Design pattern suggestion for multiple PersistenceManagers?

Hi!
I'm getting the following error (see end of message), and I would love to
hear a good design solution.
I get this error when adding a RequestLog object into the db, which
contains a field for User. Now, I pass in the User object and since I am
use a ThreadLocal pool for PersistenceManagers, sometimes the User object
is being monitored by another PersistenceManager.
Firstly, why is that causing a problem? I am not updating or changing the
User object from this RequestLog object?
I attempted to make the User object non-transactional, and I have
javax.jdo.option.NontransactionalRead: true
javax.jdo.option.NontransactionalWrite: true
in my kodo.properties, but that made no improvement.
What is the standard solution to this type of problem?
Thanks!
Nic.
Stack trace:
com.solarmetric.kodo.runtime.UserException: The instance
"com.everwhere.idiomatica.app.security.User" of id
"com.everwhere.idiomatica.app.security.User-0" is not managed by this
PersistenceManager.
FailedObject:User: admin
     at
com.solarmetric.kodo.runtime.PersistenceManagerImpl.makePersistentFilter(PersistenceManagerImpl.java:1402)
     at
com.solarmetric.kodo.runtime.PersistFCOFieldManager.storeFirstClassObject(PersistFCOFieldManager.java:109)
     at
com.solarmetric.kodo.runtime.PersistFCOFieldManager.storeObjectField(PersistFCOFieldManager.java:78)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.providedObjectField(StateManagerImpl.java:1354)
     at
com.everwhere.idiomatica.app.etc.request.TranslationRequest.jdoProvideField(TranslationRequest.java)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.provideFields(StateManagerImpl.java:2360)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.preFlush(StateManagerImpl.java:2037)
     at com.solarmetric.kodo.runtime.PNewState.beforeCommit(PNewState.java:39)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.beforeCommit(StateManagerImpl.java:597)
     at
com.solarmetric.kodo.runtime.PersistenceManagerImpl.preCommitCallbacks(PersistenceManagerImpl.java:650)
     at
com.solarmetric.kodo.runtime.PersistenceManagerImpl.commit(PersistenceManagerImpl.java:454)
     at
com.everwhere.idiomatica.db.KodoDatabase.insertDirectlyIntoDB(KodoDatabase.java:45)

You cannot share objects directly across multiple pms.
For example:
Person p = (Person) pm1.getObjectById ...
Person p2 = (Person) pm2.getObjectById ...
p.setParent (p2); // bad!
instead you should do:
p2.setParent ((Person) pm2.getObjectById (JDOHelper.getObjectId (p),
false));
This should be a low cost operation (and even more so with L2 caching)
It is usually best to allocate a PM per context so that these
semi-messy situations are avoided.
On Wed, 18 Jun 2003 10:53:09 +0000, Nic Cottrell wrote:
Hi!
I'm getting the following error (see end of message), and I would love to
hear a good design solution.
I get this error when adding a RequestLog object into the db, which
contains a field for User. Now, I pass in the User object and since I am
use a ThreadLocal pool for PersistenceManagers, sometimes the User object
is being monitored by another PersistenceManager.
Firstly, why is that causing a problem? I am not updating or changing the
User object from this RequestLog object?
I attempted to make the User object non-transactional, and I have
javax.jdo.option.NontransactionalRead: true
javax.jdo.option.NontransactionalWrite: true
in my kodo.properties, but that made no improvement.
What is the standard solution to this type of problem?
Thanks!
Nic.
Stack trace:
com.solarmetric.kodo.runtime.UserException: The instance
"com.everwhere.idiomatica.app.security.User" of id
"com.everwhere.idiomatica.app.security.User-0" is not managed by this
PersistenceManager.
FailedObject:User: admin
     at
com.solarmetric.kodo.runtime.PersistenceManagerImpl.makePersistentFilter(PersistenceManagerImpl.java:1402)
     at
com.solarmetric.kodo.runtime.PersistFCOFieldManager.storeFirstClassObject(PersistFCOFieldManager.java:109)
     at
com.solarmetric.kodo.runtime.PersistFCOFieldManager.storeObjectField(PersistFCOFieldManager.java:78)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.providedObjectField(StateManagerImpl.java:1354)
     at
com.everwhere.idiomatica.app.etc.request.TranslationRequest.jdoProvideField(TranslationRequest.java)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.provideFields(StateManagerImpl.java:2360)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.preFlush(StateManagerImpl.java:2037)
     at com.solarmetric.kodo.runtime.PNewState.beforeCommit(PNewState.java:39)
     at
com.solarmetric.kodo.runtime.StateManagerImpl.beforeCommit(StateManagerImpl.java:597)
     at
com.solarmetric.kodo.runtime.PersistenceManagerImpl.preCommitCallbacks(PersistenceManagerImpl.java:650)
     at
com.solarmetric.kodo.runtime.PersistenceManagerImpl.commit(PersistenceManagerImpl.java:454)
     at
com.everwhere.idiomatica.db.KodoDatabase.insertDirectlyIntoDB(KodoDatabase.java:45)--
Steve Kim
[email protected]
SolarMetric Inc.
http://www.solarmetric.com

