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Posted to users@openjpa.apache.org by Akash Gunjal <ak...@in.ibm.com> on 2013/10/17 17:54:14 UTC
Fetching data from entity manager
Hello,
The problem scenario is as described below.
OpenJpa is used to manage entities in websphere liberty. There are two
entities managed by different entity managers. When the first entity is in
transaction, it tries to access a property from the second entity by
invoking a select query. The second entity manager is invoked through a
service injected using blueprint at the server start-up. But when the
second entity is being fetched, the application hangs and never comes back.
There is no exception thrown but the application never recovers from the
hang state.
Regards,
Akash
Re: JPA exception while persistence into database
Posted by Rick Curtis <cu...@gmail.com>.
Is there any reason that you need to use two different persistence units?
Why not merge them into one? I'm going to suggest that you find a copy of
Pro JPA 2 and take a read through that. It will help give you a better
understanding of how to properly use JPA.
Also, be aware that openjpa.Multithreaded has a number of known bugs.
Ideally you should avoid sharing EntityManagers across threads rather than
using that property.
Thanks,
Rick
On Mon, Oct 21, 2013 at 9:15 PM, Akash Gunjal <ak...@in.ibm.com> wrote:
> Hi,
>
> Both entities belong to different persistence units and have their own
> entity managers. I have pasted the persistence.xml snippet below for both
> the persistence files. The Zone entity in persistenceUnit1 has a field
> property of Policy entity also in persistenceUnit1. This Policy entity is a
> base class of another entity CustomPolicy which is in persistenceUnit2. I
> am trying to persist the Zone with entity manager of persistenceUnit1. This
> is when I hit the problem. If we cannot persist this way, then what could
> be solution to this issue.
>
> <persistence-unit name="PersistenceUnit1">
> <jta-data-source>jdbc/db2connection</jta-data-source>
> <class>mypack.src.Policy</class>
> <class>mypack.src.Zone</class>
> <exclude-unlisted-classes>false</exclude-unlisted-classes>
> <validation-mode>NONE</validation-mode>
> <properties>
> <!-- Create the database tables on startup -->
> <property name="openjpa.jdbc.SynchronizeMappings"
> value=
> "buildSchema(ForeignKeys=true)"/>
> <property name="openjpa.Log"
> value="DefaultLevel=ERROR"/>
> <property name="openjpa.jdbc.DBDictionary"
> value="db2"/>
> <property name="openjpa.Multithreaded"
> value="true"/>
> <property name="openjpa.jdbc.TransactionIsolation"
> value="read-committed" />
> </properties>
> </persistence-unit>
>
>
>
> <persistence-unit name="PersistenceUnit2">
> <jta-data-source>jdbc/db2connection</jta-data-source>
> <class>mycustom.src.CustomPolicy</class>
> <class>mypack.src.Policy</class>
> <exclude-unlisted-classes>true</exclude-unlisted-classes>
> <validation-mode>NONE</validation-mode>
> <properties>
> <!-- Create the database tables on startup -->
> <property name="openjpa.jdbc.SynchronizeMappings"
> value=
> "buildSchema(ForeignKeys=true)"/>
> <property name="openjpa.Log"
> value="DefaultLevel=ERROR"/>
> <property name="openjpa.jdbc.DBDictionary"
> value="db2"/>
> <property name="openjpa.Multithreaded"
> value="true"/>
> <property name="openjpa.jdbc.TransactionIsolation"
> value="read-committed" />
> </properties>
> </persistence-unit>
>
>
> Regards,
> Akash
>
>
>
> From: Rick Curtis <cu...@gmail.com>
> To: users <us...@openjpa.apache.org>,
> Date: 10/22/2013 12:42 AM
> Subject: Re: JPA exception while persistence into database
>
>
>
> > That entity has a field associated with another entity. Both these
> entities belong to different persistence units.
> You can't persist a relationship from an Entity to another Entity that
> belongs in a different persistence units. An EntityManager will only
> operate against Entities that are a part of it's persistence unit
> definition. Do you truly have two different persistence units, or do you
> just have two different EntityManagers?
>
>
>
> On Mon, Oct 21, 2013 at 11:50 AM, Akash Gunjal <ak...@in.ibm.com>
> wrote:
>
> > Hi,
> >
> > I am trying to persist an entity into the database. That entity has a
> field
> > associated with another entity. Both these entities belong to different
> > persistence units. When trying to persist the entity I get the below
> error.
