[appengine-java] After upgrade to Java SDK 1.2.5 Key property saved but retrieved as null
Hi,
I am experiencing a problem after upgrading to Java SDK 1.2.5. In a
simple CMS application a page is stored as a CMSPage entity, which
points to its text saved as a DetachedText entity using a Key property
(i.e. an unowned relationship) as follows:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class CMSPage {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
@Persistent
private Key text;
public Key getId() {
return id;
}
public void setId(Key id) {
this.id = id;
}
public Key getText() {
return text;
}
public void setText(Key text) {
this.text = text;
}
}
The Key property text points to:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class DetachedText {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
@Persistent
private Text content;
public DetachedText(Text content) {
this.content = content;
}
public Key getId() {
return id;
}
public Text getContent() {
return content;
}
}
NOTE: I have removed other properties and code that I found unrelated
to the problem
After saving the page I can see the text field populated in the
development console. The value shows as DetachedText(5). I also
verified that the DetachedText entity exists and its ID equals 5.
However, after I retrieve CMSPage from the datastore using a
javax.jdo.Query the text field in the retrieved object is null (both
the Eclipse debugger and the application throwing NPE confirm it).
What am I doing wrong?
Any pointers will be appreciated.
Thanks,
Yegor
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[appengine-java] Re: new stack traces after upgrading to SDK 1.2.5
Vince, If you are interested the reason for the exception is that App Engine does not support threads. Reference finalizer usually runs as a separate thread. In this case the finalizer (correctly) failed to initialize. However, it looks like finalizer is not a critical component in this context. Guice prints a similar stacktrace for its reference finalizer too, also as INFO. Cheers, Yegor On Sep 4, 1:41 pm, Vince Bonfanti vbonfa...@gmail.com wrote: After upgrading to SDK 1.2.5, I've noticed a set of stack traces that show up in both the development environment and on the production server. These only appear if the logging level is set to INFO, and they show up as INFO logs on the production server. I'm pretty sure these are new in SDK 1.2.5 since I've been running at the INFO logging level for quite some time. They only happen for the first request after the application has been restarted. From my production server: com.google.appengine.repackaged.com.google.common.base.FinalizableReference Queue$SystemLoader loadFinalizer: Not allowed to access system class loader. com.google.appengine.repackaged.com.google.common.base.internal.Finalizer getInheritableThreadLocalsField: Couldn't access Thread.inheritableThreadLocals. Reference finalizer threads will inherit thread local values. com.google.appengine.repackaged.com.google.common.base.FinalizableReference Queue init: Failed to start reference finalizer thread. Reference cleanup will only occur when new references are created. java.lang.reflect.InvocationTargetException at com.google.appengine.runtime.Request.process-ad303eae7c610e90(Request.java) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Method.java:40) at com.google.appengine.repackaged.com.google.common.base.FinalizableReference Queue.init(FinalizableReferenceQueue.java:124) at com.google.appengine.repackaged.com.google.common.labs.misc.InterningPools$ 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.cli nit(ProtocolSupport.java:55) at com.google.apphosting.api.DatastorePb$Query.init(DatastorePb.java:1072) at com.google.apphosting.api.DatastorePb$Query$1.init(DatastorePb.java:2355) at com.google.apphosting.api.DatastorePb$Query.clinit(DatastorePb.java:2355) at com.google.appengine.api.datastore.QueryTranslator.convertToPb(QueryTransla tor.java:27) at com.google.appengine.api.datastore.DatastoreServiceImpl$PreparedQueryImpl.c onvertToPb(DatastoreServiceImpl.java:357) at com.google.appengine.api.datastore.DatastoreServiceImpl$PreparedQueryImpl.r unQuery(DatastoreServiceImpl.java:339) at com.google.appengine.api.datastore.DatastoreServiceImpl$PreparedQueryImpl.a ccess$100(DatastoreServiceImpl.java:269) at com.google.appengine.api.datastore.DatastoreServiceImpl$PreparedQueryImpl$1 .iterator(DatastoreServiceImpl.java:303) at org.apache.jsp.test.listEntities_jsp._jspService(listEntities_jsp.java:49) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94) at javax.servlet.http.HttpServlet.service(HttpServlet.java:806) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487) ...truncated --~--~-~--~~~---~--~~ 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 at http://groups.google.com/group/google-appengine-java?hl=en -~--~~~~--~~--~--~---
[appengine-java] Re: After upgrade to Java SDK 1.2.5 Key property saved but retrieved as null
Just so you know, I think I have solved the problem by setting
defaultFetchGroup=true on the Key property:
@Persistent(defaultFetchGroup=true)
private Key text;
Might have something to do with the recently closed issue #58 Queries
don't respect fetch groups:
http://code.google.com/p/datanucleus-appengine/issues/detail?id=58
What's puzzling is that I have unowned relationships all over the
application, however only one class - CMSPage - fails to retrieve the
Key properties.
