Lazy loading problem

fjkjava · **Joined:** Thu Mar 25, 2010 11:58 am **Posts:** 4

Hi All,
I have a PO table for purchase details which contains a column for storing carrier. I store carrier id in the column and this can be null because some PO may not have carrier. I have created entity PO as shown below. When I try to display the list of PO I am getting an error javax.persistence.EntityNotFoundException: Unable to find...

When i debug my List I found if the carrier field in is null (it actually not null it ' ' single space in table and something like java_assist_12... in PO object). Then I tried to print this value in my Action class I found when i call say po.carrier.name an exception is occurring.

If I remove fetch = FetchType.LAZY then I could not get any result. I don’t understand why it is not working in either case.

Anybody have any idea. I believe foreign key in table can be null.

Code:

public class Po implements java.io.Serializable{
.
.


private Carrier carrier = new Carrier();

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumns ({
       @JoinColumn(name="LOC",nullable=true, referencedColumnName = "LOC", insertable=false, updatable=false),
        @JoinColumn(name="CARRIER",nullable=true, referencedColumnName = "CARRIER", insertable=false, updatable=false)
})
public Carrier getCarrier() {
    return this.carrier;
}

.
.
.}

Please Help
Fabian

fjkjava · **Joined:** Thu Mar 25, 2010 11:58 am **Posts:** 4

fjkjava wrote:

Hi All,
I have a PO table for purchase details which contains a column for storing carrier. I store carrier id in the column and this can be null because some PO may not have carrier. I have created entity PO as shown below. When I try to display the list of PO I am getting an error javax.persistence.EntityNotFoundException: Unable to find...

When i debug my List I found if the carrier field in is null (it actually not null it ' ' single space in table and something like java_assist_12... in PO object). Then I tried to print this value in my Action class I found when i call say po.carrier.name an exception is occurring.

If I remove fetch = FetchType.LAZY then I could not get any result. I don’t understand why it is not working in either case.

Anybody have any idea. I believe foreign key in table can be null.

Code:

public class Po implements java.io.Serializable{
.
.


private Carrier carrier = new Carrier();

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumns ({
       @JoinColumn(name="LOC",nullable=true, referencedColumnName = "LOC", insertable=false, updatable=false),
        @JoinColumn(name="CARRIER",nullable=true, referencedColumnName = "CARRIER", insertable=false, updatable=false)
})
public Carrier getCarrier() {
    return this.carrier;
}

.
.
.}

Please Help
Fabian

mmerder · **Posted:** Thu May 19, 2011 8:43 am

Is the foreign key in your table ' ' instead of null? If yes, that is the problem and it seems like you did not define a foreign key constraint on the database, did you?