java - 直接 self 引用导致循环 Ebean 和 Jackson

Question

我有三个模型，即 UserAccount、CompanyMst 和 Property Master。

我能够将数据插入到所有这些中，但是在将列表作为 JSon 对象检索时，出现以下错误。

型号如下。

@Entity

public class UserAccount extends Model {
@Id
public Long id;

@Constraints.Email
public String email = "";

public String password = "";

public String firstname = "";

public String lastname = "";

public String telno = "";

public String activationbytecode = "";

public String authtoken;

public String createToken() {
    authtoken = UUID.randomUUID().toString();
    save();
    return authtoken;
}

public void deleteAuthToken() {
    authtoken = null;
    save();
}

@Formats.DateTime(pattern = "yyyy-MM-dd hh:mm:ss")
public Date createdOn = new Date();

@ManyToOne
public UserAccount createdby;

@Formats.DateTime(pattern = "yyyy-MM-dd hh:mm:ss")
public Date activatedOn;

public boolean activationstatus = false;

public boolean accountstatus = false;

@ManyToOne
@Constraints.Required
@JsonBackReference
public CompanyMst company;

@ManyToOne
public Roles role;

@Formats.DateTime(pattern = "yyyy-MM-dd hh:mm:ss")
public Date updatedon;

@ManyToOne
public UserAccount updateby;




}

公司模式如下。

  @Entity

public class CompanyMst extends Model {
    @Id
    public Long id;

    @Constraints.Required
    public String name;

    @Constraints.Required
    public Integer buildingmanaged;

    public Boolean isactive = false;

    @Constraints.Required
    public String address;

    @Constraints.Required
    @Constraints.Email
    public String email;

    @Constraints.Required
    public String telno;

    @Formats.DateTime(pattern="yyyy-MM-dd hh:mm:ss")
    public Date subscriptiondatefrom;

    @Formats.DateTime(pattern="yyyy-MM-dd hh:mm:ss")
    public Date subscriptiondateto;

    public Boolean subscriptionisexpired = false;

    @Formats.DateTime(pattern="yyyy-MM-dd hh:mm:ss")
    public Date createdon = new Date();

    @ManyToOne
    public UserAccount createdbyuser;

    @Formats.DateTime(pattern="yyyy-MM-dd hh:mm:ss")
    public Date updatedon;

    @ManyToOne
    public UserAccount updateby;

    public static Finder<Long,CompanyMst> find = new Finder <>(CompanyMst.class);

    public static CompanyMst findByCompanyName(String name){
        return find.query().where().eq("name",name).findOne();
    }

    public static int getCompanyCount() {
        return find.query().where().eq("isactive",true).findCount();
    }





}

属性模型如下

@Entity

public class PropertyMst extends Model {
@Id
public Long id;

public String code = "";

public String propertyname = "";

public String description = "";

public Boolean isactive = true;

public String plotlandnumber = "";

public Boolean islettable = Boolean.TRUE;

public Boolean depositrequired = Boolean.TRUE;

@Constraints.Required
public Integer nooflettableunits;

public String address ="";

@ManyToOne
@JsonManagedReference
public CompanyMst companyMst;

@WhenCreated
@Formats.DateTime(pattern="yyyy-MM-dd hh:mm:ss")
public Date createdon = new Date();

// @WhoCreated
@ManyToOne
public UserAccount createdbyuser;


@Formats.DateTime(pattern="yyyy-MM-dd hh:mm:ss")
public Date updatedon;

// @WhoModified
@ManyToOne
public UserAccount updatedby;

public static Finder<Long,PropertyMst> find = new Finder <>(PropertyMst.class);

public static PropertyMst findByPropertyName(String propertyname){

    return PropertyMst.find.query().where().eq("propertyname",propertyname).findOne();
}

public static List<PropertyMst> propertyMstList(){
    return new ArrayList<>(PropertyMst.find.query().where().eq("isactive",true).findList());

}

public static Map<String, String> options(CompanyMst companyMst){
    LinkedHashMap<String,String> options=new LinkedHashMap<String,String>();
    for(PropertyMst c:PropertyMst.find.query().where()
            .eq("isactive",true)
            .eq("companyMst",companyMst)
            .findList()){
        options.put(c.id.toString(),c.propertyname);
    }

    return options;
}

public static int getTotalProperties(){
    return PropertyMst.find.all().size();
}

public static int getCompanyProperties(CompanyMst companyMst){
    return PropertyMst.find.query().where().eq("companyMst", companyMst).findCount();
}

public static PropertyMst getPropertyByCompany(CompanyMst companyMst){
    return PropertyMst.find.query().where().eq("companyMst",companyMst).findOne();
}

public static List<PropertyMst> getPropertyByCompanyList(CompanyMst companyMst){
    return PropertyMst.find.query().where().eq("companyMst",companyMst).findList();
}

}

不知道为什么会收到此错误

Direct self-reference leading to cycle (through reference chain: io.ebean.common.BeanList[0]->models.PropertyMst["companyMst"]->models.CompanyMst["createdbyuser"]->models.UserAccount["createdby"]) at play.libs.Json.toJson

Answer 1

添加用户模型

@JsonBackReference
@ManyToOne
public UserAccount createdby;