BaseContext
Hello, We are using Cayenne 3.0 and recently implemented the WebApplicationContextFilter and we are using BaseContext.getThreadObjectContext(). This is working great for our JSF Web Application. However we introduced Apache Camel into our tech stack. Our Front-End Web Application post a message to a queue that our backend picks up, processes the request and then puts the return results back on a queue which the front end is listening too. When the Front-End receives the information I then want to insert new records into the database. Therefore I try to get a BaseContext.getThreadObjectContext() however it throws a java.lang.IllegalStateException: Current thread has no bound ObjectContext. So it appears the there is no ThreadLocal to attach to and we are likely outside of the WebApplicationContext. Everything works great, when I am within our JSF application flow. I've tried to catch the illegal state error and then return a DataContext.createDataContext(). Unfortunately this did not work either, I get an error saying something like the object is not part of this DataContext. So I already have the parent object from the original request, I then use camel to send a request to the back-end, which returns me data that I need to create the children. I try setting the parent on the child and I get this error. So I'm not sure what to try next. Any suggestions would be greatly appreciated. Thank you, Rich
Re: BaseContext
Try: parentObject = myNewContext.localObject(parentObject); Then proceed with the rest. Then both objects will be in the same ObjectContext. On Thu, Feb 14, 2013 at 9:08 AM, Rich Tuers rtu...@oildex.com wrote: Hello, We are using Cayenne 3.0 and recently implemented the WebApplicationContextFilter and we are using BaseContext.getThreadObjectContext(). This is working great for our JSF Web Application. However we introduced Apache Camel into our tech stack. Our Front-End Web Application post a message to a queue that our backend picks up, processes the request and then puts the return results back on a queue which the front end is listening too. When the Front-End receives the information I then want to insert new records into the database. Therefore I try to get a BaseContext.getThreadObjectContext() however it throws a java.lang.IllegalStateException: Current thread has no bound ObjectContext. So it appears the there is no ThreadLocal to attach to and we are likely outside of the WebApplicationContext. Everything works great, when I am within our JSF application flow. I've tried to catch the illegal state error and then return a DataContext.createDataContext(). Unfortunately this did not work either, I get an error saying something like the object is not part of this DataContext. So I already have the parent object from the original request, I then use camel to send a request to the back-end, which returns me data that I need to create the children. I try setting the parent on the child and I get this error. So I'm not sure what to try next. Any suggestions would be greatly appreciated. Thank you, Rich
Re: BaseContext
Yes, I thought about doing that and this will probably address this one
issue. I guess my real question is how do I keep from
BaseContext.getThreadObjectContext() from throwing that
IllegalStateException. I hit the save button in the UI, create the
Parent objects which does get the ObjectContext back from
BaseContext.getThreadObjectContext(). However before I create the child
objects I put a message on a queue that Camel picks up, processes the
information and then puts the child object data back on the queue. Which
I then pickup and try to create the new children with, using the
BaseContext.getThreadObjectContext(). At this point, it throws the
Illegal state exception. I'm assuming once I go to Camel I lose the
ThreadLocal and therefore get this exception.
Basic Event Flow
---
1. User hits Save
2. Controller calls Front-End service to create Parent Object. Parent
is successfully saved to the database.
3. Front-end service makes a call to the back-end service via Camel (to
get child data).
4. back-end service sends data back to the front-end service.
5. Front-end service tries to create the child objects but gets the
IllegalStateException.
public ObjectContext getDataContext() {
try {
// Successful when creating the parent
return BaseContext.getThreadObjectContext();
} catch (Exception ex) {
// Added this code since I was getting the exception.
// Trying to figure out how to avoid this exception
return DataContext.createDataContext();
}
}
Thanks,
Rich
On 2/14/13 8:24 AM, John Huss johnth...@gmail.com wrote:
Try:
parentObject = myNewContext.localObject(parentObject);
Then proceed with the rest. Then both objects will be in the same
ObjectContext.
On Thu, Feb 14, 2013 at 9:08 AM, Rich Tuers rtu...@oildex.com wrote:
Hello,
We are using Cayenne 3.0 and recently implemented the
WebApplicationContextFilter and we are using
BaseContext.getThreadObjectContext().