I am not sure why Key is not automatically in the default fetch group.
Key is not an entity class. It should be ok to fetch it non-lazily by
default.
Yegor
On Sep 4, 1:21 pm, Yegor yegor.jba...@gmail.com wrote:
Hi,
I am experiencing a problem after upgrading to Java SDK 1.2.5. In a
simple CMS application a page is stored as a CMSPage entity, which
points to its text saved as a DetachedText entity using a Key property
(i.e. an unowned relationship) as follows:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class CMSPage {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
@Persistent
private Key text;
public Key getId() {
return id;
}
public void setId(Key id) {
this.id = id;
}
public Key getText() {
return text;
}
public void setText(Key text) {
this.text = text;
}
}
The Key property text points to:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class DetachedText {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
@Persistent
private Text content;
public DetachedText(Text content) {
this.content = content;
}
public Key getId() {
return id;
}
public Text getContent() {
return content;
}
}
NOTE: I have removed other properties and code that I found unrelated
to the problem
After saving the page I can see the text field populated in the
development console. The value shows as DetachedText(5). I also
verified that the DetachedText entity exists and its ID equals 5.
However, after I retrieve CMSPage from the datastore using a
javax.jdo.Query the text field in the retrieved object is null (both
the Eclipse debugger and the application throwing NPE confirm it).
What am I doing wrong?
Any pointers will be appreciated.
Thanks,
Yegor
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[appengine-java] Re: After upgrade to Java SDK 1.2.5 Key property saved but retrieved as null
I think it makes sense now. I did see more exceptions related to
incorrect transaction handling (e.g. updating multiple entities from
different entity groups) that didn't happen prior to 1.2.5. It seems
that it was the upgrade to datanucleus 1.1.5 that triggered these
exceptions. I am not suggesting that 1.1.5 introduced bugs (but
neither denying it). I think it was my code that relied on a previous
bug that got fixed in 1.1.5. Actually I do not require transactions at
this point at all and in the future expect them to be an exception
rather than the norm, so I disabled them and the application is now
running as expected.
Thanks,
Yegor
On Sep 6, 11:08 am, Max Ross maxr+appeng...@google.com wrote:
It shouldn't be inconsistent. The field will only be unavailable outside
the transaction if it was not accessed inside the transaction, so that might
explain why it only happens in certain places.
On Sat, Sep 5, 2009 at 11:55 PM, bgood ben.mcgee.g...@gmail.com wrote:
OK, but why would this behavior be happening inconsistently across his
(and probably others) application?
On Sep 5, 7:06 pm, Max Ross
maxr+appeng...@google.commaxr%2bappeng...@google.com
wrote:
Key is not in the default fetch group because it is an appengine-specific
class. The JDO spec doesn't know anything about app engine so there's no
way that Key could be included in the list of types that are
automatically
included in the default fetch group.
Max
On Fri, Sep 4, 2009 at 1:32 PM, Yegor yegor.jba...@gmail.com wrote:
Just so you know, I think I have solved the problem by setting
defaultFetchGroup=true on the Key property:
@Persistent(defaultFetchGroup=true)
private Key text;
Might have something to do with the recently closed issue #58 Queries
don't respect fetch groups:
http://code.google.com/p/datanucleus-appengine/issues/detail?id=58
What's puzzling is that I have unowned relationships all over the
application, however only one class - CMSPage - fails to retrieve the
Key properties.
