当我尝试创建插入查询时如何使用休眠@EmbeddedId

Question

I am using hibernate and i have created entities on the java side using hibernates. One of my DB table has multiple columns as primary key and hibernate used @EmbeddedId to deal with that.

My problem is that when i create an insert query i get this error:

"null id generated for:class com.iu.eblood.model.Eventtypeofevent"

to set Id,i need to create an objejt for this EmbeddedId and when i create and set this Id, another problem appeared:

"The target name "EVENTID" is specified more than once for assignment in the same SQL statement"

i guess,the reson for error is both my Eventtypeofevent object and EventtypeofeventPK object(class created by hibernate for EmbeddedId) actually show the same attribute.

Here is my class:

@Entity
public class Eventtypeofevent implements Serializable {

    private static final long serialVersionUID = 1L;
    private EventtypeofeventPK id;
    private Timestamp createddate;
    private Timestamp deleteddate;
    private String isactive;
    private Event event;
    private Eventtype eventtype;

    public Eventtypeofevent() {
    }


    @EmbeddedId
    public EventtypeofeventPK getId() {
        return this.id;
    }

    public void setId(EventtypeofeventPK id) {
        this.id = id;
    }
....... getter and setter

and other class for EmbeddedId:

    @Embeddable
public class EventtypeofeventPK implements Serializable {
    //default serial version id, required for serializable classes.
    private static final long serialVersionUID = 1L;
    private long eventid;
    private int eventtypeid;
...... getter and setter

Answer 1

I used @EmbeddedId like this, I am not sure if it can help:

@EmbeddedId
@AttributeOverrides({
  @AttributeOverride(name = "orgId", column = @Column(name = "ORG_ID", nullable = false,     precision = 12, scale = 0)),
  @AttributeOverride(name = "configId", column = @Column(name = "CONFIG_ID", nullable = false, precision = 9, scale = 0)) })
  public [EmbeddedId Object] getId() {
    return id;
  }