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No 
   serializer found for class 
   org.hibernate.proxy.pojo.bytebuddy.ByteBuddyInterceptor and no 
   properties discovered to create BeanSerializer (to avoid exception, 
   disable 
   SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: 
   com.ovoox.model.Business["services"]- 
  >org.hibernate.collection.internal.PersistentBag[0]- 
   com.ovoox.model.ServiceVO$HibernateProxy$
   TOMK9CML["hibernateLazyInitializer"])

Answer 1

在这种情况下，用户通过一对多关系映射到评论，并且评论再次通过多对关系映射到用户。因此，每当您检索用户时，您都会获得评论列表，而评论列表又是用户，导致这是一个 JSON 无限递归。要摆脱这种情况，请尝试以下代码：

在 Review.java POJO

import org.codehaus.jackson.annotate.JsonIgnore;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "businsessIdFk")
private Business business;

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "addedBy", nullable = false)
private User user;

@JsonIgnore
public Business getBusiness(){
    return business;
}

@JsonIgnore
public User getUser(){
    return user;
}

使用@JsonIgnore 删除此对象以避免递归。