I am not sure why Key is not automatically in the default fetch group.
Key is not an entity class. It should be ok to fetch it non-lazily by
default.
Yegor
On Sep 4, 1:21 pm, Yegor yegor.jba...@gmail.com wrote:
Hi,
I am experiencing a problem after upgrading to Java SDK 1.2.5. In a
simple CMS application a page is stored as a CMSPage entity, which
points to its text saved as a DetachedText entity using a Key
property
(i.e. an unowned relationship) as follows:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class CMSPage {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
@Persistent
private Key text;
public Key getId() {
return id;
}
public void setId(Key id) {
this.id = id;
}
public Key getText() {
return text;
}
public void setText(Key text) {
this.text = text;
}
}
The Key property text points to:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class DetachedText {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
@Persistent
private Text content;
public DetachedText(Text content) {
this.content = content;
}
public Key getId() {
return id;
}
public Text getContent() {
return content;
}
}
NOTE: I have removed other properties and code that I found unrelated
to the problem
After saving the page I can see the text field populated in the
development console. The value shows as DetachedText(5). I also
verified that the DetachedText entity exists and its ID equals 5.
However, after I retrieve CMSPage from the datastore using a
javax.jdo.Query the text field in the retrieved object is null
(both
the Eclipse debugger and the application throwing NPE confirm it).
What am I doing wrong?
Any pointers will be appreciated.
Thanks,
Yegor
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[appengine-java] Re: JPA and Scala
Hi, Chris,
Scala is quite interoperable with Java. Wouldn't it make sense to
write data objects in Java and use them from Scala? Or maybe wrap them
into Scala classes to take advantage of Scala facilities? It is, of
course, more work, but it will keep your design clean and should avoid
any Datastore/Datanucleus complications. After all, you data object
definitions are probably a tiny fraction of the rest of the
application.
Yegor
On Oct 13, 11:02 pm, chrislewis burningodzi...@gmail.com wrote:
Hi all,
I've spent hours wrestling with getting some form of a working dev
environment for a Scala (Lift) app on app engine. Getting scala going
is cake, lift not much harder. The pain point is using the datastore.
Given the choice between JDO and JPA, I'm choosing JPA. After spending
hours getting a frankenbuild working, I'm now at issues with the
datastore that have me stumped. Using the following class,
successfully built and enhanced, appengine (under eclipse) throws the
following error when I try to merge() an entity:
javax.jdo.JDOFatalInternalException: It's illegal to call
jdoCopyKeyFieldsToObjectId for a class with SingleFieldIdentity.
The class:
import javax.persistence._
@Entity
class Author {
@Id
@GeneratedValue{ val strategy = GenerationType.IDENTITY }
var id: java.lang.Long = _
var name: String = _
}
Can anyone shed some light on this? Thanks!
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[appengine-java] How to define parent persistent class without identity field
Hi,
Glad to see some reasonable inheritance support in Datastore. However,
I'm a little puzzled. I am trying to setup a simple persistent class
hierarchy, in which the base class defines some standard audit fields
shared by all concrete persistent classes:
public abstract class AbstractEntity implements StoreCallback {
@Persistent
private Date created;
@Persistent
private Date modified;
public final Date getCreated() {
return created;
}
public final Date getModified() {
return modified;
}
@Override
public void jdoPreStore() {
if (this.created == null) {
this.created = new Date();
}
this.modified = new Date();
}
}
The plan was then to have concrete classes extend from this abstract
class and provide the identity field as well as other functional
fields, e.g.:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class Account extends AbstractEntity {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key accountId;
...
}
What JDO annotations would you suggest putting on the AbstractEntity
class to make it work? Everything I tried ends up with either class
not enhanced at runtime or complains about the lack of identity field
on the abstract class. Well, duh! to the latter error message I'd
say.
