Also, check that the PMF.getPersistenceManager() returns a non-null value.
Perhaps with the changes you've been trying you don't have the
"transactions-optional" name in the config file matching the code.
On Wed, Jan 26, 2011 at 11:00 AM, Stephen Johnson <onepagewo...@gmail.com>wrote:
> Well, you shouldn't be getting a NullPointerException if the entity is not
> found so something else is wrong. The correct exception would be
> JDOObjectNotFoundException. Are you sure the PageParameters parameters is
> not null or something else isn't null?? You don't use the 'a' variable in
> anyway in the try/catch that would cause the NullPointerException from what
> I see, so it has to be something else.
>
>
> On Wed, Jan 26, 2011 at 12:46 AM, hrbaer <herber.m...@googlemail.com>wrote:
>
>> Ok guys, even if the gql query is running I'm still not able to port
>> this logic into my java class.
>> Maybe someone could have a look at my code and correct/refer to my
>> mistake(s):
>>
>> public GuestbookDetails( final PageParameters parameters ) throws
>> StringValueConversionException {
>>
>> PersistenceManager pm = PMF.getPersistenceManager();
>> try {
>> Antwort a = pm.getObjectById( Antwort.class,
>> parameters.getAsLong( Constants.ID ) );
>> }
>> catch (NullPointerException e) {
>> System.out.println( "No entity found." );
>> }
>>
>> try {
>> Antwort a = pm.getObjectById( Antwort.class,
>> parameters.getLong( Constants.ID ) );
>> }
>> catch (NullPointerException e) {
>> System.out.println( "No entity found." );
>> }
>>
>> try {
>> Antwort a = pm.getObjectById( Antwort.class,
>> parameters.getString( Constants.ID ) );
>> }
>> catch (NullPointerException e) {
>> System.out.println( "No entity found." );
>> }
>>
>> try {
>> Antwort a = pm.getObjectById( Antwort.class,
>> parameters.getKey( Constants.ID ) );
>> }
>> catch (NullPointerException e) {
>> System.out.println( "No entity found." );
>> }
>>
>> Key k = KeyFactory.createKey( Antwort.class.getSimpleName(),
>> parameters.getLong( Constants.ID ) );
>> try {
>> Antwort a = pm.getObjectById( Antwort.class, k );
>> }
>> catch (NullPointerException e) {
>> System.out.println( "No entity found." );
>> }
>> }
>>
>> As you can imagine all querys result in the NullPointerException.
>> Parameters.getLong always returns me the value of "ID/Name" (e.g.
>> 1,2,3...).
>>
>> Apart from that I tried to fetch get my entities using the datastore
>> object. Yet without success:
>>
>> DatastoreService datastore =
>> DatastoreServiceFactory.getDatastoreService();
>> Entity entity = null;
>>
>> try {
>> entity = datastore.get( k );
>> }
>> catch (EntityNotFoundException e) {
>> System.out.println( "No entity found." );
>> }
>>
>> And last but not least with a simple query:
>>
>> Query q = new Query( Constants.ANTWORT );
>> q.addFilter( Constants.ID, FilterOperator.EQUAL,
>> parameters.getLong( Constants.ID ) );
>> PreparedQuery pq = datastore.prepare(q);
>> Entity entity = pq.asIterator().next();
>> (....)
>>
>> I think you already know the answer...
>>
>> Maybe someone is able to help me out.
>> Thanks in advance,
>>
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>>
>
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