Re: Replacing Entities while Managed
The merge operation takes as a parameter a detached instance, not a new instance. TopLink Essentials might not be able to tell the difference between a detached and a new instance. So it might work in that environment. But the behavior you're describing is not portable. That said, you can probably fool OpenJPA into attaching a new instance if you want to. The documentation describes the general heuristics OpenJPA uses to determine whether an instance is detached: http://incubator.apache.org/openjpa/docs/latest/manual/ manual.html#ref_guide_attach_behavior ___ Notice: This email message, together with any attachments, may contain information of BEA Systems, Inc., its subsidiaries and affiliated entities, that may be confidential, proprietary, copyrighted and/or legally privileged, and is intended solely for the use of the individual or entity named in this message. If you are not the intended recipient, and have received this message in error, please immediately return this by email and then delete it.
Re: Replacing Entities while Managed
The merge operation takes as a parameter a detached instance, not a new instance. TopLink Essentials might not be able to tell the difference between a detached and a new instance. So it might work in that environment. But the behavior you're describing is not portable. That said, you can probably fool OpenJPA into attaching a new instance if you want to. The documentation describes the general heuristics OpenJPA uses to determine whether an instance is detached: http://incubator.apache.org/openjpa/docs/latest/manual/ manual.html#ref_guide_attach_behavior ___ Notice: This email message, together with any attachments, may contain information of BEA Systems, Inc., its subsidiaries and affiliated entities, that may be confidential, proprietary, copyrighted and/or legally privileged, and is intended solely for the use of the individual or entity named in this message. If you are not the intended recipient, and have received this message in error, please immediately return this by email and then delete it.
Re: Replacing Entities while Managed
Hi Don, The merge operation takes as a parameter a detached instance, not a new instance. TopLink Essentials might not be able to tell the difference between a detached and a new instance. So it might work in that environment. But the behavior you're describing is not portable. Is there a way to detach an instance with the identity you want to merge, and update that instance? Then you would have a portable application. Craig On Nov 7, 2006, at 4:55 PM, DonBrady wrote: Surely. (1) We do a find method which returns an entity A from the database. (2) We also have an unmanaged entity instance B separately, that we created outside any persistence context, whose values we wish to use to update those in A, and then rewrite A to the database. (3) We just set the key of B to that of A (namely "48") and do a "merge." This worked to update A in TopLink Essentials. (4) Under OpenJPA, we get the exact error message: An object of type "com.xxx.entity.entities.FeCmeCommittee" with oid "48" already exists in this context; another cannot be persisted. (5) This seems wrong. The reason the two objects have the same id is precisely that we want to update the existing entity. THANK YOU. Don Craig L Russell wrote: Hi Don, Could you please be just a bit more specific about what you are trying to do and what error you encounter? Thanks, Craig On Nov 7, 2006, at 2:50 PM, DonBrady wrote: We are converting a TopLink Essentials application to OpenJPA Under Toplink Essentials, we could replace a managed entity with another that had the same identity (key) by doing a merge. When we try this in OpenJPA, we get the following error: An object of type "com.xxx.entity.entities.FeCmeCommittee" with oid "48" already exists in this context; another cannot be persisted. However, "48" is actually the identity or key, not the oid. The oid's are different. They key is the same and therefore it should be possible to replace it via a merge. Or am I missing something? Thanks, Don -- View this message in context: http://www.nabble.com/Replacing- Entities-while-Managed-tf2592059.html#a7229110 Sent from the open-jpa-dev mailing list archive at Nabble.com. Craig Russell Architect, Sun Java Enterprise System http://java.sun.com/products/ jdo 408 276-5638 mailto:[EMAIL PROTECTED] P.S. A good JDO? O, Gasp! -- View this message in context: http://www.nabble.com/Replacing- Entities-while-Managed-tf2592059.html#a7230848 Sent from the open-jpa-dev mailing list archive at Nabble.com. Craig Russell Architect, Sun Java Enterprise System http://java.sun.com/products/jdo 408 276-5638 mailto:[EMAIL PROTECTED] P.S. A good JDO? O, Gasp! smime.p7s Description: S/MIME cryptographic signature