Any suggestions are welcome.
Thanks,
Yegor
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[appengine-java] Re: How to define parent persistent class without identity field
Thanks for your reply. I guess that's what I will do in my next app. However, in the existing app the identity fields are already defined in the subclasses, and they have different names too, e.g. Account would have accountId, Customer would have customerId, so I cannot move the ID field to the root of the hierarchy as it will not map to the existing data in the App Engine Datastore. This seems very strange. Ability to move common fields into a shared class seems like a very natural thing to do. I am surprised that it is not supported by Datanucleus. That said, I haven't lost all hope. Maybe composition instead of inheritance can help. I am going to check if I can use embedded classes to solve this problem. Yegor On Dec 13, 1:54 am, datanucleus andy_jeffer...@yahoo.com wrote: With all persistence standards, the identity field(s)/property(s) have to be in the base persistent class. -- 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: How to define parent persistent class without identity field
Thanks, Rusty, for your insight. I think this will technically work, but I will have to kiss goodbye to database look-ups by key, which is a big loss. Key look-up is lightning fast compared to querying by index. If I separate accountId from id, then I'll have to GQL something like select from Account where accountId=? as opposed to pm.getObjectById(accountId). I'm still hopeful about the composition approach. I just started coding. Let's see how it goes. Thanks, Yegor On Dec 13, 2:51 pm, Rusty Wright rwright.li...@gmail.com wrote: Another way you could look at is that by using things like customerId and accountId as your database primary keys you're mixing your business stuff with the database persistence stuff. If you create a primary key in the base class and call it something like id, you can still have the accountId and customerId in the subclasses. But ignore that database primary key (id) in your business logic and only use it for database things. You still have and can still use customerId and accountId in queries. Think of the database primary key, id, as just some book keeping stuff, an implementation detail, for the orm (datanucleus).Yegor wrote: Thanks for your reply. I guess that's what I will do in my next app. However, in the existing app the identity fields are already defined in the subclasses, and they have different names too, e.g. Account would have accountId, Customer would have customerId, so I cannot move the ID field to the root of the hierarchy as it will not map to the existing data in the App Engine Datastore. This seems very strange. Ability to move common fields into a shared class seems like a very natural thing to do. I am surprised that it is not supported by Datanucleus. That said, I haven't lost all hope. Maybe composition instead of inheritance can help. I am going to check if I can use embedded classes to solve this problem. Yegor On Dec 13, 1:54 am, datanucleus andy_jeffer...@yahoo.com wrote: With all persistence standards, the identity field(s)/property(s) have to be in the base persistent class. -- 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 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] App Engine down?
My GAE apps (Java) and the app engine dashboard produce intermittent Server 500 errors with a generic message: Error: Server Error The server encountered an error and could not complete your request. If the problem persists, please report your problem and mention this error message and the query that caused it. Because the dashboard is down too I can't even see the error logs. The system status doesn't show any problems except for some Python anomaly. I am on Java. Yegor -- 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: App Engine down?