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"You live in a graphical world. Why not program in one?"
Solved!
Go to Solution.

johnsold wrote:
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senthil

Of course that program is not an object design pattern
(Its just a little ABAP Objects syntax demo that I wrote years ago
I don't know about a list of OO design patterns implemented in ABAP Objects.
A very simple one, a Singleton might look like this:
<b>* cl_singleton: Eager Variant
CLASS cl_singleton DEFINITION FINAL
                              CREATE PRIVATE.
PUBLIC SECTION.
    CLASS-METHODS: class_constructor,
                   get_singleton RETURNING VALUE(singleton)
                                           TYPE REF TO cl_singleton.
PRIVATE SECTION.
    CLASS-DATA singleton TYPE REF TO cl_singleton.
ENDCLASS.
CLASS cl_singleton IMPLEMENTATION.
METHOD class_constructor.
    CREATE OBJECT singleton.
ENDMETHOD.
METHOD get_singleton.
    singleton = cl_singleton=>singleton.
ENDMETHOD.
ENDCLASS.
cl_singleton: Lazy Variant
CLASS cl_singleton DEFINITION FINAL
                              CREATE PRIVATE.
PUBLIC SECTION.
    CLASS-METHODS get_singleton RETURNING VALUE(singleton)
                                          TYPE REF TO cl_singleton.
PRIVATE SECTION.
    CLASS-DATA singleton TYPE REF TO cl_singleton.
ENDCLASS.
CLASS cl_singleton IMPLEMENTATION.
METHOD get_singleton.
    IF cl_singleton=>singleton IS INITIAL.
      CREATE OBJECT cl_singleton=>singleton.
    ENDIF.
    singleton = cl_singleton=>singleton.
ENDMETHOD.
ENDCLASS.</b>

For multiple item selection in Table

Plz use this code and paste it in perticular event of button. when u excute the application ,To select multiple items plz catch shift in keyboard otherwise u can select only single item.
int n = wdContext.nodeProducts().size();
    int leadSelected = wdContext.nodeProducts().getLeadSelection();
    // loop backwards to avoid index troubles
    for (int i = n - 1; i >= 0; --i) {
      if (wdContext.nodeProducts().isMultiSelected(i) || leadSelected == i) {
        wdContext.nodeProducts().removeElement(wdContext.nodeProducts().getElementAt(i));

Hi Vishal
Thats the way the webdynpro table has been designed to work for multiple selection...on click of the Ctrl key or Shift key. There is no other alternative for this.
What would your question be?
Thanks
oj

Suggest good book for J2EE Design Pattern.

Is there any good book for J2EE Design pattern? I know Head First Design Pattern book, but is focuses oncore java. I want to learn in detail with examples J2EE design pattern.
Please suggest good books.
Thanks in advance.
Rahul.

most j2ee patterns are discredited now. they were mostly workarounds for deficiencies in ejb 1 & 2 specs.
"core j2ee patterns" is your best bet, but take it with a grain of salt.
better to learn spring, IMO:
springframework.org
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Design pattern suggestion for multiple PersistenceManagers?

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