如何在Hibernate中

Question

bean屬性的一個映射到很多我有兩個表vehicleregister和groupdetails對我有豆類VehicleRegisterBean和GroupDetails公共字段是groupid。這1組可以包含爲，我執行一對多關係，我已經定義了bean作爲，

VehicleRegiserBean，

@Entity 
@Table(name = "vehicle_register") 
public class VehicleRegisterBean { 
// somefields 

@ManyToOne 
@JoinColumn(name="groupid", nullable=false) 
private GroupDetails groupDetails; 

//getter setters 
} 

和

GroupDetails許多車輛，

@Entity 
@Table(name = "group_details") 
public class GroupDetails { 

//some fields 

@OneToMany(mappedBy="GroupDetails") 
private Set<VehicleRegisterBean> vehicleRegisterBean; 

//getters setters 
} 

但我收到異常，

org.hibernate.AnnotationException: mappedBy reference an unknown target entity property: com.abc.its.beans.VehicleRegisterBean.GroupDetails in com.abc.its.beans.GroupDetails.vehicleRegisterBean 
at org.hibernate.cfg.annotations.CollectionBinder.bindStarToManySecondPass(CollectionBinder.java:685) 
at org.hibernate.cfg.annotations.CollectionBinder$1.secondPass(CollectionBinder.java:645) 
at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:65) 
at org.hibernate.cfg.Configuration.originalSecondPassCompile(Configuration.java:1716) 
at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1423) 

任何人都可以幫助我解決這個問題。

Answer 1

爲mappedBy屬性的值表示您VehicleRegisterBean類，這是該領域，你在這裏聲明名稱， groupDetails但您使用的是GroupDetails的mappedBy。

因此，hibernate試圖在VehicleRegisterBean中尋找屬性GroupDetails並且說它無法找到該屬性。多數民衆贊成在錯誤說：

mappedBy reference an unknown target entity property: 
com.abc.its.beans.VehicleRegisterBean.GroupDetails 

Answer 2

變化

@OneToMany(mappedBy="GroupDetails") 

到

@OneToMany(mappedBy="groupDetails") 

是

private GroupDetails groupDetails;