Question

大家好，我在数据库中的updated_at列遇到了一些问题。我正在使用hibernate，当我更新模型时，除了@preUpdate方法之外，一切正常。我的所有应用程序模型都在扩展这个基本模型：

@MappedSuperclass
@Cache(usage = CacheConcurrencyStrategy.TRANSACTIONAL)
@Access(AccessType.PROPERTY)
public class BaseModel implements Serializable {

    // VARIABLES ---------------------------------------------------------------
private Integer globalKey;
private Integer id;
private Date createdAt;
private Date updatedAt;
private Date deletedAt;
private User createUser;
private User updateUser;
private User deleteUser;

    // CONSTRUCTORS ------------------------------------------------------------

    // GETTERS AND SETTERS -----------------------------------------------------

    // [hashCode, equals and toString methods] ---------------------------------

    @PrePersist
    protected void onCreate() {
        createdAt = new Date();
    }

    @PreUpdate
    protected void onUpdate() {
        updatedAt = new Date();
    }
}

这是DAO中用于更新的方法：

public MYOBJECT updateEntity(MYOBJECT entity, User updateUser) throws Exception {
    entity.setUpdateUser(updateUser);

    sessionFactory.getCurrentSession().update(entity);

    return entity;
}

我错过了什么吗？在我的数据库中，我看到：

---------------------------------------------
| id    | updated_at    | id_user_update    |
| 1     | NULL          | 1                 |
---------------------------------------------

Answer 1

I've found the answer to my problem here.

But just a little bit modified... Here is my code:

First of all I've removed from the BaseModel class these two methods:

@PrePersist
protected void onCreate() {
    createdAt = new Date();
}

@PreUpdate
protected void onUpdate() {
    updatedAt = new Date();
}

Then I've created a BaseTimestamps interface, used to set up my createdAt and updatedAt variables

public interface BaseTimestamps {

    /**
     * On create event.
     * used to setup a the creation variable.
     * 
     * @param createdAt
     */
    void setCreatedAt(Date createdAt);

    /**
     * On update event.
     * used to setup a the update variable.
     * 
     * @param updatedAt
     */
    void setUpdatedAt(Date updatedAt);
}

Finally I've created two listeners for the hibernate session factory in the hibernate.cfg.xml file.

// SAVE LISTENER
public class SaveListener extends DefaultSaveEventListener {

    @Override
    public void onSaveOrUpdate(SaveOrUpdateEvent event) {
        if (event.getObject() instanceof BaseTimestamps) {
            BaseTimestamps record = (BaseTimestamps) event.getObject();
            record.setCreatedAt(new Date());
        }

        super.onSaveOrUpdate(event);
    }

}

// UPDATE LISTENER
public class UpdateListener extends DefaultUpdateEventListener {

    @Override
    public void onSaveOrUpdate(SaveOrUpdateEvent event) {
        if (event.getObject() instanceof BaseTimestamps) {
            BaseTimestamps record = (BaseTimestamps) event.getObject();
            record.setUpdatedAt(new Date());
        }

        super.onSaveOrUpdate(event);
    }

}

And here is my hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>
    <mapping class="my.package.MyModel"/>
    // ............................
    <mapping class="my.package.OtherModel"/>  
      <event type="save">
         <listener class="my.package.SaveListener"/>
      </event>   
      <event type="update">
         <listener class="my.package.UpdateListener"/>
      </event>
  </session-factory>
</hibernate-configuration>

When I perform creation or updates, everything works fine and I see in my database the correct values.

Hibernate预更新不更新字段

1 个答案: