[appengine-java] Re: Question: best practice to persist medium-large data?
in principle, I like to work with both, JDO and JPA. but using either
of them requires (in most cases) use of the osiv pattern, which in
turn results in using something like spring. Keeping the discussions
about request and startup performance in mind, apps on GAE shouldn't
make use of too many frameworks...
thus, I am thinking about re-designing my persistence architecture
based on JDO and Spring...
On 27 Jan., 01:40, Jeff Schnitzer j...@infohazard.org wrote:
Here's the Objectify version of what's described in the video, capable
of a photo-equivalent of million user fanout:
class Album {
�...@id Long id;
String name;}
class PhotoIndex {
�...@id Long id;
�...@parent OKeyAlbum album;
SetOKeyPhoto photos;}
class Photo {
�...@id Long id;
String caption;
String blobStoreKey;
}
If you want to ask what albums are this photo in? (equivalent to
what messages are waiting for me in the video), you query like this:
OQueryPhotoIndex query =
createQuery(PhotoIndex.class).filter(photos, photoKey);
ListOKeyAlbum keys = ofy.prepareKeysOnly(query).asList();
ListAlbum albums = ofy.get(keys);
Jeff
On Tue, Jan 26, 2010 at 4:08 PM, Duong BaTien duong.bat...@gmail.com wrote:
Hi Jeff:
I am here again and have put sometime in Objectify. Thanks for taking
pain at different design patterns. Please let the list known your effort
in the good idea #2, especially in the social graph set intersections
and union.
Duong BaTien
DBGROUPS and BudhNet
On Tue, 2010-01-26 at 14:19 -0800, Jeff Schnitzer wrote:
On Mon, Jan 25, 2010 at 11:52 PM, John Patterson jdpatter...@gmail.com
wrote:
This is why you configure what type of relationship is used using:
@Embed,
@Entity(PARENT), @Entity(CHILD) or @Entity(INDEPENDENT)
So you have the flexibility to choose configuration _without_ rewriting
your
code. Very important difference.
The problem is that it *isn't* as simple as just changing an
annotation. Not in appengine, at any rate. It works in the simple
case (good for demos and sample apps), but you start to notice edge
cases:
* In some representations you can add a Photo to an Album in a
transaction, in some representations you can't.
* In some representations, multiple queries are required to fetch a
fetch an Album containing a Photo.
* Each representation has a completely different query syntax.
Twig exposes the datastore Query object, which means the developer
gets the full brunt of this exposure.
I don't want to say that it isn't possible to build a system that
abstracts entities into a sophisticated object graph - clearly, we
have JDO JPA. What I'm saying is that the people who created JDO
JPA are not idiots (although I do think the creators of JDO's
annotations are aesthetically challenged). The reason JDO has all
that complexity and endless configuration and query languages and
fetch groups and proxies and detaching and whatnot is because that's
what you need to abstract an arbitrary entity graph.
Currently the first type of representation is not an option. I do want
to
add this as it makes very large collections that change often much more
efficient. When it is added you could reconfigure your data schema by
changing a single annotation. Such a change in Objectify would require
the
developer to rewrite their entire data layer
You can never just reconfigure your data schema with a single
annotation, both for the reasons above and because you probably have
real-world data to migrate. And real-world constraints demand a
particular schema!
Let's actually answer the original poster's question - how do you
model a photo album? I hope he's still listening :-)
The first question is how you should model it in the datastore? I'll
use Objectify's syntax here because it corresponds directly to the
datastore representation.
Actually, let's start by describing how you SHOULDN'T model a photo album.
-
BAD IDEA #1:
class Album {
@Id Long id;
String name;
ListOKeyPhoto photos;
}
class Photo {
@Id Long id;
String caption;
String blobStoreKey; // key to GAE's blobstore
}
Fetching photos in an album (again, Objectify syntax but equivalent to
the datastore operation) is:
ListPhoto fetched = ofy.get(album.photos);
There are two reasons why this is a bad idea:
1) You now have a hard limit of 5,000 photos per album, established by
GAE.
2) Every time you load an Album, you must load the entire set of
Photo keys. Want to generate a list of Album names? You have to load
all that key data, orders of mangitude more data than what you want.
-
BAD IDEA #2:
class Album {
@Id Long id;
String name;
}
class Photo {
@Id Long id;
@Parent OKeyAlbum album;
String caption;
String blobStoreKey;
}
This stores the Photo with the Album
Re: [appengine-java] Can't run the Java version of GAE.
Cristian Nicanor Babula wrote: It looks like the exception is thrown when the socket calls bind(). Isn't that you have the port 8080 already in use? No service is listed as using that port. There has been no problem using the Python version of GAE: it can use port 8080 with no problems, and appcfg.py seems to work perfectly. This problem has only appeared when I tried to use the Java version. (Also, maybe unrelated: If I try t use GIJ as the Java interpreter, it throws an UnsupportedOperationException when trying to append to an AbstractList.) -- Guillermo O. «Tordek» Freschi. Programador, Escritor, Genio Maligno. http://tordek.com.ar :: http://twitter.com/tordek http://www.arcanopedia.com.ar - Juegos de Rol en Argentina -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Google Accounts Java API and Google Apps
1. The UserService createLoginURL method accepts a authDomain String parameter, documented as authentication domain to use. What does this mean, what domain? Can I set it to any Google Apps domain so that a user from that domain can sign in? And what does For trusted apps only from the method's documentation, mean ? What is a trusted app? 2. Basically, can I use the UserService to sign in my application any user from any Google Apps domain ? -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] java.lang.NoClassDefFoundError: Could not initialize class org.datanucleus.store.appengine.DatastoreFieldManager
Hello, 7 hours after last deploy of my application I got the following exception: java.lang.NoClassDefFoundError: Could not initialize class org.datanucleus.store.appengine.DatastoreFieldManager at org.datanucleus.store.appengine.query.DatastoreQuery$3.fetchFields(DatastoreQuery.java:511) at org.datanucleus.state.JDOStateManagerImpl.loadFieldValues(JDOStateManagerImpl.java:841) at org.datanucleus.state.JDOStateManagerImpl.initialiseForHollowAppId(JDOStateManagerImpl.java:284) at org.datanucleus.state.StateManagerFactory.newStateManagerForHollowPopulatedAppId(StateManagerFactory.java:116) at org.datanucleus.ObjectManagerImpl.findObjectUsingAID(ObjectManagerImpl.java:2117) at org.datanucleus.store.appengine.query.DatastoreQuery.entityToPojo(DatastoreQuery.java:522) at org.datanucleus.store.appengine.query.DatastoreQuery.entityToPojo(DatastoreQuery.java:490) at org.datanucleus.store.appengine.query.DatastoreQuery.access$300(DatastoreQuery.java:108) at org.datanucleus.store.appengine.query.DatastoreQuery$6.apply(DatastoreQuery.java:604) at org.datanucleus.store.appengine.query.DatastoreQuery$6.apply(DatastoreQuery.java:596) at org.datanucleus.store.appengine.query.LazyResult.resolveNext(LazyResult.java:94) at org.datanucleus.store.appengine.query.LazyResult.resolveAll(LazyResult.java:116) at org.datanucleus.store.appengine.query.LazyResult.size(LazyResult.java:110) at org.datanucleus.store.appengine.query.StreamingQueryResult.size(StreamingQueryResult.java:124) at com.evo.adm.contract.server.ContractDaoJdo.findAll(ContractDaoJdo.java:140) at com.evo.adm.contract.server.ContractServiceImpl.findAll(ContractServiceImpl.java:250) at com.evo.adm.contract.server.ContractServiceImpl$$EnhancerByGuice$$815fbed1.CGLIB$findAll$12(generated) at com.evo.adm.contract.server.ContractServiceImpl$$EnhancerByGuice$$815fbed1$$FastClassByGuice$$da19b7a9.invoke(generated) at com.google.inject.internal.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) at com.google.inject.internal.ProxyFactory$1.intercept(ProxyFactory.java:48) Does anyone have an idea what is causing it ? Regards, Miroslav -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Quick question regarding List Order
A List follows the contract of java.util.List, hence obviously ordering should be preserved. Whether it is JDO or JPA, the whole point of transparent persistence - people shouldn't need to know anything about the persistence process, just use their objects as normal. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Question: best practice to persist medium-large data?
