JDOQL : load results on connection close

If we have

Query q = pm.newQuery(myQuery);
List<Candidate> results = (List<Candidate>)q.execute();
pm.close();

then accessing of the results after close results in
org.datanucleus.exceptions.NucleusUserException: Object Manager has been 
closed
    at org.datanucleus.ObjectManagerImpl.assertIsOpen
(ObjectManagerImpl.java:3876)
    at org.datanucleus.ObjectManagerImpl.getFetchPlan
(ObjectManagerImpl.java:376)
    at org.datanucleus.store.query.Query.getFetchPlan(Query.java:497)
    at org.datanucleus.store.appengine.query.DatastoreQuery$5.apply
(DatastoreQuery.java:508)
    at org.datanucleus.store.appengine.query.DatastoreQuery$5.apply
(DatastoreQuery.java:507)
    at 
org.datanucleus.store.appengine.query.StreamingQueryResult.resolveNext
(StreamingQueryResult.java:137)

See Issue 151 for one example, but its been a common issue during the last 2 yrs of GAE/J. This is because the query knows nothing about the close of the connection that it uses. the provided patch registers a listener for connection closure (and txn commit), meaning that the QueryResult.disconnect() method is called when this happens giving the QueryResult chance to load up all remaining results.

[maxr, 2011-07-15 02:05:04]

Change looks good, but what's all the commented out code in JPQLQuery?  Are
you going to do the same thing for JPA in a follow up CL?

On Wed, Jul 13, 2011 at 10:34 PM, <andy_jefferson@yahoo.com> wrote:

> Reviewers: maxr,
>
> Description:
> If we have
>
> Query q = pm.newQuery(myQuery);
> List<Candidate> results = (List<Candidate>)q.execute();
> pm.close();
>
> then accessing of the results after close results in
> org.datanucleus.exceptions.**NucleusUserException: Object Manager has been
>
> closed
>    at org.datanucleus.**ObjectManagerImpl.assertIsOpen
> (ObjectManagerImpl.java:3876)
>    at org.datanucleus.**ObjectManagerImpl.getFetchPlan
> (ObjectManagerImpl.java:376)
>    at org.datanucleus.store.query.**Query.getFetchPlan(Query.java:**497)
>    at org.datanucleus.store.**appengine.query.**DatastoreQuery$5.apply
> (DatastoreQuery.java:508)
>    at org.datanucleus.store.**appengine.query.**DatastoreQuery$5.apply
> (DatastoreQuery.java:507)
>    at
> org.datanucleus.store.**appengine.query.**StreamingQueryResult.**
> resolveNext
> (StreamingQueryResult.java:**137)
>
> See Issue 151 for one example, but its been a common issue during the
> last 2 yrs of GAE/J. This is because the query knows nothing about the
> close of the connection that it uses. the provided patch registers a
> listener for connection closure (and txn commit), meaning that the
> QueryResult.disconnect() method is called when this happens giving the
> QueryResult chance to load up all remaining results.
>
> Please review this at
http://codereview.appspot.com/**4702045/<http://codereview.appspot.com/4702045/>
>
> Affected files:
>  src/com/google/appengine/**datanucleus/query/**DatastoreQuery.java
>  src/com/google/appengine/**datanucleus/query/JDOQLQuery.**java
>  src/com/google/appengine/**datanucleus/query/JPQLQuery.**java
>  src/com/google/appengine/**datanucleus/query/**StreamingQueryResult.java
>
>
>

[datanucleus, 2011-07-15 05:45:34]

Yes, that code in JPQLQuery is what will be needed *when the 2 failing tests are
understood*. Obviously I may have to pull refactor other things before then
depending on what it shows up, and then finally enable that code

[maxr, 2011-07-15 06:02:33]

I understand, thanks for the explanation.

Go ahead and submit.

On Fri, Jul 15, 2011 at 3:45 PM, <andy_jefferson@yahoo.com> wrote:

> Yes, that code in JPQLQuery is what will be needed *when the 2 failing
> tests are understood*. Obviously I may have to pull refactor other
> things before then depending on what it shows up, and then finally
> enable that code
>
>
>
>
http://codereview.appspot.com/**4702045/<http://codereview.appspot.com/4702045/>
>