This is working great for our JSF Web Application. However we
introduced
Apache Camel into our tech stack. Our Front-End Web Application post a
message to a queue that our backend picks up, processes the request and
then puts the return results back on a queue which the front end is
listening too. When the Front-End receives the information I then want
to insert new records into the database. Therefore I try to get a
BaseContext.getThreadObjectContext() however it throws a
java.lang.IllegalStateException: Current thread has no bound
ObjectContext. So it appears the there is no ThreadLocal to attach to
and we are likely outside of the WebApplicationContext. Everything
works
great, when I am within our JSF application flow.
I've tried to catch the illegal state error and then return a
DataContext.createDataContext(). Unfortunately this did not work
either, I get an error saying something like the object is not part of
this DataContext. So I already have the parent object from the
original
request, I then use camel to send a request to the back-end, which
returns me data that I need to create the children. I try setting the
parent on the child and I get this error.
So I'm not sure what to try next. Any suggestions would be greatly
appreciated.
Thank you,
Rich
Re: BaseContext
You have to bind a context to the thread:
http://cayenne.apache.org/docs/3.0/api/org/apache/cayenne/BaseContext.html#bindThreadObjectContext(org.apache.cayenne.ObjectContext)
Usually this is done by WebApplicationContextFilter. But if you thread
isn't associated with a request or isn't covered by the filter then you
need to create and context and bind it yourself. Also remember to unbind
at some point as well.
On Thu, Feb 14, 2013 at 9:40 AM, Rich Tuers rtu...@oildex.com wrote:
Yes, I thought about doing that and this will probably address this one
issue. I guess my real question is how do I keep from
BaseContext.getThreadObjectContext() from throwing that
IllegalStateException. I hit the save button in the UI, create the
Parent objects which does get the ObjectContext back from
BaseContext.getThreadObjectContext(). However before I create the child
objects I put a message on a queue that Camel picks up, processes the
information and then puts the child object data back on the queue. Which
I then pickup and try to create the new children with, using the
BaseContext.getThreadObjectContext(). At this point, it throws the
Illegal state exception. I'm assuming once I go to Camel I lose the
ThreadLocal and therefore get this exception.
Basic Event Flow
---
1. User hits Save
2. Controller calls Front-End service to create Parent Object. Parent
is successfully saved to the database.
3. Front-end service makes a call to the back-end service via Camel (to
get child data).
4. back-end service sends data back to the front-end service.
5. Front-end service tries to create the child objects but gets the
IllegalStateException.
public ObjectContext getDataContext() {
try {
// Successful when creating the parent
return BaseContext.getThreadObjectContext();
} catch (Exception ex) {
// Added this code since I was getting the exception.
// Trying to figure out how to avoid this exception
return DataContext.createDataContext();
}
}
Thanks,
Rich
On 2/14/13 8:24 AM, John Huss johnth...@gmail.com wrote:
Try:
parentObject = myNewContext.localObject(parentObject);
Then proceed with the rest. Then both objects will be in the same
ObjectContext.
On Thu, Feb 14, 2013 at 9:08 AM, Rich Tuers rtu...@oildex.com wrote:
Hello,
We are using Cayenne 3.0 and recently implemented the
WebApplicationContextFilter and we are using
BaseContext.getThreadObjectContext().
This is working great for our JSF Web Application. However we
introduced
Apache Camel into our tech stack. Our Front-End Web Application post a
message to a queue that our backend picks up, processes the request and
then puts the return results back on a queue which the front end is
listening too. When the Front-End receives the information I then want
to insert new records into the database. Therefore I try to get a
BaseContext.getThreadObjectContext() however it throws a
java.lang.IllegalStateException: Current thread has no bound
ObjectContext. So it appears the there is no ThreadLocal to attach to
and we are likely outside of the WebApplicationContext. Everything
works
great, when I am within our JSF application flow.
I've tried to catch the illegal state error and then return a
DataContext.createDataContext(). Unfortunately this did not work
either, I get an error saying something like the object is not part of
this DataContext. So I already have the parent object from the
original
request, I then use camel to send a request to the back-end, which
returns me data that I need to create the children. I try setting the
parent on the child and I get this error.
So I'm not sure what to try next. Any suggestions would be greatly
appreciated.
Thank you,
Rich
Re: BaseContext
Thank you. Just tried this and it works great. Thanks again.
On 2/14/13 8:47 AM, John Huss johnth...@gmail.com wrote:
You have to bind a context to the thread:
http://cayenne.apache.org/docs/3.0/api/org/apache/cayenne/BaseContext.html
#bindThreadObjectContext(org.apache.cayenne.ObjectContext)
Usually this is done by WebApplicationContextFilter. But if you thread
isn't associated with a request or isn't covered by the filter then you
need to create and context and bind it yourself. Also remember to unbind
at some point as well.