On 27 Jan 2010, at 05:19, Jeff Schnitzer wrote: although I do think the creators of JDO's annotations are aesthetically challenged). Ha ha fair enough. Sorry can't respond more just yet as Im out the door to Koh Phangan until Monday! I think its a good thing to have abstractions at different levels - thats why iBatis and Hibernate both thrive in the same domain. Higher level / lower level, more work / less work. Horses for courses. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Question about server side security
I would like to develop an App that lets my Google Apps domain users update their phone numbers for their domain Profiles. My problem is that only a domain admin can access the Profiles API. The flow would go something like: user signs in by GAE Apps domain user service. On load RPC transfers user name to servlet which uses Profiles API and hard coded domain admin account to pull user phone numbers. It does not do much so there is not alot of risk except the domain admin account credentials stored on the server side. That should not be accessible but I am concerned. Any ideas on a better way to do this or maybe there is no reason for concern? -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Google Accounts Java API and Google Apps
When you create the App on GAE it asks if you want it to be only for a Google Apps domain. This would only be for the Apps domain account you are logged into GAE with. The code does not have to be specific for the domain as the GAE userservice will know to send the sign in to the domain's auth page not gmail. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Bad jpeg compression
I noticed that the compression of images scaled by the image service is very low. The resulting image size is factors higher then it would be with reasonable jpeg compression settings. Since Google Java does not support any of the AWT classes it is very hard to find a workaround. There is a feature request to add an additional quality parameter to the image service under http://code.google.com/p/googleappengine/issues/detail?id=2410 My questions are: 1) Does anybody know a workaround (e.g. alternative jpeg encoding library) that works on appengine? 2) Is there a time frame when (if ever) this limitation is going to be fixed? PS: If you also suffer from that issue, you could give it a vote on the URL above. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] SMS Facility
There's no APIs natively for SMS. However, many mobile service providers have email gateways for SMS. Here's a quick list on Wikipedia: http://en.wikipedia.org/wiki/List_of_carriers_providing_SMS_transit http://en.wikipedia.org/wiki/List_of_carriers_providing_SMS_transitMy experience has been that some of these are a bit out of date and don't always seem to deliver in a timely manner. There are other service providers that interface directly with the carriers, however, as far as I know most of these are not free but pay per message services. These are ideal if you are planning on large one-to-many messaging campaigns: http://www.google.com/search?hl=enrlz=1C1CHMA_enUS360US360q=sms+gatewayaq=faql=aqi=g10oq= On Tue, Jan 26, 2010 at 5:53 AM, Avis developer sivaram.subb...@gmail.comwrote: Hi , Thanks for seeing to this. Is there any messaging facility in google AppEngine for Java. Is it possible to send a message to a mobile from a servlet in our application deployed here. Pls reply . Thx too. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: vs-accounting.appspot.com - datastore viewer error
What does you local indexes file look like? Can you post the indexes listed in your production admin console? On Tue, Jan 26, 2010 at 11:24 PM, aswath satrasala aswath.satras...@gmail.com wrote: Hello GAE team, Further observations made while testing the app. I am not able to write entities to the datastore. Upon examining the logs, I found the following error. com.veersoft.action.CreateTenantAction doCreate: com.google.appengine.api.datastore.DatastoreNeedIndexException: no matching index found.. datastore-index kind=SecurityGroup ancestor=true source=manual property name=secGrpList_INTEGER_IDX direction=asc/ /datastore-index The application is fine on the local develpment server. -Aswath On Tue, Jan 26, 2010 at 8:51 PM, aswath satrasala aswath.satras...@gmail.com wrote: Hello, My app-id is vs-accounting. I login into appengine.google.com. I choose the above application. Then I click on the datastore viewer. I get the error Server Error A server error has occurred. Return to Applications screen » https://appengine.google.com/ -Aswath -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] JDO - GWT - JUNIT testing examples
I'm no expert on how to unit test GWT, but in terms of testing the server, for a unit test it probably is a better idea to simply test the servlet. I've heard HtmlUnit is pretty good for this. Here's a guide for setting up JUnit to work with the datastore: http://code.google.com/appengine/docs/java/howto/unittesting.html On Tue, Jan 26, 2010 at 7:19 AM, aswath satrasala aswath.satras...@gmail.com wrote: Hi, I am using GWT and JDO to write a simple create and list Employee application. I got this working using TransferObjects . How to test the GWT asysnc calls with local datastore using Junit. -Aswath -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] 30 seconds
What's Camel? This is the only thing I was able to find on Google: http://camel.apache.org/python.html On Tue, Jan 26, 2010 at 9:40 PM, elwis elwest...@gmail.com wrote: Hi all, I'm playing around with the Appengine and thought about using it as an integration platform with Camel in the middle. However, one thing concerns me. If I'm right, my integration flow will need to be finished during this 30s that's mentioned or be killed off? 30s might not be enough if there are a lot of traffic and advanced conversions between formats. Regards Stefan -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: how to add field to entity
I think you can also use the java transient keyword to tell JDO/JPA to not persist it. Andrei wrote: Ok, i forgot to put @NotPersistent On Jan 26, 1:15 pm, Andrei gml...@gmail.com wrote: Thanks, i'll try What i do not understand, this value is not stored in db On Jan 26, 1:06 pm, John Patterson jdpatter...@gmail.com wrote: You could try using Boolean instead of boolean. On 27 Jan 2010, at 00:48, Andrei wrote: I have entity that is already stored in db I added boolean field that i do not want to store in db, so it's not marked as @Persistent When retrieve existing entity from db i get exception java.lang.NullPointerException: Datastore entity with kind Data and key Data(mykey) has a null property named needsUpdate. This property is mapped to com.foo.Data.needsUpdate, which cannot accept null values. What did i do wrong? -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com . To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com . For more options, visit this group athttp://groups.google.com/group/google-appengine-java?hl=en . -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Not allowed to access system class loader.