Yep, it seems to be back to normal. Thanks. On Jul 22, 12:21 pm, Don Schwarz schwa...@google.com wrote: It should be okay now. There was a brief outage that affected some percentage of both Java and Python applications. The Java application that we test to create that dashboard was apparently lucky. On Thu, Jul 22, 2010 at 1:14 PM, Yegor yegor.jba...@gmail.com wrote: My GAE apps (Java) and the app engine dashboard produce intermittent Server 500 errors with a generic message: Error: Server Error The server encountered an error and could not complete your request. If the problem persists, please report your problem and mention this error message and the query that caused it. Because the dashboard is down too I can't even see the error logs. The system status doesn't show any problems except for some Python anomaly. I am on Java. Yegor -- 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%2B unsubscr...@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] Google Plugin for Eclipse 3.6: Unable to connect to repository
Just tried to upgrade to SDK 1.3.7 from Eclipse 3.6, but got this error in a dialog: [QUOTE] Unable to connect to repository http://dl.google.com/eclipse/plugin/3.6/content.xml Unable to connect to repository http://dl.google.com/eclipse/plugin/3.6/content.xml Connection refused: connect [END QUOTE] Following http://dl.google.com/eclipse/plugin/3.6/content.xml in a web browser results in a 404 page not found. I guess I'll have to download the SDK outside of Eclipse. What's up? Thanks, Yegor -- 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: 1.3.8 upgrade delete datastore contents
Actually, I have seen this behaviour in several recent releases of the SDK. At this point, every time I upgrade, I kinda half-expect that my test data will be gone. It would be nice if local data persisted between releases. On Oct 19, 12:20 pm, Ikai Lan (Google) ikai.l+gro...@google.com wrote: This is a known issue with the 1.3.8 release. We're looking into it. -- Ikai Lan Developer Programs Engineer, Google App Engine Blogger:http://googleappengine.blogspot.com Reddit:http://www.reddit.com/r/appengine Twitter:http://twitter.com/app_engine On Mon, Oct 18, 2010 at 11:06 AM, Christian Goudreau goudreau.christ...@gmail.com wrote: Same here and that's kinda problematic, I had a lot of test data and it would take days to reinitialize everything... I guess I'll have no other choice but to come back to AppEngine 1.3.7 since the datastore.bin doesn't seem to be affected. Cheers, On Mon, Oct 18, 2010 at 2:29 AM, Vlad Skarzhevskyy skarzhevs...@gmail.com wrote: My data also disappeared in development environment with the same error. -- 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%2B unsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Christian Goudreau www.arcbees.com -- 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%2B unsubscr...@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: passing multiple parameters to JDOQL
query.declareParameters(Long bind_pocId, Date bind_startDate, Date bind_endDate); This is correct. However, I personally prefer the shorter form, where instead of using filter column == alias along with query.declareParameters(Type alias) you just use filter column == :alias (note the colon before the alias name). Your query can be rewritten as follows: Query query = pm.newQuery(PocVacationSchedule.class); query.setFilter(pocId == :pi startDate == :sd endDate == :ed); ListPocVacationSchedule rulesList = (ListPocVacationSchedule) query.execute(pocId, startFrom, endFrom); -- 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: Concurrency issue when dealing with datastore
I had to strongly synchronize my app using Java options (locka, synchrnized objects, and so on...). I have to warn you that all this synchronization will be in vain once your application grows beyond 1 JVM. Java keyword synchronized is only effective within a single instance of JVM. That is not to say that even with 1 JVM your application may lose a lot of performance if you are synchronizing on static methods or singleton objects, e.g. the datastore. I think it is quite unbelievable that a huge giant like BigTable is so weak in concurrency issues... BigTable gives you a lot of well-documented options to deal with simultaneous access to data. A good place to start is http://code.google.com/appengine/docs/java/datastore/transactions.html. In your case, unless you really have to transact on all entities processed by the servlet, I would recommend that you break your task into several sub-tasks each limited to a single entity group. Perhaps my approach is geared from my experience in relational DBs, but I'm quite puzzeld... Sounds like that might be the case. When working with BigTable, always keep in mind that two entities (called table rows in RDBMS) do not necessarily end up on the same server node. This is good, because it allows BigTable to distribute the load across multiple hard drives. However, when this happens you no longer are able to transact on these entities. Entity groups tell BigTable that two or more related entities must be stored in the database in such a way that a transaction is possible. Unfortunately, you immediately lose scalability within the entity group (thus the recommendation to keep them small). Relational DBs always make that sacrifice by default and put all table rows on the same hard drive. This makes it easy to transact on arbitrary entities. However, you have to partition your database manually to scale. Plus, you cannot transact across partitions, so even with a RDBMS you still have the same limitation. -- 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: Lightweight Best performing MVC framework - Recommendation