> >
> > > Invalid parameter - Encountered unmanaged object
> > "com.ibm.powersc.ts.policies.vlan.persistence.VLANPolicy@40004000" in
> life
> > cycle state unmanaged while cascading persistence via field
> > "com.ibm.sc.core.persistence.Zone.policies<element:class
> > com.ibm.sc.core.persistence.Policy>" during flush. However, this field
> > does not allow cascade persist. You cannot flush unmanaged objects or
> > graphs that have persistent associations to unmanaged objects.
> > Suggested actions: a) Set the cascade attribute for this field to
> > CascadeType.PERSIST or CascadeType.ALL (JPA annotations) or "persist" or
> > "all" (JPA orm.xml),
> > b) enable cascade-persist globally,
> > c) manually persist the related field value prior to flushing.
> > d) if the reference belongs to another context, allow reference to it by
> > setting StoreContext.setAllowReferenceToSiblingContext().
> >
> >
> > I tried to give cascade.All option to the field having entity reference,
> > then I get an error message "This entity is not managed by this context".
> >
> > Regards,
> > Akash
> >
> >
>
>
> --
> *Rick Curtis*
>
>
>
--
*Rick Curtis*
Re: JPA exception while persistence into database
Posted by Akash Gunjal <ak...@in.ibm.com>.
Hi,
Both entities belong to different persistence units and have their own
entity managers. I have pasted the persistence.xml snippet below for both
the persistence files. The Zone entity in persistenceUnit1 has a field
property of Policy entity also in persistenceUnit1. This Policy entity is a
base class of another entity CustomPolicy which is in persistenceUnit2. I
am trying to persist the Zone with entity manager of persistenceUnit1. This
is when I hit the problem. If we cannot persist this way, then what could
be solution to this issue.
<persistence-unit name="PersistenceUnit1">
<jta-data-source>jdbc/db2connection</jta-data-source>
<class>mypack.src.Policy</class>
<class>mypack.src.Zone</class>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<validation-mode>NONE</validation-mode>
<properties>
<!-- Create the database tables on startup -->
<property name="openjpa.jdbc.SynchronizeMappings" value=
"buildSchema(ForeignKeys=true)"/>
<property name="openjpa.Log" value="DefaultLevel=ERROR"/>
<property name="openjpa.jdbc.DBDictionary" value="db2"/>
<property name="openjpa.Multithreaded" value="true"/>
<property name="openjpa.jdbc.TransactionIsolation"
value="read-committed" />
</properties>
</persistence-unit>
<persistence-unit name="PersistenceUnit2">
<jta-data-source>jdbc/db2connection</jta-data-source>
<class>mycustom.src.CustomPolicy</class>
<class>mypack.src.Policy</class>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<validation-mode>NONE</validation-mode>
<properties>
<!-- Create the database tables on startup -->
<property name="openjpa.jdbc.SynchronizeMappings" value=
"buildSchema(ForeignKeys=true)"/>
<property name="openjpa.Log" value="DefaultLevel=ERROR"/>
<property name="openjpa.jdbc.DBDictionary" value="db2"/>
<property name="openjpa.Multithreaded" value="true"/>
<property name="openjpa.jdbc.TransactionIsolation"
value="read-committed" />
</properties>
</persistence-unit>
Regards,
Akash
From: Rick Curtis <cu...@gmail.com>
To: users <us...@openjpa.apache.org>,
Date: 10/22/2013 12:42 AM
Subject: Re: JPA exception while persistence into database
> That entity has a field associated with another entity. Both these
entities belong to different persistence units.
You can't persist a relationship from an Entity to another Entity that
belongs in a different persistence units. An EntityManager will only
operate against Entities that are a part of it's persistence unit
definition. Do you truly have two different persistence units, or do you
just have two different EntityManagers?
On Mon, Oct 21, 2013 at 11:50 AM, Akash Gunjal <ak...@in.ibm.com> wrote:
> Hi,
>
> I am trying to persist an entity into the database. That entity has a
field
> associated with another entity. Both these entities belong to different
> persistence units. When trying to persist the entity I get the below
error.
>
> > Invalid parameter - Encountered unmanaged object
> "com.ibm.powersc.ts.policies.vlan.persistence.VLANPolicy@40004000" in
life
> cycle state unmanaged while cascading persistence via field
> "com.ibm.sc.core.persistence.Zone.policies<element:class
> com.ibm.sc.core.persistence.Policy>" during flush. However, this field
> does not allow cascade persist. You cannot flush unmanaged objects or
> graphs that have persistent associations to unmanaged objects.