Is this preventing your task from running? This is generally a harmless exception. Here's another thread on the subject, though your stack trace is a bit different: http://groups.google.com/group/google-appengine-java/browse_thread/thread/e01814b8ceaf3e59/b340b4de766e09fb?lnk=gstq=FinalizableReferenceQueue+app+engine#b340b4de766e09fb On Tue, Jan 26, 2010 at 5:02 PM, ravi guntuku ravikumar.gunt...@gmail.comwrote: A simple servlet which reads some data from a table - and query analytics service and store data in another table. When i run this servlet from browser it works (always). I have scheduled this servlet to run as cron job and it is not working at all. And i see the below exception in App engine logs. 01-26 04:36PM 45.184 com.google.appengine.repackaged.com.google.common.base.FinalizableReferenceQueue $SystemLoader loadFinalizer: Not allowed to access system class loader. I 01-26 04:36PM 45.197 com.google.appengine.repackaged.com.google.common.base.internal.Finalizer getInheritableThreadLocalsField: Couldn't access Thread.inheritableThreadLocals. Reference finalizer threads will inherit thread local values. I 01-26 04:36PM 45.201 com.google.appengine.repackaged.com.google.common.base.FinalizableReferenceQueue init: Failed to start reference finalizer thread. Reference cleanup will only occur when new references are created. java.lang.reflect.InvocationTargetException at com.google.appengine.runtime.Request.process-51100059fa394f2b (Request.java) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Method.java:42) at com.google.appengine.repackaged.com.google.common.base.FinalizableReferenceQueue.init (FinalizableReferenceQueue.java:124) at com.google.appengine.repackaged.com.google.common.labs.misc.InterningPools $WeakInterningPool.clinit(InterningPools.java:104) at com.google.appengine.repackaged.com.google.common.labs.misc.InterningPools.newWeakInterningPool (InterningPools.java:48) at com.google.appengine.repackaged.com.google.io.protocol.ProtocolSupport.clinit (ProtocolSupport.java:55) at com.google.apphosting.api.DatastorePb$Query.init (DatastorePb.java:1072) at com.google.apphosting.api.DatastorePb$Query$1.init (DatastorePb.java:2529) at com.google.apphosting.api.DatastorePb$Query.clinit (DatastorePb.java:2529) at com.google.appengine.api.datastore.QueryTranslator.convertToPb (QueryTranslator.java:28) at com.google.appengine.api.datastore.DatastoreServiceImpl $PreparedQueryImpl.convertToPb(DatastoreServiceImpl.java:424) at com.google.appengine.api.datastore.DatastoreServiceImpl $PreparedQueryImpl.runQuery(DatastoreServiceImpl.java:384) at com.google.appengine.api.datastore.DatastoreServiceImpl $PreparedQueryImpl.asQueryResultIterator(DatastoreServiceImpl.java: 358) at com.google.appengine.api.datastore.DatastoreServiceImpl $PreparedQueryImpl$2.iterator(DatastoreServiceImpl.java:338) at com.google.appengine.api.datastore.DatastoreServiceImpl $PreparedQueryImpl$2.iterator(DatastoreServiceImpl.java:336) at org.datanucleus.store.appengine.query.RuntimeExceptionWrappingIterable.iterator (RuntimeExceptionWrappingIterable.java:42) at org.datanucleus.store.appengine.query.LazyResult.init (LazyResult.java:67) at org.datanucleus.store.appengine.query.StreamingQueryResult.init (StreamingQueryResult.java:63) at org.datanucleus.store.appengine.query.DatastoreQuery.newStreamingQueryResultForEntities (DatastoreQuery.java:399) at org.datanucleus.store.appengine.query.DatastoreQuery.wrapEntityQueryResult (DatastoreQuery.java:372) at org.datanucleus.store.appengine.query.DatastoreQuery.fulfillEntityQuery (DatastoreQuery.java:364) at org.datanucleus.store.appengine.query.DatastoreQuery.executeQuery (DatastoreQuery.java:265) at org.datanucleus.store.appengine.query.DatastoreQuery.performExecute (DatastoreQuery.java:228) at org.datanucleus.store.appengine.query.JDOQLQuery.performExecute (JDOQLQuery.java:85) at org.datanucleus.store.query.Query.executeQuery(Query.java:1489) at org.datanucleus.store.query.Query.executeWithArray(Query.java: 1371) at org.datanucleus.store.query.Query.execute(Query.java:1344) at org.datanucleus.jdo.JDOQuery.execute(JDOQuery.java:221) at sample.data.SaveGoogleData.saveData(SaveGoogleData.java:53) at sample.controller.DataStoreServlet.doGet(DataStoreServlet.java:21) at javax.servlet.http.HttpServlet.service(HttpServlet.java:693) at javax.servlet.http.HttpServlet.service(HttpServlet.java:806) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java: 487)
Re: [appengine-java] Re: One-to-many querying for a child instance
Do you need a colon in front of nameParam?
query.setFilter(name == :nameParam);
Sydney wrote:
The query returns no result.
ApiProxy.setEnvironmentForCurrentThread(new TestEnvironment
());
ApiProxy.setDelegate(new ApiProxyLocalImpl(new File(.))
{
});
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
PersistenceManagerFactory pmf =
JDOHelper.getPersistenceManagerFactory(transactions-optional);
PersistenceManager pm = pmf.getPersistenceManager();
Transaction tx = pm.currentTransaction();
try {
tx.begin();
pm.makePersistent(a);
tx.commit();
} finally {
if (tx.isActive()) {
tx.rollback();
}
}
System.out.println(a.getKey());
A ap = pm.getObjectById(A.class, A);
System.out.println(ap.getKey());
Query query = pm.newQuery(B.class);
query.setFilter(name == nameParam);
query.declareParameters(String nameParam);
ListB rs = (ListB) query.execute(B);
System.out.println(rs.size());
On Jan 23, 12:20 am, John Patterson jdpatter...@gmail.com wrote:
Execute a query on the name property of B rather than loading it by
key. If the name is unique the result should only contain one B.
On 23 Jan 2010, at 11:41,Sydneywrote:
I have a one to many relationship. There is a problem in the way I
query for a B object. I was wondering what is the best way (most
efficient) to do that.
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
pm.makePersistent(a); // it's done inside a transaction
A ap = pm.getObjectById(A.class, A); // FINE
B bp = pm.getObjectById(B.class, B); // NOT FOUND Exception
I guess B is not found because the real key is not B but B + A key.
How do you get the B object when you don't know nothing about A?
public class A {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
@Extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
@Persistent
@Extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
@Persistent(mappedBy = a)
private ListB bs;
public A(String name) {
this.name = name;
bs = new ArrayListB();
}
... Getter/Setter
}
@PersistenceCapable(identityType =
javax.jdo.annotations.IdentityType.APPLICATION)
public class B {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
@Extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
@Persistent
@Extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
@Persistent
private A a;
public B(String name) {
this.name = name;
}
... Getter/Setter
}
--
You received this message because you are subscribed to the Google
Groups Google App Engine for Java group.
To post to this group, send email to google-appengine-java@googlegroups.com
.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com
.
For more options, visit this group
athttp://groups.google.com/group/google-appengine-java?hl=en
.
--
You received this message because you are subscribed to the Google Groups Google
App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Trouble with Consuming Web Service from a Background Thread.
Hi,
I am trying to consume a REStful web service from my web application
that is deployed under the App Engine.
I am using the Jersey framework in order to make the web service call
and I followed the steps outlined in this tutorial:
http://blogs.sun.com/enterprisetechtips/entry/consuming_restful_web_services_with.
I need to call this web service periodically and gather data which is
then entered into the App Engine data store.
The following is what I do:
In have an instance of javax.servlet.ServletContextListener which is
called upon the application start up. It spins up a background thread
by calling the start() method on an instance of a class that extends
java.lang.Thread. Then, inside the run() method of the class that
extends Thread, I have the code for calling the web service. Here's
that code. Below, the classes Client, ClientConfig,
DefaultClientConfig and WebResource are all from the Jersey framework.
try
{
ClientConfig config = new DefaultClientConfig ();
Client client = Client.create (config);
WebResource webResource = client.resource
(http://www.iobridge.com/
interface/feed/FD_0BosKdymNbB3LyiFYUVI);
String response = webResource.accept
(application/json).get
(String.class);
}
catch (Exception ex)
{
}
Here's my problem:
When I execute this code on a background thread, I get a
NullPointerException. However, if I execute it, say, in the
ServletContextListener's contextInitialized() method, then it works
fine. What is causing this to happen?
I repeated this experiment by trying to make an HTTP GET request using
plain old Java classes in the java.net package, that is, using the URL
and URLConnection classes.