http://code.google.com/p/litemvc/ Before you read on, a disclaimer: I am biased as I am one of the commiters to this project - I have used litemvc with a fairly complex appengine application - Really easy to integrate with Guice and Freemarker - Follows Guice configuration philosophy, namely: * No XML * Java-based configuration, e.g.: map(/, IndexHandler.class).templateResult(OK, /index.jsp); - Follows convention-over-configuration for handlers: * Handlers are POJOs * No interfaces and no annotations * Handler method names == HTTP method names, e.g. get(), post() * URL regex groups are mapped to method parameters, e.g. map(/user/ (\\d+), ...) will pass group(1) to get(String userId) * Automatic injection of standard method parameters, such as HttpServetRequest and HttpServletResponse Cheers, Yegor -- 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] Task Queue timing out in 30 sec instead of the promised 10 min on GAE/J SDK 1.4
According to http://code.google.com/appengine/docs/java/taskqueue/overview.html#Task_Execution a single task has up to 10 minutes to execute. However, while testing my app in slow mode I discovered that the GAE/J SDK consistently times out queue tasks in 30 seconds (I'm on version 1.4.0). That is, of course, if the task need more than 30 seconds. Anything below that works fine. Scroll down for a stack trace. Is this a bug in SDK or do I have to configure something in queue.xml to increase the timeout limit? I couldn't find anything in the docs here: http://code.google.com/appengine/docs/java/config/queue.html I do not expect my tasks to exceed 30 seconds, but there might be exceptions, especially because some tasks make heavy use of URLFetch. I decided to check here before submitting a bug report in case I'm being stupid. Thanks, Yegor == [ERROR] Job default.task3 threw an unhandled Exception: com.google.apphosting.api.ApiProxy$ApplicationException: ApplicationError: 5: http method POST against URL http://0.0.0.0:/deferredTaskService timed out. at com.google.appengine.api.urlfetch.dev.LocalURLFetchService.fetch(LocalURLFetchService.java:236) at com.google.appengine.api.taskqueue.dev.LocalTaskQueue$UrlFetchServiceLocalTaskQueueCallback.execute(LocalTaskQueue.java:471) at com.google.appengine.api.taskqueue.dev.UrlFetchJob.execute(UrlFetchJob.java:77) at org.quartz.core.JobRunShell.run(JobRunShell.java:203) at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520) [ERROR] Job (default.task3 threw an exception. org.quartz.SchedulerException: Job threw an unhandled exception. [See nested exception: com.google.apphosting.api.ApiProxy$ApplicationException: ApplicationError: 5: http method POST against URL http://0.0.0.0:/deferredTaskService timed out.] at org.quartz.core.JobRunShell.run(JobRunShell.java:214) at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520) * Nested Exception (Underlying Cause) --- com.google.apphosting.api.ApiProxy$ApplicationException: ApplicationError: 5: http method POST against URL http://0.0.0.0:/deferredTaskService timed out. at com.google.appengine.api.urlfetch.dev.LocalURLFetchService.fetch(LocalURLFetchService.java:236) at com.google.appengine.api.taskqueue.dev.LocalTaskQueue$UrlFetchServiceLocalTaskQueueCallback.execute(LocalTaskQueue.java:471) at com.google.appengine.api.taskqueue.dev.UrlFetchJob.execute(UrlFetchJob.java:77) at org.quartz.core.JobRunShell.run(JobRunShell.java:203) at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520) == -- 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 at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Tiles. Struts. No errors, no exceptions.
Do you mean that all pages work, except one? Or not even one works? I am asking because if it the former, then the problem is page-specific. If it's the latter, then something's wrong with your application config. -- 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 at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Ability to send mail using appspotmail.com
You probably already know this, but just in case you don't, appid has to be replaced with your app's real application id, as defined in your appengine-web.xml (for Java) or app.yaml (for Python). If you knew this already and you still cannot send emails, then you might have found a bug in app-engine. Alternatively, your from address might be blocked by a spam filter. -- 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 at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Cron job limit 30 sec or 10 minutes?
