JPA许多一对多加入与复合键表实体“空ID生成”

Question

这是我的实体：

public class Account extends AbstractEntity<Long> { 

    @Id 
    @SequenceGenerator(name = "accountSequence", sequenceName = "SQ_ACCOUNTS", allocationSize = 1) 
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "accountSequence") 
    @Column(name = "ACC_ID", nullable = false) 
    private Long id; 
... 
} 

public class Integration extends AbstractEntity<Long> { 

    @Id 
    @SequenceGenerator(name = "integrationSequence", sequenceName="SQ_INTEGRATIONS", allocationSize = 1) 
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "integrationSequence") 
    @Column(name = "INT_ID", nullable = false) 
    private Long id; 
... 
public void addIntegration(Integration integration) { 
     IntegrationAccount association = new IntegrationAccount(); 
      // This does not help 
     //association.setIntAccountsPK(new IntAccountsPK(integration.getId(), this.getId())); 
     association.setAccount(this); 
     association.setIntegration(integration); 
     this.integrationAccounts.add(association); 
     integration.getIntAccountsCollection().add(association); 
    } 
} 

这是实体连接表

@Entity 
@Table(name = "INT_ACCOUNTS") 
public class IntegrationAccount { 

    @EmbeddedId 
    protected IntAccountsPK intAccountsPK; 

    @JoinColumn(name = "ACC_ID", referencedColumnName = "ACC_ID", insertable = false, updatable = false) 
    @ManyToOne 
    private Account account; 

    @JoinColumn(name = "INT_ID", referencedColumnName = "INT_ID", insertable = false, updatable = false) 
    @ManyToOne 
    private Integration integration; 
... 
} 
@Embeddable 
public class IntAccountsPK implements Serializable { 

    @Column(name = "INT_ID", nullable = false) 
    private Long intId; 

    @Column(name = "ACC_ID", nullable = false) 
    private Long accId; 
... 
} 

当我做：org.hibernate.id.IdentifierGenerationException：

account.addIntegrations(integrations.getTarget()); 
account.setCustomer(customer); 
accountService.save(account); 

我在我的日志 所致得到这个产生的空号为：类com.dhl.dcc.domain.IntegrationAccount

我没有关于这种映射的许多知识，你可以请告诉我如何改善这种映射（实体连接表都被保留），以及如何用相关的集成保存帐户？谢谢。

Answer 1

你可以为你的IntegrationAccount创建一个ID字段，然后为您的两个字段的唯一约束。

@Entity 
@Table(name = "INT_ACCOUNTS", 
     uniqueConstraints=@UniqueConstraint(columnNames={"ACC_ID", "INT_ID"})) 
public class IntegrationAccount { 

    @Id 
    private Long id; 

    @JoinColumn(name = "ACC_ID", referencedColumnName = "ACC_ID", insertable = false, updatable = false) 
    @ManyToOne 
    private Account account; 

    @JoinColumn(name = "INT_ID", referencedColumnName = "INT_ID", insertable = false, updatable = false) 
    @ManyToOne 
    private Integration integration; 
... 
} 

工程就像一个魅力！

Answer 2

我知道这个问题已经被标记为解决，但我接受的答案不同意。此答案通过在表INT_ACCOUNTS中添加无用的列（新ID）来修改数据模型。还有另一种方法可以在不修改数据模型的情况下在Hibernate中解决这个问题：

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

    @Id 
    @ManyToOne 
    @JoinColumn(name = "INT_ID_FK") 
    private Integration integration; 

    @Id 
    @ManyToOne 
    @JoinColumn(name = "ACC_ID_FK") 
    private Account account; 
} 

@Entity 
@Table(name = "INTEGRATIONS") 
public class Integration { 

    @Id 
    @SequenceGenerator(name = "integrationSequence", sequenceName = "SQ_INTEGRATIONS", allocationSize = 1) 
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "integrationSequence") 
    @Column(name = "INT_ID") 
    private Long id; 
} 

@Entity 
@Table(name = "ACCOUNTS") 
public class Account { 

    @Id 
    @SequenceGenerator(name = "accountSequence", sequenceName = "SQ_ACCOUNTS", allocationSize = 1) 
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "accountSequence") 
    @Column(name = "ACC_ID") 
    private Long id; 
}