URL url = new URL (http://www.iobridge.com/interface/feed/
FD_0BosKdymNbB3LyiFYUVI);
URLConnection connection = url.openConnection ();
connection.setDoOutput (true);
connection.setRequestProperty (Content-Type, application/json);
BufferedReader in = new BufferedReader (new InputStreamReader
(connection.getInputStream ()));
Here too, the code does not work on a background thread but works OK
elsewhere.
Is the usage of background threads the primary cause here?
Thanks,
Viji
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] User authentication
Hi, Am new to GAE. I want to build an application on GAE that stores data from multiple companies. I would like to get advice on what would be the best approach .. 1) To host the application in different domains - one for each company? 2) to host the application in one domain and use the authentication/authorization provided in GAE to show the relevant data to the users? A gmail account may not have company information for a person.. 3) build the authentication/authorization mechanism into my application? Kindly advice. Thanks! Sree -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Can't get JUnit to test making a JDO object persistent
I originally posted this on General discussion, not realizing there is
a Java specific group, so I am sorry for the redundancy:
I have gotten the basic setup recommended in the docs. I am able to
query the database successfully but as soon as I attempt to persists a
JDO object I get a can't find annotations error. The code is simply:
public class UserTestCase extends LocalDatastoreTestCase {
public void testDatesBeingSetOnCreate() {
User user = new User(w...@thebunkers.com, mypassword);
//DatastoreServiceFactory.getDatastoreService().put(user);
PersistenceManager manager = newPersistenceManager();
manager.makePersistent(user);
manager.close();
Query query = new Query(User.class.getSimpleName());
assertEquals(1, DatastoreServiceFactory.getDatastoreService
().prepare(query).countEntities());
}
}
The error occurs at the makePersistent call. If I comment it out the
test runs fine except of course there is no user on the assert line.
The error is:
org.datanucleus.jdo.exceptions.NoPersistenceInformationException: The
class The class com.sootra.shared.User is required to be
persistable yet no Meta-Data/Annotations can be found for this class.
Please check that the Meta-Data/annotations is defined in a valid file
location. is required to be persistable yet no Meta-Data can be found
for this class. Please check that the Meta-Data is defined in a valid
file location for JDO.
I am able to run the create user fine when running the app locally, as
well as uploading it to app engine. So the code is fine, but I am
unable to get JUnit test to recognize where the MetaData is being
created by the enhancer.
Has anyone successfully gotten this to run in Eclipse. I am guessing
that I am missing some classpath setting or meta information, but can
not find any references anywhere on the net yet.
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Can't operate on multiple entity groups when reading
Getting error message
NestedThrowablesStackTrace:
java.lang.IllegalArgumentException: can't operate on multiple entity
groups in a single transaction. found both Element {
type: Book
id: 2
}
and Element {
type: Book
id: 4
}
fails on the line
BookService : book.getPage(); as each book is in a separate
entity group
but why does it not fail on
Book book = bookmark.getBook();? as each bookmark is also in a
separate entity group.
@Test
public void listTwoBooksBySingleUser() {
User user = new User(jo...@vegas.com, test auth domain,
1234);
userService.save(user);
Book book1 = new Book();
book1.setTitle(test book title 1);
bookService.save(book1);
Book book2 = new Book();
book2.setTitle(test book title 2);
bookService.save(book2);
bookService.createBookmarkForUser(book1, user);
bookService.createBookmarkForUser(book2, user);
ListBook books = bookService.listByUser(user);
assertEquals(2,books.size());
assertEquals(test book title 1, books.get(0).getTitle());
assertEquals(test book title 2, books.get(1).getTitle());
}
public class BookService {
public ListBook listByUser(User user) {
Query query = em.createQuery(SELECT bm FROM
+Bookmark.class.getName
()+ bm WHERE bm.userKeys = :userKey);
query.setParameter(userKey, user.getKey());
ListBookmark bookmarks = query.getResultList();
ListBook books = new ArrayListBook();
for (Bookmark bookmark : bookmarks) {
Book book = bookmark.getBook();
book.getPage();
books.add(book);
}
return books;
}
}
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Question: best practice to persist medium-large data?
On Wed, Jan 27, 2010 at 2:44 AM, datanucleus andy_jeffer...@yahoo.com wrote:
Exposing Key to a user is not (in my opinion) a requirement for
*providing* a JDO impl on GAE/J. Other datastores have their own
internal id and we don't expose theirs (e.g db4o).
...
And, of course, all of that (endless) configuration is optional. There
is very little that is mandatory, like declaring what class(es) can be
persisted. Evidently, at some point, you're going to actually define
*what* is aesthetically displeasing about JDO annotations, and you
could do that with reference to JPA annotations too (where you'll find
many many more annotations, and with delightfully RDBMS specific names
too) :-) Such annotations obviously had to provide backwards
compatibility naming with JDO 1.0 and JDO 2.0 specs, and as the saying
goes, if you think you can do better ...
Going back to the original poster's request, would you like to provide
JDO (on GAE/J) equivalents of the annotated entities that described in
BAD IDEA #1, BAD IDEA #2, and GOOD IDEA? That is:
1) A one-to-many relationship stored as a Photo key array in the Album entity
2) A one-to-many relationship stored as an Album key in the Photo's key parent
3) A one-to-many relationship stored as an Album key property in a Photo entity
(The BAD IDEAS are bad for a photo album app, but they are perfectly
good ideas in other apps so they're quite relevant to this
discussion).
Aesthetics are of course subjective, but you're handicapped right out
of the gate when the first few lines of code look like this (taken
from the first full example class of Defining Data Classes in the
GAE/J docs):
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class Employee {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
...
I'm sure there are perfectly good historical reasons for why things
are the way they are, but nevertheless the accumulated load of
oddly-named things and inconsistent placement makes the learning curve
excruciating. Why do I define the identity type in these other
annotations and not in @PrimaryKey??
JPA is a little better with @Entity and @Id, but you will have a hard
time finding someone that wouldn't rather read and type the Objectify
version:
public class Employee {
@Id Long id;
(@Entity is unnecessary)
Jeff
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Trouble with Consuming Web Service from a Background Thread.
You won't be able to create a thread in App Engine. It's strange that you're
getting a NullPointerException, however. This is documented here:
http://code.google.com/appengine/docs/java/overview.html
On Wed, Jan 27, 2010 at 12:53 PM, Viji Sarathy viji.sara...@gmail.comwrote:
Hi,
I am trying to consume a REStful web service from my web application
that is deployed under the App Engine.
I am using the Jersey framework in order to make the web service call
and I followed the steps outlined in this tutorial:
http://blogs.sun.com/enterprisetechtips/entry/consuming_restful_web_services_with
.
I need to call this web service periodically and gather data which is
then entered into the App Engine data store.
The following is what I do:
In have an instance of javax.servlet.ServletContextListener which is
called upon the application start up. It spins up a background thread
by calling the start() method on an instance of a class that extends
java.lang.Thread. Then, inside the run() method of the class that
extends Thread, I have the code for calling the web service. Here's
that code. Below, the classes Client, ClientConfig,
DefaultClientConfig and WebResource are all from the Jersey framework.
try
{
ClientConfig config = new DefaultClientConfig ();
Client client = Client.create (config);
WebResource webResource = client.resource (
http://www.iobridge.com/
interface/feed/FD_0BosKdymNbB3LyiFYUVI);
String response = webResource.accept
(application/json).get
(String.class);
}
catch (Exception ex)
{
}
Here's my problem:
When I execute this code on a background thread, I get a
NullPointerException. However, if I execute it, say, in the
ServletContextListener's contextInitialized() method, then it works
fine. What is causing this to happen?
I repeated this experiment by trying to make an HTTP GET request using
plain old Java classes in the java.net package, that is, using the URL
and URLConnection classes.
