2016-12-05 63 views
0

我在项目中有一个奇怪的需求。加入两个n:m +属性表(我将用虚拟属性呈现行为)。嵌套n:m +属性JPA

  1. FirstTable(idPlace,idAddress,idSchool,wage)joined 1:m;
  2. SecondTable(idPlace,idAddress,idSchool,数量,idEnterprise)

EDIT(例如模式): enter image description here

当然,我有表地点,住址,学校,企业与他们各自的在实体类中实现的Ids,获取,集合和属性。

CODE:

广场

@Entity 
@Table(name = "Place") 
public class Place implements Serializable { 

/** 
* 
*/ 
private static final long serialVersionUID = 1L; 
@Id 
@GeneratedValue(strategy = GenerationType.AUTO) 
@Column(name = "idLine") 
private Long idLine; 

@OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, mappedBy = "pk.place") 
private List<FirstTable> firstTables; 
} 

地址

@Entity 
@Table(name = "Address") 
public class Address implements Serializable { 

/** 
* 
*/ 
private static final long serialVersionUID = 1L; 
@Id 
@GeneratedValue(strategy = GenerationType.AUTO) 
@Column(name = "idAddress") 
private Long idAddress; 

@OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, mappedBy = "pk.address") 
private List<FirstTable> firstTables; 
} 

学校

@Entity 
@Table(name = "School") 
public class School implements Serializable { 

/** 
* 
*/ 
private static final long serialVersionUID = 1L; 
@Id 
@GeneratedValue(strategy = GenerationType.AUTO) 
@Column(name = "idSchool") 
private Long idSchool; 

@OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, mappedBy = "pk.school") 
private List<FirstTable> firstTables; 
} 

FirstTable

@Entity 
@Table(name = "FirstTable") 
@AssociationOverrides({ @AssociationOverride(name = "pk.school", joinColumns = @JoinColumn(name = "idSchool")), 
    @AssociationOverride(name = "pk.address", joinColumns = @JoinColumn(name = "idAddress")), 
    @AssociationOverride(name = "pk.place", joinColumns = @JoinColumn(name = "idPlace")) }) 
public class FirstTable implements Serializable { 

/** 
* 
*/ 
private static final long serialVersionUID = 1L; 

@EmbeddedId 
protected FirstTablePK pk = new FirstTablePK(); 
} 

FirstTablePK

@Embeddable 
public class FirstTablePK implements Serializable{ 

/** 
* 
*/ 
private static final long serialVersionUID = 1L; 
@ManyToOne 
private Address address; 
@ManyToOne 
private Place place; 
@ManyToOne 
private School school; 
} 

上面提到的表和联接是完全工作。现在我想加入First Table和Second Table。

企业

@Entity 
@Table(name = "Enterprise") 
public class Enterprise implements Serializable { 

private static final long serialVersionUID = 1L; 
@Id 
@GeneratedValue(strategy = GenerationType.AUTO) 
@Column(name = "idEnterprise") 
private Long idEnterprise; 

@OneToMany(取= FetchType.LAZY,级联= CascadeType.ALL,的mappedBy = “pk.enterprise”) 私人列表secondTables;现在 }

为SecondTable我已经遵循同样的逻辑,其连接到企业。为了与FirstTable连接我试过这样:

@Entity 
@Table(name = "SecondTable") 
@AssociationOverrides({ 
     @AssociationOverride(name = "pk.firstTable", joinTable = @JoinTable(
       name = "FirstTable", inverseJoinColumns = { 
       @JoinColumn(name = "idSchool", referencedColumnName = "idSchool"), 
       @JoinColumn(name = "idAddress", referencedColumnName = "idAddress"), 
       @JoinColumn(name = "idPlace", referencedColumnName = "idPlace") })), 
     @AssociationOverride(name = "pk.enterprise", joinColumns = @JoinColumn(name = "idEnterprise")) }) 
public class SecondTable implements Serializable{} 

自己是不是在我的注释工作,我试图做一个inverseJoin到FirstTable表。汇编显示此错误:

"org.hibernate.AnnotationException: A component cannot hold properties split into 2 different tables" 

我试图提供一个MV示例。 在此先感谢,我真的需要你的帮助。

回答

0

几小时后,许多尝试之前,我已经设法解决问题。事实上,我最初想的解决方案要简单得多。

这就是:

@AssociationOverride(name = "pk.firstTable", joinColumns = { 
      @JoinColumn(name = "idSchool"), 
      @JoinColumn(name = "idAddress"), 
      @JoinColumn(name = "idPlace") }), 
    @AssociationOverride(name = "pk.enterprise", joinColumns = @JoinColumn(name = "idEnterprise")) })