Re: Replacing Entities while Managed
Surely. (1) We do a find method which returns an entity A from the database. (2) We also have an unmanaged entity instance B separately, that we created outside any persistence context, whose values we wish to use to update those in A, and then rewrite A to the database. (3) We just set the key of B to that of A (namely "48") and do a "merge." This worked to update A in TopLink Essentials. (4) Under OpenJPA, we get the exact error message: > An object of type "com.xxx.entity.entities.FeCmeCommittee" with oid > "48" > already exists in this context; another cannot be persisted. > (5) This seems wrong. The reason the two objects have the same id is precisely that we want to update the existing entity. THANK YOU. Don Craig L Russell wrote: > > Hi Don, > > Could you please be just a bit more specific about what you are > trying to do and what error you encounter? > > Thanks, > > Craig > > On Nov 7, 2006, at 2:50 PM, DonBrady wrote: > >> >> We are converting a TopLink Essentials application to OpenJPA >> >> Under Toplink Essentials, we could replace a managed entity with >> another >> that had the same identity (key) by doing a merge. >> >> When we try this in OpenJPA, we get the following error: >> >> An object of type "com.xxx.entity.entities.FeCmeCommittee" with oid >> "48" >> already exists in this context; another cannot be persisted. >> >> However, "48" is actually the identity or key, not the oid. The >> oid's are >> different. They key is the same and therefore it should be >> possible to >> replace it via a merge. >> >> Or am I missing something? >> >> Thanks, >> >> Don >> >> >> -- >> View this message in context: http://www.nabble.com/Replacing- >> Entities-while-Managed-tf2592059.html#a7229110 >> Sent from the open-jpa-dev mailing list archive at Nabble.com. >> > > Craig Russell > Architect, Sun Java Enterprise System http://java.sun.com/products/jdo > 408 276-5638 mailto:[EMAIL PROTECTED] > P.S. A good JDO? O, Gasp! > > > > -- View this message in context: http://www.nabble.com/Replacing-Entities-while-Managed-tf2592059.html#a7230848 Sent from the open-jpa-dev mailing list archive at Nabble.com.
Re: Replacing Entities while Managed
Hi Don, Could you please be just a bit more specific about what you are trying to do and what error you encounter? Thanks, Craig On Nov 7, 2006, at 2:50 PM, DonBrady wrote: We are converting a TopLink Essentials application to OpenJPA Under Toplink Essentials, we could replace a managed entity with another that had the same identity (key) by doing a merge. When we try this in OpenJPA, we get the following error: An object of type "com.xxx.entity.entities.FeCmeCommittee" with oid "48" already exists in this context; another cannot be persisted. However, "48" is actually the identity or key, not the oid. The oid's are different. They key is the same and therefore it should be possible to replace it via a merge. Or am I missing something? Thanks, Don -- View this message in context: http://www.nabble.com/Replacing- Entities-while-Managed-tf2592059.html#a7229110 Sent from the open-jpa-dev mailing list archive at Nabble.com. Craig Russell Architect, Sun Java Enterprise System http://java.sun.com/products/jdo 408 276-5638 mailto:[EMAIL PROTECTED] P.S. A good JDO? O, Gasp! smime.p7s Description: S/MIME cryptographic signature
Replacing Entities while Managed
We are converting a TopLink Essentials application to OpenJPA Under Toplink Essentials, we could replace a managed entity with another that had the same identity (key) by doing a merge. When we try this in OpenJPA, we get the following error: An object of type "com.xxx.entity.entities.FeCmeCommittee" with oid "48" already exists in this context; another cannot be persisted. However, "48" is actually the identity or key, not the oid. The oid's are different. They key is the same and therefore it should be possible to replace it via a merge. Or am I missing something? Thanks, Don -- View this message in context: http://www.nabble.com/Replacing-Entities-while-Managed-tf2592059.html#a7229110 Sent from the open-jpa-dev mailing list archive at Nabble.com.