URL url = new URL (http://www.iobridge.com/interface/feed/
FD_0BosKdymNbB3LyiFYUVI);
URLConnection connection = url.openConnection ();
connection.setDoOutput (true);
connection.setRequestProperty (Content-Type, application/json);
BufferedReader in = new BufferedReader (new InputStreamReader
(connection.getInputStream ()));
Here too, the code does not work on a background thread but works OK
elsewhere.
Is the usage of background threads the primary cause here?
Thanks,
Viji
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to
google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com
.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
--
Ikai Lan
Developer Programs Engineer, Google App Engine
http://googleappengine.blogspot.com | http://twitter.com/app_engine
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Can't get JUnit to test making a JDO object persistent
Also turned on logging of the Datanucleus to the finest level and am getting the following: Jan 27, 2010 2:00:08 PM org.datanucleus.PersistenceConfiguration setProperty INFO: Property datanucleus.rdbms.sql.allowAllSQLStatements unknown - will be ignored Jan 27, 2010 2:00:08 PM org.datanucleus.PersistenceConfiguration setProperty INFO: Property datanucleus.rdbms.stringDefaultLength unknown - will be ignored Jan 27, 2010 2:00:08 PM org.datanucleus.PersistenceConfiguration setProperty INFO: Property datanucleus.appengine.autoCreateDatastoreTxns unknown - will be ignored Jan 27, 2010 2:00:08 PM org.datanucleus.ObjectManagerFactoryImpl logConfiguration INFO: = Persistence Configuration === Jan 27, 2010 2:00:08 PM org.datanucleus.ObjectManagerFactoryImpl logConfiguration INFO: DataNucleus Persistence Factory - Vendor: DataNucleus Version: 1.1.5 Jan 27, 2010 2:00:08 PM org.datanucleus.ObjectManagerFactoryImpl logConfiguration INFO: DataNucleus Persistence Factory initialised for datastore URL=appengine driver= userName= Jan 27, 2010 2:00:08 PM org.datanucleus.ObjectManagerFactoryImpl logConfiguration INFO: === Jan 27, 2010 2:00:08 PM org.datanucleus.PersistenceConfiguration setProperty INFO: Property datanucleus.query.cached unknown - will be ignored Jan 27, 2010 2:00:08 PM org.datanucleus.jdo.metadata.JDOMetaDataManager init INFO: Registering listener for metadata initialisation Jan 27, 2010 2:00:08 PM org.datanucleus.jdo.metadata.JDOMetaDataManager $MetaDataRegisterClassListener registerClass INFO: Listener found initialisation for persistable class com.sootra.shared.User Jan 27, 2010 2:00:08 PM org.datanucleus.jdo.metadata.JDOAnnotationReader processClassAnnotations INFO: Class com.sootra.shared.User has been specified with JDO annotations so using those. Jan 27, 2010 2:00:08 PM org.datanucleus.store.appengine.MetaDataValidator validate INFO: Performing appengine-specific metadata validation for com.sootra.shared.User Jan 27, 2010 2:00:08 PM org.datanucleus.store.appengine.MetaDataValidator validate INFO: Finished performing appengine-specific metadata validation for com.sootra.shared.User Jan 27, 2010 2:00:08 PM org.datanucleus.store.StoreDataManager registerStoreData INFO: Managing Persistence of Class : com.sootra.shared.User [Table : (none), InheritanceStrategy : subclass-table] Jan 27, 2010 2:00:08 PM org.datanucleus.store.StoreDataManager registerStoreData INFO: Managing Persistence of Class : com.sootra.shared.User [Table : (none), InheritanceStrategy : subclass-table] So it seems to be running the metadata validation but then can't find the enhanced information??? -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] problem with documentation
When I'm learning something new one of the things that slows me down is poor documentation. I think the app engine java documentation Storing Data could be improved if it used consistent terminology in the area of entity groups, which is a crucial part of understanding how the data store works. Sometimes the documentation uses the terms owned and unowned relationships, sometimes the terms parent and child. I'm thinking that the owned and unowned terms aren't the best choice since you can't use them to say anything about a child. To my way of thinking an owned relationship is a parented relationship. But then you can't say that an unowned relationship is an unparented relationship since the owned entity could have a parent. Perhaps you could call it a nonparented relationship? Or maybe a nonparenting relationship? Overall I much prefer the terms parent and child; the data is stored with a tree structure and parent and child are the natural terms when talking about trees. I also think that if the terms parent and child were used instead of owned (and unowned) that it could help people more quickly understand that the structure in the data store is a tree. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Can't get JUnit to test making a JDO object persistent
Here they are:
/**
* Convenience method: gets a new PersistenceManager
*/
public PersistenceManager newPersistenceManager() {
return this.getPersistenceManagerFactory()
.getPersistenceManager();
}
/**
* Gets the PersistenceManagerFactory that was created by
* this Initializer.
*/
public PersistenceManagerFactory getPersistenceManagerFactory() {
if (pmf == null) {
Logger.getLogger(DataNucleus.JDO).setLevel(Level.FINEST);
Logger.getLogger(DataNucleus.JPA).setLevel(Level.FINEST);
Logger.getLogger(DataNucleus.Persistence).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Query).setLevel(Level.FINEST);
Logger.getLogger(DataNucleus.Lifecycle).setLevel(Level.FINEST);
Logger.getLogger(DataNucleus.Reachability).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Cache).setLevel(Level.FINEST);
Logger.getLogger(DataNucleus.ClassLoading).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.MetaData).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Management).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.General).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Connection).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.JCA).setLevel(Level.FINEST);
Logger.getLogger(DataNucleus.Transaction).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Plugin).setLevel(Level.OFF);
Logger.getLogger(DataNucleus.ValueGeneration).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Datastore).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Datastore.Schema).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Datastore.Persist).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Datastore.Retrieve).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Datastore.Native).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.Enhancer).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.SchemaTool).setLevel
(Level.FINEST);
Logger.getLogger(DataNucleus.IDE).setLevel(Level.FINEST);
Properties newProperties = new Properties();
newProperties.put(javax.jdo.PersistenceManagerFactoryClass,
org.datanucleus.store.appengine.jdo.DatastoreJDOPersistenceManagerFactory);
newProperties.put
(javax.jdo.option.ConnectionURL,appengine);
newProperties.put(javax.jdo.option.NontransactionalRead,
true);
newProperties.put(javax.jdo.option.NontransactionalWrite,
true);
newProperties.put(javax.jdo.option.RetainValues,true);
newProperties.put
(datanucleus.appengine.autoCreateDatastoreTxns,true);
pmf = JDOHelper.getPersistenceManagerFactory(newProperties);
}
return pmf;
}
@PersistenceCapable(identityType = IdentityType.APPLICATION)
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)
public class User implements PersistHooks {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
@Persistent
private Email email;
@Persistent
private String user_type;
@Persistent
private String password;
@Persistent
private Date create_time;
@Persistent
private Date create_date;
@Persistent
private Date update_time;
@Persistent
private Date update_date;
@SuppressWarnings(deprecation)
public void beforeSave() {
if (this.create_date == null) {
this.create_time = new Date();
this.create_date = new Date(create_time.getYear(),
create_time.getMonth(), create_time.getDate());
}
this.update_time = new Date();
this.update_date = new Date(update_time.getYear(),
update_time.getMonth(), update_time.getDate());
}
public void afterLoad() {}
public User(String email, String password) {
this.email = new Email(email);
this.password = password;
}
public User() {
}
public Key getKey() {
return key;
}
public void setKey(Key key) {
this.key = key;
}
public Email getEmail() {
return email;
}
public void setEmail(Email email) {
this.email = email;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Date getCreate_time() {
return create_time;
}
public void setCreate_time(Date createTime) {
create_time = createTime;
}
public Date getCreate_date() {
return create_date;
}
public
[appengine-java] Re: Question: best practice to persist medium-large data?