I was wondering about the same question for task queues (http:// groups.google.com/group/google-appengine-java/browse_thread/thread/ 18ee8bfbbfd309fd), but nobody answered. I filed a bug report (http:// code.google.com/p/googleappengine/issues/detail?id=4564) and mentioned cron in it. You might want to star the issue to get more attention from the GAE team. Cheers, Yegor On Feb 11, 4:12 am, pac parvez.chau...@gmail.com wrote: It says here http://code.google.com/appengine/docs/java/config/cron.html A cron job will invoke a URL, using an HTTP GET request, at a given time of day. A URL invoked by cron is subject to the same limits and quotas as a normal HTTP request, including the request time limit. But here it says http://googleappengine.blogspot.com/2010/12/happy-holidays-from-app-e...%20%20It%20says%20here%20%20%20http://code.google.com/appengine/docs/java/config/cron.html%20%20%20% No more 30-second limit for background work - With this release, we’ve significantly raised this limit for offline requests from Task Queue and * Cron*: you can now run for up to 10 minutes without interruption. Clarification/confirmation will be helpful. 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-java@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: raise limits for applications
Hi, Ikai, Interactions between GAE apps and Blobstore are billed for storage + CPU. Google Storage is billed for storage + network + request count. How do the two compare in a real-world scenario from price/performance standpoint? It seems that Blobstore, being a core part of GAE, is regarded as local to your application, while Google Storage will be external and is therefore no different from Amazon S3 or Rackspace CloudFiles. There are also these URL Fetch 1mb-out/32mb-in limits, which seem to apply to everything. It's like we have a Titan 4 class rocket but we're only allowed to use a car engine to fly it. Cheers, Yegor On Mar 23, 6:32 pm, Ikai Lan (Google) ika...@google.com wrote: You should explore: - Blobstore:http://code.google.com/appengine/docs/java/blobstore/overview.html - Google storage:http://code.google.com/apis/storage/ There are other options for application distribution. Ikai Lan Developer Programs Engineer, Google App Engine Blog:http://googleappengine.blogspot.com Twitter:http://twitter.com/app_engine Reddit:http://www.reddit.com/r/appengine On Tue, Mar 22, 2011 at 7:17 AM, Perun Katana gabec@yahoo.com wrote: Hi all, I was thinking if there could be a way to raise the limits for applications. My contecern is, that I have a JNLP application with a nice bunch of libraries included (e.g. jasper reports, etc), which takes the application nicely over 10 MB. The application is built as a Netbeans RPC application, so there is a jnlp-servlet for downloading all necessary files. Unfortunatelly, such applications are rarely under 10 MB. The jnlp-servlet itself does not consume much memory (as far I know), so this is not a problem, To download all libraries may take a little processing time, traffic and request time (well, even for slow trafic I hope each library is downloaded in 30s), but that's why there is billing quota for I am willing to pay. I'd see the google apps as a nice platform to deploy web start applications too, but for bigger application there would be nice to raise request handler quotas too, even if it would be a payed service. I don't think a need a separate VPS instance running 24x7 just to download a jnlp application. The question is, if there is another solution or I'll have to work on getting the static libraries deployed somewhere else (not a bad ide too). Regards Perun -- 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 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-java@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: Blobstore vs. Datastore for HTML files
Brandon, Have you considered storing HTML in compressed form as Datastore blobs? Being plain text HTML should have very high compression ratio. * java.util.zip.GZIPOutputStream is usually no worse than x5, but it is slower * com.ning.compress.lzf.LZFOutputStream should yield x3 compression, but it is faster than GZIP Cheers, Yegor On May 5, 8:14 pm, Brandon Donnelson branflake2...@gmail.com wrote: Entity limit is 1MB total. But you could have multiple blobs within one if they where less than 1MB. Brandon -- 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 at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Cannot upgrade to app engine SDK 1.6.0 on STS 2.8.1