> Suggested actions: a) Set the cascade attribute for this field to
> CascadeType.PERSIST or CascadeType.ALL (JPA annotations) or "persist" or
> "all" (JPA orm.xml),
> b) enable cascade-persist globally,
> c) manually persist the related field value prior to flushing.
> d) if the reference belongs to another context, allow reference to it by
> setting StoreContext.setAllowReferenceToSiblingContext().
>
>
> I tried to give cascade.All option to the field having entity reference,
> then I get an error message "This entity is not managed by this context".
>
> Regards,
> Akash
>
>
--
*Rick Curtis*
Re: JPA exception while persistence into database
Posted by Rick Curtis <cu...@gmail.com>.
> That entity has a field associated with another entity. Both these
entities belong to different persistence units.
You can't persist a relationship from an Entity to another Entity that
belongs in a different persistence units. An EntityManager will only
operate against Entities that are a part of it's persistence unit
definition. Do you truly have two different persistence units, or do you
just have two different EntityManagers?
On Mon, Oct 21, 2013 at 11:50 AM, Akash Gunjal <ak...@in.ibm.com> wrote:
> Hi,
>
> I am trying to persist an entity into the database. That entity has a field
> associated with another entity. Both these entities belong to different
> persistence units. When trying to persist the entity I get the below error.
>
> > Invalid parameter - Encountered unmanaged object
> "com.ibm.powersc.ts.policies.vlan.persistence.VLANPolicy@40004000" in life
> cycle state unmanaged while cascading persistence via field
> "com.ibm.sc.core.persistence.Zone.policies<element:class
> com.ibm.sc.core.persistence.Policy>" during flush. However, this field
> does not allow cascade persist. You cannot flush unmanaged objects or
> graphs that have persistent associations to unmanaged objects.
> Suggested actions: a) Set the cascade attribute for this field to
> CascadeType.PERSIST or CascadeType.ALL (JPA annotations) or "persist" or
> "all" (JPA orm.xml),
> b) enable cascade-persist globally,
> c) manually persist the related field value prior to flushing.
> d) if the reference belongs to another context, allow reference to it by
> setting StoreContext.setAllowReferenceToSiblingContext().
>
>
> I tried to give cascade.All option to the field having entity reference,
> then I get an error message "This entity is not managed by this context".
>
> Regards,
> Akash
>
>
--
*Rick Curtis*
JPA exception while persistence into database
Posted by Akash Gunjal <ak...@in.ibm.com>.
Hi,
I am trying to persist an entity into the database. That entity has a field
associated with another entity. Both these entities belong to different
persistence units. When trying to persist the entity I get the below error.
> Invalid parameter - Encountered unmanaged object
"com.ibm.powersc.ts.policies.vlan.persistence.VLANPolicy@40004000" in life
cycle state unmanaged while cascading persistence via field
"com.ibm.sc.core.persistence.Zone.policies<element:class
com.ibm.sc.core.persistence.Policy>" during flush. However, this field
does not allow cascade persist. You cannot flush unmanaged objects or
graphs that have persistent associations to unmanaged objects.
Suggested actions: a) Set the cascade attribute for this field to
CascadeType.PERSIST or CascadeType.ALL (JPA annotations) or "persist" or
"all" (JPA orm.xml),
b) enable cascade-persist globally,
c) manually persist the related field value prior to flushing.
d) if the reference belongs to another context, allow reference to it by
setting StoreContext.setAllowReferenceToSiblingContext().
I tried to give cascade.All option to the field having entity reference,
then I get an error message "This entity is not managed by this context".
Regards,
Akash
Re: Fetching data from entity manager
Posted by Rick Curtis <cu...@gmail.com>.
Have you take a thread dump to see what the 'hung' thread is doing? Is it
possible that the 'hung' thread is actually loading much more data than you
are expecting, and as such, taking a long time to execute?
Thanks,
Rick
On Thu, Oct 17, 2013 at 10:54 AM, Akash Gunjal <ak...@in.ibm.com> wrote:
>
> Hello,
>
> The problem scenario is as described below.
>
> OpenJpa is used to manage entities in websphere liberty. There are two
> entities managed by different entity managers. When the first entity is in
> transaction, it tries to access a property from the second entity by
> invoking a select query. The second entity manager is invoked through a
> service injected using blueprint at the server start-up. But when the
> second entity is being fetched, the application hangs and never comes back.
> There is no exception thrown but the application never recovers from the
> hang state.
>
> Regards,
> Akash
>
>
--
*Rick Curtis*