在另一个实体中被引用的组合键的一个Id [英] One Id of composite key to be referenced in another entity

问题描述

表1只有两列构成一个组合键

表2 id列正在生成。

Table1的一个属性的值我正在提供，对于第二个属性，我需要它来提取Table2的生成值。
这里是我到目前为止 -

复合主键：

  public class PKClass implements Serializable 
 {
 private static final long serialVersionUID = -2092390836751020965L; 
 public PKClass（）{} 
 public PKClass（long actId，long actAttId）{
 this.actvId = actId; 
 this.actvAtId = actAttId; 
} 
 
 private long actvId; 
 private private actvAtId; 
 // getters，setters，equals，hashcode 
} 
  

实体类1 ：

pre $ @ $ $ c $ @Entity @Table（name =Table1）
@IdClass（PKClass.class）
public class AtLinkData实现Serializable
{
@Id @Column（name =ACT_ID，nullable = false）
private private actvId;
@Id @Column（name =ACT_AT_ID）
private private actvAtId;
@OneToOne（cascade = CascadeType.ALL，fetch = FetchType.EAGER，mappedby =atLinkData）
@JoinColumn（name =ACT_AT_ID）
私人AtData atData;
// getters，setters
}

实体类2：

  @Entity @Table（name =Table2）
公共类AtData实现Serializable 
 {
 @TableGenerator（name =somename，table =sometable，pkColumnName =somecolumn，valueColumnName =valuename，pkColumnValue =Table2，allocationSize = 1）
 @Id @GeneratedValue（strategy = GenerationType。 TABLE，generator =somename）
 @Column（name =ACT_AT_ID）
 private Long id; 
 //其他变量
 @OneToOne（fetch = FetchType.LAZY）
 @JoinColumn（name =ACT_AT_ID）
私人AtLinkData atLinkData; 
 // getters setters 
} 
  

我一直在尝试不同的事情，但使用上面的代码，我得到错误：

 引起：org.hibernate.MappingException：用于atLinkData的断列映射.id of：com.test.database.AtData 
  

解决方案

这是我如何解决它：

AtLinkData.java

  @ Id 
 @GeneratedValue（generator =foreignGenerator）
 @ org.hibernate.annotations.GenericGenerator（name =foreignGenerator，strategy =foreign，parameters = @Parameter（name =property，值）=atData））
 @Column（name =ACT_AT_ID）
私人长期actvAtId; 
 
 @OneToOne（cascade = CascadeType.ALL，fetch = FetchType.EAGER）
 @JoinColumn（name =ACT_AT_ID，insertable = false，updatable = false）
 private AtData atData; 
 // getters，setters 
  

AtData.java

  @OneToOne（fetch = FetchType.LAZY，mappedBy =atData）
私人AtLinkData atLinkData; 
  

感谢 @CycDemo 寻求帮助。

• Table 1 has only two columns which form a composite key.
• Table 2 id column is being generated.
• Value for one property of Table1 I am supplying and for second property I need it to pick up the generated value of Table2. Here is what I have so far-

Composite primary key:

public class PKClass implements Serializable
{
    private static final long serialVersionUID = -2092390836751020965L;
    public PKClass(){}
    public PKClass(long actId, long actAttId){
        this.actvId = actId;
        this.actvAtId = actAttId;
    }

    private long actvId;
    private long actvAtId;
    // getters, setters, equals, hashcode
}

Entity class 1:

@Entity @Table(name = "Table1")
@IdClass(PKClass.class)
public class AtLinkData implements Serializable
{
    @Id @Column(name = "ACT_ID", nullable = false)
    private long actvId;
    @Id @Column(name = "ACT_AT_ID")
    private long actvAtId;
    @OneToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER, , mappedBy = "atLinkData")
    @JoinColumn(name = "ACT_AT_ID")
    private AtData atData;
    // getters, setters
}

Entity class 2:

@Entity @Table(name = "Table2")
public class AtData implements Serializable
{
    @TableGenerator(name = "somename", table = "sometable", pkColumnName = "somecolumn", valueColumnName = "valuename", pkColumnValue = "Table2", allocationSize = 1)
    @Id @GeneratedValue(strategy = GenerationType.TABLE, generator = "somename")
    @Column(name = "ACT_AT_ID")
    private Long id;
    // other variables
    @OneToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "ACT_AT_ID")
    private AtLinkData atLinkData;
    // getters setters
}

I have been trying different things, but with the code above, I am getting the error:

Caused by: org.hibernate.MappingException: broken column mapping for: atLinkData.id of: com.test.database.AtData

解决方案

Here is how I solved it:

AtLinkData.java

@Id
@GeneratedValue(generator = "foreignGenerator")
@org.hibernate.annotations.GenericGenerator(name = "foreignGenerator", strategy = "foreign", parameters = @Parameter(name = "property", value = "atData"))
@Column(name = "ACT_AT_ID")
private long actvAtId;

@OneToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(name = "ACT_AT_ID",insertable=false,updatable=false)
private AtData atData;
// getters, setters

AtData.java

@OneToOne(fetch = FetchType.LAZY, mappedBy="atData")
private AtLinkData atLinkData;

Thanks @CycDemo for your help.

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