Going back to the original poster's request, would you like to provide
JDO (on GAE/J) equivalents of the annotated entities that described in
BAD IDEA #1, BAD IDEA #2, and GOOD IDEA? That is:
I only represent JDO, as a spec, not how GAE/J have implemented it.
The docs for that are provided in the JDO spec and on the DataNucleus
website. I fail to see anything controversial in how they are
represented in those places. I've already made my feelings well enough
known on exposing environment specific classes into user space
Aesthetics are of course subjective, but you're handicapped right out
of the gate when the first few lines of code look like this (taken
from the first full example class of Defining Data Classes in the
GAE/J docs):
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class Employee {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
So how GAE/J present them ? Not how DataNucleus present them in our
docs then?
No need to specify identityType=IdentityType.APPLICATION since the
user provides a primary key. You need an annotation of some form to
say your class is persistent, and one to say that this is a PK field,
and it has a generated value.
You define the valueStrategy not in @PrimaryKey because in JDO you can
generate a value into *any* field not just in a PK. JDO provides
flexibility in that respect, something to be pleased about.
JPA is a little better with @Entity and @Id
And you forgot @GeneratedValue to get the equivalent thing, so not
really any different. So you have shorter names, but then you have an
IDE too that adds them with completion, so what difference is that?
Either way, if you think you can make some improvements and really
want to effect a standard then the Apache JDO group is waiting to hear
from you
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Getting the size of a http request?
Are there places where this isn't reliably set? In my servlet I am calling: int contentLength = request.getContentLength(); This works with the following form: form action=/content_length method=POST enctype=multipart/form-data input type=file name=somefile / input type=text name=sometext / input type=submit / /form On Mon, Jan 25, 2010 at 3:46 AM, armanuj arama...@gmail.com wrote: Hello, How can one get the byte size of a http request, esp. in the context of a Java servlet being used in the Google app. engine? Is there a way to do this where the 'Content-Length' is not set (or not reliably set) in the get/post headers? Appreciate your help in this. Thanks, Arun -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Can't get JUnit to test making a JDO object persistent
I was wrong with my initial analysis. I had assumed because a
subclass was persisting that the super class would also. When I try
and add a User I get the meta/data missing also in local environment.
I have narrowed it down to one line which triggers the problem:
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)
public class User implements PersistHooks {
when I take out the @Inheritance then it finds the meta-data for the
user class. Is this a feature or a bug??
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: One-to-many querying for a child instance
Since I declared the parameter with query.declareParameters(String
nameParam);, the colon is not valid. As expected I got an exception
org.datanucleus.store.query.QueryCompilerSyntaxException: Explicit
parameters defined for query, yet implicit parameter syntax
(:nameParam) found
On Jan 27, 4:39 pm, Rusty Wright rwright.li...@gmail.com wrote:
Do you need a colon in front of nameParam?
query.setFilter(name == :nameParam);
Sydneywrote:
The query returns no result.
ApiProxy.setEnvironmentForCurrentThread(new TestEnvironment
());
ApiProxy.setDelegate(new ApiProxyLocalImpl(new File(.))
{
});
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
PersistenceManagerFactory pmf =
JDOHelper.getPersistenceManagerFactory(transactions-optional);
PersistenceManager pm = pmf.getPersistenceManager();
Transaction tx = pm.currentTransaction();
try {
tx.begin();
pm.makePersistent(a);
tx.commit();
} finally {
if (tx.isActive()) {
tx.rollback();
}
}
System.out.println(a.getKey());
A ap = pm.getObjectById(A.class, A);
System.out.println(ap.getKey());
Query query = pm.newQuery(B.class);
query.setFilter(name == nameParam);
query.declareParameters(String nameParam);
ListB rs = (ListB) query.execute(B);
System.out.println(rs.size());
On Jan 23, 12:20 am, John Patterson jdpatter...@gmail.com wrote:
Execute a query on the name property of B rather than loading it by
key. If the name is unique the result should only contain one B.
On 23 Jan 2010, at 11:41,Sydneywrote:
I have a one to many relationship. There is a problem in the way I
query for a B object. I was wondering what is the best way (most
efficient) to do that.
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
pm.makePersistent(a); // it's done inside a transaction
A ap = pm.getObjectById(A.class, A); // FINE
B bp = pm.getObjectById(B.class, B); // NOT FOUND Exception
I guess B is not found because the real key is not B but B + A key.
How do you get the B object when you don't know nothing about A?
public class A {
�...@primarykey
�...@persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
�...@extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
�...@persistent
�...@extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
�...@persistent(mappedBy = a)
private ListB bs;
public A(String name) {
this.name = name;
bs = new ArrayListB();
}
... Getter/Setter
}
@PersistenceCapable(identityType =
javax.jdo.annotations.IdentityType.APPLICATION)
public class B {
�...@primarykey
�...@persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
�...@extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
�...@persistent
�...@extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
�...@persistent
private A a;
public B(String name) {
this.name = name;
}
... Getter/Setter
}
--
You received this message because you are subscribed to the Google
Groups Google App Engine for Java group.
To post to this group, send email to
google-appengine-java@googlegroups.com
.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com
.
For more options, visit this group
athttp://groups.google.com/group/google-appengine-java?hl=en
.
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: One-to-many querying for a child instance
I used an extent to verify that a B with a B name exists.
ExtentB e = pm.getExtent(B.class);
IteratorB it = e.iterator();
while (it.hasNext()) {
B rsb = it.next();
System.out.println(rsb.getName());
System.out.println(rsb.getKey());
}
e.closeAll();
The output:
B
agR0ZXN0chALEgFBIgFBDAsSAUIiAUIM
On Jan 27, 6:41 pm, Sydney sydney.henr...@gmail.com wrote:
Since I declared the parameter with query.declareParameters(String
nameParam);, the colon is not valid. As expected I got an exception
org.datanucleus.store.query.QueryCompilerSyntaxException: Explicit
parameters defined for query, yet implicit parameter syntax
(:nameParam) found
On Jan 27, 4:39 pm, Rusty Wright rwright.li...@gmail.com wrote:
Do you need a colon in front of nameParam?
query.setFilter(name == :nameParam);
Sydneywrote:
The query returns no result.
ApiProxy.setEnvironmentForCurrentThread(new TestEnvironment
());
ApiProxy.setDelegate(new ApiProxyLocalImpl(new File(.))
{
});
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
PersistenceManagerFactory pmf =
JDOHelper.getPersistenceManagerFactory(transactions-optional);
PersistenceManager pm = pmf.getPersistenceManager();
Transaction tx = pm.currentTransaction();
try {
tx.begin();
pm.makePersistent(a);
tx.commit();
} finally {
if (tx.isActive()) {
tx.rollback();
}
}
System.out.println(a.getKey());
A ap = pm.getObjectById(A.class, A);
System.out.println(ap.getKey());
Query query = pm.newQuery(B.class);
query.setFilter(name == nameParam);
query.declareParameters(String nameParam);
ListB rs = (ListB) query.execute(B);
System.out.println(rs.size());
On Jan 23, 12:20 am, John Patterson jdpatter...@gmail.com wrote:
Execute a query on the name property of B rather than loading it by
key. If the name is unique the result should only contain one B.
On 23 Jan 2010, at 11:41,Sydneywrote:
I have a one to many relationship. There is a problem in the way I
query for a B object. I was wondering what is the best way (most
efficient) to do that.
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
pm.makePersistent(a); // it's done inside a transaction
A ap = pm.getObjectById(A.class, A); // FINE
B bp = pm.getObjectById(B.class, B); // NOT FOUND Exception
I guess B is not found because the real key is not B but B + A key.