Sounds like you are running an old version of JRE/JDK. On Nov 28, 3:46 pm, AnthoniS anthoni.schioc...@eliium.com wrote: After upgrading STS to 2.8.1 (based on Eclipse 3.7.1) running on MacOSX 10.5.8, i am unable to update the AppEngine SDK to 1.6.0. Here is the error log: java.lang.UnsupportedClassVersionError: Bad version number in .class file at java.lang.ClassLoader.defineClass2(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:775) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java: 160) at java.net.URLClassLoader.defineClass(URLClassLoader.java:254) at java.net.URLClassLoader.access$100(URLClassLoader.java:56) at java.net.URLClassLoader$1.run(URLClassLoader.java:195) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:188) at java.lang.ClassLoader.loadClass(ClassLoader.java:317) at java.lang.ClassLoader.loadClass(ClassLoader.java:252) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:375) at java.lang.Class.getDeclaredConstructors0(Native Method) at java.lang.Class.privateGetDeclaredConstructors(Class.java:2357) at java.lang.Class.getConstructor0(Class.java:2671) at java.lang.Class.newInstance0(Class.java:321) at java.lang.Class.newInstance(Class.java:303) at com.google.appengine.eclipse.core.sdk.AppEngineBridgeFactory.createBridge(A ppEngineBridgeFactory.java: 184) at com.google.appengine.eclipse.core.sdk.AppEngineBridgeFactory.createBridge(A ppEngineBridgeFactory.java: 122) at com.google.appengine.eclipse.core.sdk.AppEngineBridgeFactory.getAppEngineBr idge(AppEngineBridgeFactory.java: 95) at com.google.appengine.eclipse.core.sdk.GaeSdk.getAppEngineBridge(GaeSdk.java : 265) at com.google.appengine.eclipse.core.sdk.GaeSdk.validate(GaeSdk.java: 379) at com.google.gdt.eclipse.core.ui.SdkTable $1.selectionChanged(SdkTable.java:185) at org.eclipse.jface.viewers.Viewer$2.run(Viewer.java:164) at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42) at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49) at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175) at org.eclipse.jface.viewers.Viewer.fireSelectionChanged(Viewer.java: 162) at org.eclipse.jface.viewers.StructuredViewer.updateSelection(StructuredViewer .java: 2188) at org.eclipse.jface.viewers.StructuredViewer.handleSelect(StructuredViewer.ja va: 1211) at org.eclipse.jface.viewers.CheckboxTableViewer.handleSelect(CheckboxTableVie wer.java: 310) at org.eclipse.jface.viewers.StructuredViewer $4.widgetSelected(StructuredViewer.java:1241) at org.eclipse.jface.util.OpenStrategy.fireSelectionEvent(OpenStrategy.java: 239) at org.eclipse.jface.util.OpenStrategy.access$4(OpenStrategy.java: 233) at org.eclipse.jface.util.OpenStrategy $1.handleEvent(OpenStrategy.java:403) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1669) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1693) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1678) at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:1421) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java: 3738) at org.eclipse.swt.widgets.Control.sendTrackEvents(Control.java:3235) at org.eclipse.swt.widgets.Control.kEventControlTrack(Control.java: 2262) at org.eclipse.swt.widgets.Widget.controlProc(Widget.java:381) at org.eclipse.swt.widgets.Display.controlProc(Display.java:916) at org.eclipse.swt.internal.carbon.OS.CallNextEventHandler(Native Method) at org.eclipse.swt.widgets.Table.kEventMouseDown(Table.java:2325) at org.eclipse.swt.widgets.Widget.mouseProc(Widget.java:1387) at org.eclipse.swt.widgets.Display.mouseProc(Display.java:3166) at org.eclipse.swt.internal.carbon.OS.SendEventToEventTarget(Native Method) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3289) at org.eclipse.jface.window.Window.runEventLoop(Window.java:825) at org.eclipse.jface.window.Window.open(Window.java:801) at org.eclipse.ui.internal.dialogs.WorkbenchPreferenceDialog.open(WorkbenchPre ferenceDialog.java: 215) at org.eclipse.ui.internal.handlers.ShowPreferencePageHandler.execute(ShowPref erencePageHandler.java: 54) at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java: 293) at org.eclipse.core.commands.Command.executeWithChecks(Command.java: 476) at
