"org.hibernate.DuplicateMappingException"错误是什么意思？

Question

我试图强制JPA/Hibernate生成并只使用小写的表名.我已经实现了这样的NamingStrategy:

public class MyNamingStrategy extends DefaultNamingStrategy {

  @Override
  public String classToTableName(String className) {
    return super.classToTableName(className).toLowerCase();
  }
}

我通过在persistence.xml中设置此属性来应用它:

<property name="hibernate.ejb.naming_strategy" value="entities.strategy.MyNamingStrategy"/>

当我这样做时,我得到这个堆栈跟踪:

SEVERE: Exception while invoking class org.glassfish.persistence.jpa.JPADeployer prepare method
org.hibernate.DuplicateMappingException: Same physical table name [planning] references several logical table names: [Planning], [OrderProductMan_Planning]
        at org.hibernate.cfg.Configuration$MappingsImpl.addTableBinding(Configuration.java:2629)
        at org.hibernate.cfg.annotations.TableBinder.buildAndFillTable(TableBinder.java:254)
        at org.hibernate.cfg.annotations.TableBinder.bind(TableBinder.java:177)

什么是

相同的物理表名称[planning]引用了多个逻辑表名称:[Planning],[OrderProductMan_Planning]

意思？

来自错误的实体,尽可能简化.如果你需要休息,请告诉我.

@Entity
public class Planning implements Serializable {

  @Id
  @GeneratedValue(strategy = GenerationType.AUTO)
  private Integer id;

  private Integer qty;

  @ManyToOne
  private OrderProductMan orderProduct;

  ....
}


@Entity
@Table
public class OrderProductMan implements Serializable {

  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  @Basic(optional = false)
  private Integer opId;

  @Basic(optional = false)
  private int qty;

  @ManyToOne(optional = false)
  private ProductMan produse;

  @ManyToOne(optional = false)
  private OrderMan orders;

  @Transient
  private int totalScheduled;

  @Transient
  private int totalProduced;
   // ...
 }

Answer 1

博格丹，感谢您发布此内容。我在 Linux 上使用 Hibernate/JPA/MySQL 时，对于 Unix/Windows 可移植性的区分大小写的表名也遇到了类似的问题。

和您一样，我开始通过在 META-INF/persistence.xml 文件中配置自定义 NamingStrategy 将表名绑定为全部小写：

<property name="hibernate.ejb.naming_strategy" value="my.package.LowerCaseNamingStrategy" />

我得到了同样的异常：org.hibernate.DuplicateMappingException：相同的物理表名称...通过使用调试器，我突然顿悟，也许我一开始就没有使用DefaultNamingStrategy！所以我将基类更改为 org.hibernate.cfg.EJB3NamingStrategy。我相信这在使用 JPA Annotations 时更合适！这是我最终的命名策略：

package my.package;

import org.apache.commons.lang.StringUtils;
import org.hibernate.cfg.EJB3NamingStrategy;

public class LowerCaseNamingStrategy extends EJB3NamingStrategy {
    @Override
    public String classToTableName(String className) {
        return StringUtils.lowerCase(super.classToTableName(className));
    }

    @Override
    public String collectionTableName(String ownerEntity, String ownerEntityTable, String associatedEntity,
            String associatedEntityTable, String propertyName) {
        return StringUtils.lowerCase(super.collectionTableName(ownerEntity, ownerEntityTable, associatedEntity, associatedEntityTable, propertyName));
    }

    @Override
    public String logicalCollectionTableName(String tableName, String ownerEntityTable, String associatedEntityTable,
            String propertyName) {
        return StringUtils.lowerCase(super.logicalCollectionTableName(tableName, ownerEntityTable, associatedEntityTable, propertyName));
    }

    @Override
    public String tableName(String tableName) {
        return StringUtils.lowerCase(super.tableName(tableName));
    }
}

PS：dursun 之前的解决方案对我不起作用。