How do you get the B object when you don't know nothing about A?
public class A {
�...@primarykey
�...@persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
�...@extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
�...@persistent
�...@extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
�...@persistent(mappedBy = a)
private ListB bs;
public A(String name) {
this.name = name;
bs = new ArrayListB();
}
... Getter/Setter
}
@PersistenceCapable(identityType =
javax.jdo.annotations.IdentityType.APPLICATION)
public class B {
�...@primarykey
�...@persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
�...@extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
�...@persistent
�...@extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
�...@persistent
private A a;
public B(String name) {
this.name = name;
}
... Getter/Setter
}
--
You received this message because you are subscribed to the Google
Groups Google App Engine for Java group.
To post to this group, send email to
google-appengine-java@googlegroups.com
.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com
.
For more options, visit this group
athttp://groups.google.com/group/google-appengine-java?hl=en
.
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Question: best practice to persist medium-large data?
Thanks Jeff.
There seems to be something at odd:
On Tue, 2010-01-26 at 16:40 -0800, Jeff Schnitzer wrote:
Here's the Objectify version of what's described in the video, capable
of a photo-equivalent of million user fanout:
class Album {
@Id Long id;
String name;
}
class PhotoIndex {
@Id Long id;
@Parent OKeyAlbum album;
SetOKeyPhoto photos;
}
class Photo {
@Id Long id;
String caption;
String blobStoreKey;
}
If you want to ask what albums are this photo in? (equivalent to
what messages are waiting for me in the video), you query like this:
OQueryPhotoIndex query =
createQuery(PhotoIndex.class).filter(photos, photoKey);
ListOKeyAlbum keys = ofy.prepareKeysOnly(query).asList();
ListAlbum albums = ofy.get(keys);
Jeff
In the above query to ask what albums are this photo in, I wonder if it
is legitimate to cast List of PhotoIndex keys with ListOKeyAlbum so
you can get a particular photoKey in a list of albums.
Using the same structure for User, MessageIndex and Message, the query
seems to ask for a list of users, a particular message is sent to?
class User {
@Id Name userId;
}
class MessageIndex {
@Id Long messageIndexId;
@Parent OKeyUser userKey;
ListOKeyMessage messageKeys;
}
class Message {
@Id Long messageId;
String ccontent;
}
To query the list of users a particular messageKey is sent to:
OQueryMessageIndex query =
ObjectifyService.createQuery(MessageIndex.class).filter(messageKeys,
messageKey);
ListOKeyUser userKeys = ofy.prepareKeysOnly(query).asList();
ListUser users = ofy.get(userKeys);
To query what messages are waiting for me:
OQueryMessageIndex query = ObjectifyService.createQuery
(MessageIndex.class).filter(userKey, meKey);
ListOKeyMessage listOfMessageKeys = ofy.prepareKeysOnly
(query).asList();
// iterate through listOfMessageKeys and each iteration, get a batch of
messages sent to meKey?
Can GQL of python be used in Objectify?
Thanks
Duong BaTien
DBGROUPS and BudhNet
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Can't get JUnit to test making a JDO object persistent
Realize that I totally misunderstood the @inheritance properties. I
was assuming that all subclasses would be store in super class, but
realize that it is the opposite. So there is no actual meta data
being generated for the user table, but all the fields are put in the
metadata for subclass.
On Jan 27, 3:40 pm, Will Bunker w...@thebunkers.com wrote:
I was wrong with my initial analysis. I had assumed because a
subclass was persisting that the super class would also. When I try
and add a User I get the meta/data missing also in local environment.
I have narrowed it down to one line which triggers the problem:
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)
public class User implements PersistHooks {
when I take out the @Inheritance then it finds the meta-data for the
user class. Is this a feature or a bug??
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Can't get JUnit to test making a JDO object persistent
I'm not entirely sure what you're doing with inheritance, but does this open
issue help?
http://code.google.com/p/datanucleus-appengine/issues/detail?id=25
On Wed, Jan 27, 2010 at 5:08 PM, Will Bunker w...@thebunkers.com wrote:
Realize that I totally misunderstood the @inheritance properties. I
was assuming that all subclasses would be store in super class, but
realize that it is the opposite. So there is no actual meta data
being generated for the user table, but all the fields are put in the
metadata for subclass.
On Jan 27, 3:40 pm, Will Bunker w...@thebunkers.com wrote:
I was wrong with my initial analysis. I had assumed because a
subclass was persisting that the super class would also. When I try
and add a User I get the meta/data missing also in local environment.
I have narrowed it down to one line which triggers the problem:
@Inheritance(strategy = InheritanceStrategy.SUBCLASS_TABLE)
public class User implements PersistHooks {
when I take out the @Inheritance then it finds the meta-data for the
user class. Is this a feature or a bug??
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to
google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com
.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
--
Ikai Lan
Developer Programs Engineer, Google App Engine
http://googleappengine.blogspot.com | http://twitter.com/app_engine
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Question: best practice to persist medium-large data?
On Wed, Jan 27, 2010 at 3:28 PM, datanucleus andy_jeffer...@yahoo.com wrote: I only represent JDO, as a spec, not how GAE/J have implemented it. The docs for that are provided in the JDO spec and on the DataNucleus website. I fail to see anything controversial in how they are represented in those places. I've already made my feelings well enough known on exposing environment specific classes into user space This response (which I have seen repeated many times on this list) is deeply unsatisfying. JDO is wonderful, the problem is just the implementation! Sounds a bit like socialism. It certainly does no good for the original poster. I think there's a problem with JDO in general - it tries to be a universal data access API, but really only gets 85% of the way there. BigTable is something different, and the old mapping annotations are (yet again) insufficient, so you need extensions like gae.unindexed and twisting the query language to support batch queries. Every time something different comes up, JDO annotations expand and now it's full of what feels like cruft. Half of DataNucleus' features don't apply to BigTable, and several significant aspects of BigTable aren't handled by JDO. I reposit my earlier question, how can you configure - in JDO - the three different one-to-many representations that BigTable supports, all of which have differing performance and transactional characteristics: 1) A one-to-many relationship stored as a Photo key array in the Album entity 2) A one-to-many relationship stored as an Album key in the Photo's key parent 3) A one-to-many relationship stored as an Album key property in a Photo entity It won't be on the DataNucleus website because these are specifically BigTable representation issues. It's not in the GAE/J docs. My guess is that at least one of these three representations requires Key manipulation by the user. And you forgot @GeneratedValue to get the equivalent thing, so not really any different. So you have shorter names, but then you have an IDE too that adds them with completion, so what difference is that? Length is irrelevant. Being able to be read and understood easily without digging through piles of documentation on three different websites is essential. In this respect, JDO is awful. Either way, if you think you can make some improvements and really want to effect a standard then the Apache JDO group is waiting to hear from you My goal is to create a simple interface that allows users to conveniently access the power of BigTable with the shortest possible learning curve. Your goal is to create a grand unified API which allows nearly any entity graph to be represented on nearly any concrete datastore. Our goals are not compatible. Jeff -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] SocialWok.com presentation qusetion on workaround on join
On Tue, Jan 26, 2010 at 5:41 PM, asianCoolz second.co...@gmail.com wrote:
DatastoreService dataSvc =...;
Query query = new Query(MessageRecipients)
.addFilter(recipients), FilterOperator.EQUAL,userid)
.addSort(date, SortDirection.DESCENDING)
.setKeysOnly(); // -- Only fetch keys!
