[Jpox-issues] [JPOX JIRA] Commented: (NUCDBFO-38) Lazy loading doesn't work on getter internally called by a persistence capable class.

[Costantino C. (JIRA) <web...@jp...>]

    [ http://www.datanucleus.org/servlet/jira/browse/NUCDBFO-38?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16729#action_16729 ] 

Costantino Cerbo commented on NUCDBFO-38:
-----------------------------------------

The solution of this issue is related to http://tracker.db4o.com/browse/COR-1670

> Lazy loading doesn't work on getter internally called by a persistence capable class.
> -------------------------------------------------------------------------------------
>
>                 Key: NUCDBFO-38
>                 URL: http://www.datanucleus.org/servlet/jira/browse/NUCDBFO-38
>             Project: DataNucleus DB4O
>          Issue Type: Bug
>          Components: Persistence
>    Affects Versions: 1.1.0.release
>            Reporter: Costantino Cerbo
>         Attachments: testcase.zip
>
>
> You want to persist a class with a collection, for example:
> class Person {
>     ...
>     private Collection<Address> address = new LinkedHashSet<Address>();
>     ...
> }
> The class Address use a getter in a method called by LinkedHashSet (in this case hashCode):
> class Address {
>     ...
>     public int hashCode() {
>         return getId().intValue();
>     }
>     ...
> }
> When you persist an instance of Person, whose Collection of Addresses had correctly set IDs, the following exception is thrown:
> java.lang.NullPointerException
> 	at org.datanucleus.store.db4o.Address.hashCode(Address.java:56)
> 	at java.util.HashMap.put(HashMap.java:372)
> 	at java.util.HashSet.add(HashSet.java:200)
> 	at java.util.AbstractCollection.addAll(AbstractCollection.java:305)
> 	at java.util.LinkedHashSet.<init>(LinkedHashSet.java:152)
> 	at org.datanucleus.sco.simple.LinkedHashSet.initialise(LinkedHashSet.java:81)
> The cause for this exception seems to be, that the lazy loading of the attributes doesn't happen when the method Address#getId() is invoked in Address#hashCode().
> Anyway this error occurs also when I tried to disable lazy loading with the property:
> datanucleus.cache.collections.lazy=false

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://www.datanucleus.org/servlet/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira