尽管使用JsonIgnore，但未能在ManyToMany关系中懒散地初始化角色集合 [英] failed to lazily initialize a collection of role in ManyToMany relationship despite using JsonIgnore

问题描述

我有两个业务对象有很多关系。我正在使用REST服务调用下面给出的DAO方法，并获得政治事件的政治指标列表。然而，虽然DAO中的piList成功给了我政治指标列表，但它仍然给我一个例外

无法懒惰地初始化一个角色集合...

通过引用链：

  org.hibernate.collection.internal.PersistentBag [0] -----> PolIndicator.piList.role 
 org.jboss.resteasy.spi.writerException 
 org.codehaus.jackson。 map.JsonmappingException
  

我已经使用了 @JsonIgnore 在政治指标类中反对政治事件属性，但仍会发生懒惰异常。

我在哪里出错？

  PolEvent {
 
 @Id 
 @Column（name =SEQ_EVENT_ID）
私人BigDecimal ID; 
 
 @Column（name =EVENT_NAME）
 private String eventName; 
 
 @ManyToMany 
 @JoinTable（
 name =POL_LINK_INDCTR
 joinColumns = {@ JoinCo lumn（name =SEQ_EVENT_ID）}，
 inverseJoinColumns = @ JoinColumn（name =SEQ_PI_ID）
）
 private List< PolIndicator> piList; 
 
 
 
 PolIndicator {
 
 @Id 
 @Column（name =SEQ_PI_ID）
 private BigDecimal id; 
 
 @Column（name =POL_IND_NAME）
 private String piName; 
 
 @ManyToMany（mappedBy =piList）
 @JsonIgnore 
 private List< PolEvent>活动列表; 
 
 $ / code> 

DAO Layer代码



  public List< PolIndicator> getPiList（String eventId）{
 
 Criteria criteria = session.createCriteria（PolEvent.class）; 
 criteria.add（Restrictions.eq（id，id）; 
 PolEvent polEvent = new PolEvent（）; 
 polEvent = criteria.uniqueResult（）; 
 piList = polEvent .getPiList（）; 
 return piList（）; 
} 
  




解决方案

您需要将注释移至getter方法：



  @JsonIgnore 
 public List< PolEvent> getEventList（）{
 return eventList; 
} 
  




I have two business objects having many too many relationships. I am using a REST service to call the DAO method given below and get a list of political indicators for a political event. However though the piList in DAO successfully gives me the list of Political Indicators but it still gives me an exception

Failed to lazily intialize a collection of role...

through reference chain:

org.hibernate.collection.internal.PersistentBag[0]----->PolIndicator.piList.role
org.jboss.resteasy.spi.writerException
org.codehaus.jackson.map.JsonmappingException"

I have used @JsonIgnore in the Political Indicator class against the political event property but still the lazy exception happens.

Where am I going wrong?

PolEvent {

    @Id
    @Column(name="SEQ_EVENT_ID")
    private BigDecimal id;

    @Column(name="EVENT_NAME")
    private String eventName;

    @ManyToMany
    @JoinTable(
        name="POL_LINK_INDCTR"
        joinColumns={@JoinColumn(name="SEQ_EVENT_ID")},
        inverseJoinColumns=@JoinColumn(name="SEQ_PI_ID")
    )
    private List <PolIndicator> piList;
}


PolIndicator {

    @Id
    @Column(name="SEQ_PI_ID")
    private BigDecimal id;

    @Column(name="POL_IND_NAME")
    private String piName;

    @ManyToMany(mappedBy="piList")
    @JsonIgnore
    private List <PolEvent> eventList; 
}

DAO Layer Code

public List <PolIndicator> getPiList (String eventId) {

    Criteria criteria = session.createCriteria(PolEvent.class);
    criteria.add(Restrictions.eq("id",id);
    PolEvent polEvent = new PolEvent();
    polEvent=criteria.uniqueResult();
    piList = polEvent.getPiList();
    return piList();
}

解决方案

You need to move the annotation to the getter method:

@JsonIgnore
public List <PolEvent> getEventList() {
    return eventList;
}

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