//*** from the presentation , mentioned the above can only be done
using low level api, arent jdo/jpa can get the key only value as well
//***http://gae-java-persistence.blogspot.com/2009/10/keys-only-
queries.html
Can you post the link to the video as well as a summary of the technique
they are discussing? I've been meaning to watch the video, but it'd be
beneficial to other developers on this list who don't have the time to watch
the whole thing.
ListEntity msgRecpts = dataSvc.prepare(query).asList();
ListKey parents = new ArrayListKey();
for(Entity recep : msgREcpts) {
parents.add(recep.getParent());
}
//Bulk fetch parents using key list
MapKey, Entity msg = dataSvc.get(parents);
//***for second part above, what is the different from doing directly
select in statement in jpa/jdo ?
//***http://gae-java-persistence.blogspot.com/2009/12/queries-with-and-
in-filters.html
One of the benefits of passing a List is type safety. The example in the
link above uses a List of Strings, but you could just as easily define Java
enums with valid values. A more subtle advantage is that were you to use a
StringBuilder with an IN clause, you would be programmatically building a
String, not a List of query parameters. There's no difference at the lower
levels - both techniques get translated to multiple queries, as Max
describes.
--
Ikai Lan
Developer Programs Engineer, Google App Engine
http://googleappengine.blogspot.com | http://twitter.com/app_engine
--
You received this message because you are subscribed to the Google Groups
Google App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] java ip to location library
Is there a library i can use on GAE that will tell me country and probably state based on ip? Thanks -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: One-to-many querying for a child instance
Yes, as you can surmise, I'm guessing.
What's this annotation on the name property for?
@Extension(vendorName=datanucleus, key=gae.pk-name, value=true)
Sydney wrote:
Since I declared the parameter with query.declareParameters(String
nameParam);, the colon is not valid. As expected I got an exception
org.datanucleus.store.query.QueryCompilerSyntaxException: Explicit
parameters defined for query, yet implicit parameter syntax
(:nameParam) found
On Jan 27, 4:39 pm, Rusty Wright rwright.li...@gmail.com wrote:
Do you need a colon in front of nameParam?
query.setFilter(name == :nameParam);
Sydneywrote:
The query returns no result.
ApiProxy.setEnvironmentForCurrentThread(new TestEnvironment
());
ApiProxy.setDelegate(new ApiProxyLocalImpl(new File(.))
{
});
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
PersistenceManagerFactory pmf =
JDOHelper.getPersistenceManagerFactory(transactions-optional);
PersistenceManager pm = pmf.getPersistenceManager();
Transaction tx = pm.currentTransaction();
try {
tx.begin();
pm.makePersistent(a);
tx.commit();
} finally {
if (tx.isActive()) {
tx.rollback();
}
}
System.out.println(a.getKey());
A ap = pm.getObjectById(A.class, A);
System.out.println(ap.getKey());
Query query = pm.newQuery(B.class);
query.setFilter(name == nameParam);
query.declareParameters(String nameParam);
ListB rs = (ListB) query.execute(B);
System.out.println(rs.size());
On Jan 23, 12:20 am, John Patterson jdpatter...@gmail.com wrote:
Execute a query on the name property of B rather than loading it by
key. If the name is unique the result should only contain one B.
On 23 Jan 2010, at 11:41,Sydneywrote:
I have a one to many relationship. There is a problem in the way I
query for a B object. I was wondering what is the best way (most
efficient) to do that.
A a = new A(A);
B b = new B(B);
a.getBs().add(b);
pm.makePersistent(a); // it's done inside a transaction
A ap = pm.getObjectById(A.class, A); // FINE
B bp = pm.getObjectById(B.class, B); // NOT FOUND Exception
I guess B is not found because the real key is not B but B + A key.
How do you get the B object when you don't know nothing about A?
public class A {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
@Extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
@Persistent
@Extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
@Persistent(mappedBy = a)
private ListB bs;
public A(String name) {
this.name = name;
bs = new ArrayListB();
}
... Getter/Setter
}
@PersistenceCapable(identityType =
javax.jdo.annotations.IdentityType.APPLICATION)
public class B {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
@Extension(vendorName = datanucleus, key = gae.encoded-pk,
value = true)
private String key;
@Persistent
@Extension(vendorName = datanucleus, key = gae.pk-name, value
= true)
private String name;
@Persistent
private A a;
public B(String name) {
this.name = name;
}
... Getter/Setter
}
--
You received this message because you are subscribed to the Google
Groups Google App Engine for Java group.
To post to this group, send email to google-appengine-java@googlegroups.com
.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com
.
For more options, visit this group
athttp://groups.google.com/group/google-appengine-java?hl=en
.
--
0x2B | ~0x2b -- Hamlet
--
You received this message because you are subscribed to the Google Groups Google
App Engine for Java group.
To post to this group, send email to google-appengine-j...@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine-java+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: vs-accounting.appspot.com - datastore viewer error
Local file: datastore-indexes !-- Used 2 times in query history -- datastore-index kind=Tenant ancestor=true source=auto property name=tenants_INTEGER_IDX direction=asc/ /datastore-index !-- Used 1 time in query history -- datastore-index kind=Party ancestor=true source=auto property name=partys_INTEGER_IDX direction=asc/ /datastore-index !-- Used 1 time in query history -- datastore-index kind=SecurityGroup ancestor=true source=auto property name=secGrpList_INTEGER_IDX direction=asc/ /datastore-index datastore-index kind=PartyRole ancestor=true source=auto property name=partyRoles_INTEGER_IDX direction=asc/ /datastore-index /datastore-indexes Production: Party partys_INTEGER_IDX ▲ Includes ancestors *Serving* PartyRole partyRoles_INTEGER_IDX ▲ Includes ancestors *Serving* SecurityGroup secGrpList_INTEGER_IDX ▲ Includes ancestors *Serving* Tenant tenants_INTEGER_IDX ▲ Includes ancestors 12hrs ago , the secGrpList_INTEGER_IDX was not shown on the production admin console. Now, it is showing up. The datastore viewer is still responding back error page. -Aswath On Thu, Jan 28, 2010 at 2:48 AM, Ikai L (Google) ika...@google.com wrote: What does you local indexes file look like? Can you post the indexes listed in your production admin console? On Tue, Jan 26, 2010 at 11:24 PM, aswath satrasala aswath.satras...@gmail.com wrote: Hello GAE team, Further observations made while testing the app. I am not able to write entities to the datastore. Upon examining the logs, I found the following error. com.veersoft.action.CreateTenantAction doCreate: com.google.appengine.api.datastore.DatastoreNeedIndexException: no matching index found.. datastore-index kind=SecurityGroup ancestor=true source=manual property name=secGrpList_INTEGER_IDX direction=asc/ /datastore-index The application is fine on the local develpment server. -Aswath On Tue, Jan 26, 2010 at 8:51 PM, aswath satrasala aswath.satras...@gmail.com wrote: Hello, My app-id is vs-accounting. I login into appengine.google.com. I choose the above application. Then I click on the datastore viewer. I get the error Server Error A server error has occurred. Return to Applications screen » https://appengine.google.com/ -Aswath -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Question: best practice to persist medium-large data?
Jeff, I simply reply to your rant about JDO annotations. Nowhere do I say JDO is the solution for all tasks. My goal is not as you state either, but instead to provide persistence via *any* standardised API to all available datastores, and to correct misconceptions about those APIs (whether JDO or JPA), whether caused by misleading GAE/J docs, or by other peoples attitudes. All of the types of things that GAE/J BigTable requires (unindexed etc) are perfectly doable with the available JDO (or to a lesser extent) JPA APIs and metadata (whether annotations or XML) - so the specs are adequate to handle this. How GAE/J have implemented it on top of that only they can comment on, but I'm sure when they have time they'll implement all required patterns. I'll leave you to your goal :-) -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
