There is a cycle in the hierarchy解决

前言：

　　在一次项目中，分页查询公告列表信息后，在遍历查询到的公告列表时出现了死循环“There is a cycle in the hierarchy”错误，分析原因是因为在公告实体类中包含了商铺对象导致，所以在遍历的时候需要过滤掉商铺这个字段。

代码示例:

公告实体类

/**
 * 
 * 电商-公告
 * EshopNotice entity.*/
@Entity
@Table(name = "eshop_notice")
@JsonIgnoreProperties(value={"shop"})
public class EshopNotice implements java.io.Serializable {

    // Fields

    // 系统ID     
    private String sysid;
    
    //时间戳记
    private String tstamp;
    
    // 操作日期
    private String operationDateTime;
    
    // 操作员
    private String operator;
    
    /**
     * 商铺
     */
    private CoreCompany shop;
    
    /**
     * 标题
     */
    private String title;
    
    /**
     * 内容
     */
    private String content;
    
    /**
     * 发布日期
     */
    private String publishDatetime;
    
    /**
     * 状态
     */
    private String status;

    // Constructors
    /** default constructor */
    public EshopNotice() {
    }
    /** minimal constructor */
    public EshopNotice(String tstamp, String operationDateTime, String operator, String title, String content,
            String publishDatetime, String status) {
        this.tstamp = tstamp;
        this.operationDateTime = operationDateTime;
        this.operator = operator;
        this.title = title;
        this.content = content;
        this.publishDatetime = publishDatetime;
        this.status = status;
    }

    /** full constructor */
    public EshopNotice(String tstamp, String operationDateTime, String operator, CoreCompany shop, String title,
            String content, String publishDatetime, String status) {
        this.tstamp = tstamp;
        this.operationDateTime = operationDateTime;
        this.operator = operator;
        this.shop = shop;
        this.title = title;
        this.content = content;
        this.publishDatetime = publishDatetime;
        this.status = status;
    }

    // Property accessors
    @GenericGenerator(name = "generator", strategy = "uuid.hex")
    @Id
    @GeneratedValue(generator = "generator")
    @Column(name = "sysid", unique = true, nullable = false, length = 32)
    public String getSysid() {
        return sysid;
    }
    public void setSysid(String sysid) {
        this.sysid = sysid;
    }    
    @Column(name = "tstamp", nullable = false, length = 20)
    public String getTstamp() {
        return tstamp;
    }
    public void setTstamp(String tstamp) {
        this.tstamp = tstamp;
    }
    @Column(name = "operationdatetime", nullable = false, length = 20)
    public String getOperationDateTime() {
        return operationDateTime;
    }
    public void setOperationDateTime(String operationDateTime) {
        this.operationDateTime = operationDateTime;
    }
    @Column(name = "operator", nullable = false, length = 32)
    public String getOperator() {
        return this.operator;
    }
    public void setOperator(String operator) {
        this.operator = operator;
    }  
    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "shop", nullable = false)
    public CoreCompany getShop() {
        return this.shop;
    }
    public void setShop(CoreCompany shop) {
        this.shop = shop;
    }
    @Column(name = "title", nullable = false, length = 128)
    public String getTitle() {
        return this.title;
    }
    public void setTitle(String title) {
        this.title = title;
    }
    @Column(name = "content", nullable = false, length = 2000)
    public String getContent() {
        return this.content;
    }
    public void setContent(String content) {
        this.content = content;
    }
    @Column(name = "publishdatetime", nullable = false, length = 20)
    public String getPublishDatetime() {
        return publishDatetime;
    }
    public void setPublishDatetime(String publishDatetime) {
        this.publishDatetime = publishDatetime;
    }
    @Column(name = "status", nullable = false, length = 32)
    public String getStatus() {
        return this.status;
    }
    public void setStatus(String status) {
        this.status = status;
    }

分页查询遍历

@RequestMapping("/listPage.html")
    public JSONTableDateView noticeList(HttpServletRequest request,PageQuery pageQuery)  {    
        
        CoreMember member=(CoreMember)request.getSession().getAttribute("member");
        CoreCompany company=coreCompanyService.getByMemberId(member.getSysid());
                
      //分页查询
      PageResults<EshopNotice> pageResults = noticeService.noticeList(pageQuery,company.getSysid());
      //设置页面参数
      JSONArray data = new JSONArray();
      for(EshopNotice eshopNotice : pageResults.getResults()){
        JsonConfig jsonConfig=new JsonConfig();
        jsonConfig.setJsonPropertyFilter(new PropertyFilter() {
                @Override
                public boolean apply(Object arg0, String arg1, Object arg2) {
                  //过滤段公告中的shop字段，否则会无限死循环
                    if (arg1.equals("shop") ) {
                        return true;
                    } else {
                        return false;
                    }
                }
            });
        JSONObject dataTemp =JSONObject.fromObject(eshopNotice,jsonConfig);
        dataTemp.put("title", eshopNotice.getTitle());
        dataTemp.put("content", eshopNotice.getContent());
        if(eshopNotice.getStatus().equals("00")){
             dataTemp.put("status","申请");
        }else{
            dataTemp.put("status","审核通过");
        }       
        dataTemp.put("publishDatetime",eshopNotice.getPublishDatetime());
        dataTemp.put("sysid", eshopNotice.getSysid());
        data.add(dataTemp);
      }
      JSONTableDateView jSONTableDateView  = new JSONTableDateView(pageQuery, pageResults, data);     
      return jSONTableDateView;
    }        
    

 

转载于:https://www.cnblogs.com/guzhou-ing/p/7201612.html