sabri sabri - 6 months ago 28
Java Question

Persisting 2 table with the same generated id

I try to persist one parent entity which is joined with another child entity, but the problem is that the id is not generated for this child when persisting so I have this error :

[org.hibernate.engine.jdbc.spi.SqlExceptionHelper] ORA-01400: cannot insert NULL into ("L2S$OWNER"."SABRI"."TRANSITION_MATRIX_ID")


there is the child Entity :

@Data
@Entity
@IdClass(MyLibrarySabriEntityPK.class)
@Table(name = "SABRI", schema = "L2S$OWNER", catalog = "")

public class MyLibrarySabriEntity extends ActionForm {
@Access(AccessType.FIELD)
@Id
@ManyToOne
@JoinColumn(name = "TRANSITION_MATRIX_ID", referencedColumnName = "ID_TRANSITION_MATRIX")
private MyLibraryTestEntity sabriEntity;

@Id
private String RATING_ID_ROW;

@Id
private String RATING_ID_COL;


@Basic
@Column(name = "TRANSITION_PROBABILITY", nullable = true, insertable = true, updatable = true, precision = 20)
private Double TRANSITION_PROBABILITY;}


the PK class :

@Data
public class MyLibrarySabriEntityPK implements Serializable {
private String TRANSITION_MATRIX_ID;
private String RATING_ID_ROW;
private String RATING_ID_COL;


public MyLibrarySabriEntityPK(String TRANSITION_MATRIX_ID,String RATING_ID_COL,String RATING_ID_ROW ){
this.TRANSITION_MATRIX_ID=TRANSITION_MATRIX_ID;
this.RATING_ID_COL = RATING_ID_COL;
this.RATING_ID_ROW= RATING_ID_ROW;
}


}

there is the parent Entity:

@Data
@Entity
@Table(name = "TEST", schema = "L2S$OWNER", catalog = "")
public class MyLibraryTestEntity extends ActionForm {

@Access(AccessType.FIELD)
@OneToMany(mappedBy = "sabriEntity", cascade = CascadeType.PERSIST)
private final List<MyLibrarySabriEntity> entities = new ArrayList<MyLibrarySabriEntity>(25);

public void addEntitysabri(MyLibrarySabriEntity entity) {
getEntities().add(entity);
entity.setSabriEntity(this);
}

@Id
@GeneratedValue(strategy = GenerationType.AUTO, generator = "IdGenerated")
@GenericGenerator(name = "IdGenerated", strategy = "dao.Identifier")
@Column(name = "ID_TRANSITION_MATRIX", nullable = false, insertable = false, updatable = false, length = 10)
private String ID_TRANSITION_MATRIX;


@Basic
@Column(name = "REFERENCE", nullable = true, insertable = true, updatable = true, precision = 0)
private Integer reference;}


And here I try to persist the parent table which is supposed to persist also the child table but the Id is not generated !

MyLibrarySabriEntity Entity = null;
MyLibraryTestEntity test = getMyLibraryTestEntity(matrixStartDate, matrixName); // here I get the values of my entity test (parent)
try {
transaction.begin();
for (int row = 0; row < 20; row++) {
for (int col = 0; col < 20; col++) {
double val = cells.get(row + FIRST_ROW, col + FIRST_COL).getDoubleValue();
Entity = getMyLibrarySabriEntity(col, row, val); // this get the values of the Entity parameters (child)
Entity.setSabriEntity(test);
test.addEntitysabri(Entity);
em.persist(test);
}
}


} catch (Exception e) {
if (transaction.isActive())
transaction.rollback();
LOGGER.warn(e.getMessage(), e);

} finally {
if (transaction.isActive())
transaction.commit();
em.close();

}

Answer

Assuming you are using JPA 2.0+

Remove this mapping completely:

@Id
@Column(name = "TRANSITION_MATRIX_ID", nullable = false, 
       insertable = true, updatable = true, length = 100)
private String TRANSITION_MATRIX_ID;

and put the @Id directly on the ManyToOne and remove the insertable and updateable attributes.

@Access(AccessType.FIELD)
@Id
@ManyToOne
@JoinColumn(name = "TRANSITION_MATRIX_ID", referencedColumnName = "ID_TRANSITION_MATRIX")
private MyLibraryTestEntity sabriEntity;

Update your ID class accordingly. Any previous reference to TRANSITION_MATRIX_ID should be replaced with a reference to sabriEntity. You are also confusing @EmbeddedId and @IdClass: Only the former would contain column definitions whereas you are using the latter approach.

public class MyLibrarySabriEntityPK implements Serializable {

    private String sabriEntity;
    private String RATING_ID_ROW;
    private String RATING_ID_COL;
}

See:

https://en.wikibooks.org/wiki/Java_Persistence/Identity_and_Sequencing#JPA_2.0