On Thu, Feb 14, 2013 at 9:40 AM, Rich Tuers rtu...@oildex.com wrote:
Yes, I thought about doing that and this will probably address this one
issue. I guess my real question is how do I keep from
BaseContext.getThreadObjectContext() from throwing that
IllegalStateException. I hit the save button in the UI, create the
Parent objects which does get the ObjectContext back from
BaseContext.getThreadObjectContext(). However before I create the
child
objects I put a message on a queue that Camel picks up, processes the
information and then puts the child object data back on the queue.
Which
I then pickup and try to create the new children with, using the
BaseContext.getThreadObjectContext(). At this point, it throws the
Illegal state exception. I'm assuming once I go to Camel I lose the
ThreadLocal and therefore get this exception.
Basic Event Flow
---
1. User hits Save
2. Controller calls Front-End service to create Parent Object. Parent
is successfully saved to the database.
3. Front-end service makes a call to the back-end service via Camel
(to
get child data).
4. back-end service sends data back to the front-end service.
5. Front-end service tries to create the child objects but gets the
IllegalStateException.
public ObjectContext getDataContext() {
try {
// Successful when creating the parent
return BaseContext.getThreadObjectContext();
} catch (Exception ex) {
// Added this code since I was getting the exception.
// Trying to figure out how to avoid this exception
return DataContext.createDataContext();
}
}
Thanks,
Rich
On 2/14/13 8:24 AM, John Huss johnth...@gmail.com wrote:
Try:
parentObject = myNewContext.localObject(parentObject);
Then proceed with the rest. Then both objects will be in the same
ObjectContext.
On Thu, Feb 14, 2013 at 9:08 AM, Rich Tuers rtu...@oildex.com wrote:
Hello,
We are using Cayenne 3.0 and recently implemented the
WebApplicationContextFilter and we are using
BaseContext.getThreadObjectContext().
This is working great for our JSF Web Application. However we
introduced
Apache Camel into our tech stack. Our Front-End Web Application
post a
message to a queue that our backend picks up, processes the request
and
then puts the return results back on a queue which the front end is
listening too. When the Front-End receives the information I then
want
to insert new records into the database. Therefore I try to get a
BaseContext.getThreadObjectContext() however it throws a
java.lang.IllegalStateException: Current thread has no bound
ObjectContext. So it appears the there is no ThreadLocal to
attach to
and we are likely outside of the WebApplicationContext. Everything
works
great, when I am within our JSF application flow.
I've tried to catch the illegal state error and then return a
DataContext.createDataContext(). Unfortunately this did not work
either, I get an error saying something like the object is not
part of
this DataContext. So I already have the parent object from the
original
request, I then use camel to send a request to the back-end, which
returns me data that I need to create the children. I try setting
the
parent on the child and I get this error.
So I'm not sure what to try next. Any suggestions would be greatly
appreciated.
Thank you,
Rich
partially hollow objects
In our Cayenne ROP application we have some tables with very large BLOB fields.
We want to be able to fetch the remaining columns to the client, without the
BLOBs. I am after some ideas on how to best approach this:
1. Create two tables and two Cayenne Java entities to match
Cons: makes the code and database messy since we are dealing with one-to-one
relationships where there isn't really any logical relation
2. Create one database table and use single-table inheritance: the superclass
(say 'Painting') has all the fields and the subclass ('PaintingInfo') only the
lightweight fields
Cons: the code is still messy since casting a PaintingInfo to Painting (should
you want to view the BLOB) isn't really possible. You would have to get the PK
and then perform another full fetch on the parent. And I'd be concerned about
having two objects in memory at the same time which point to the same data, but
aren't synchronised to each other.
3. Devise some mechanism for Cayenne to have not just hollow objects (like what
happens with paged queries) but hollow attributes. Then we only lazily fetch
the attribute data when it is needed (if at all). This could be ROP specific
(that is, the BLOB attributes are fully fetched from the database but not sent
to the client until needed) or perhaps this approach would also be useful in a
non-ROP environment for lazily loading columns.
Any thoughts from people who have run into similar issues? I'd like to avoid
DataRows and all that since that just makes the code really messy again.
Ari
--
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Aristedes Maniatis
ish
http://www.ish.com.au
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