Persist object with Hashtable

Hello, I am trying to persist an object with a Hashtable.
I have a Feature object which has a hashtable of qualifiers. Both of the
key and value are of java.lang.String data type.
In my System.jdo:
     <package name="com.primaci.bioprojects.plugins.geneMap">
          <class name="Feature">
               <field name="_qualifiers">
                    <map key-type="java.lang.String" embedded-key="true"
value-type="java.lang.String" embedded-value="true"/>
               </field>
          </class>
     </package>
After running ant, when I try to run the web application, I got the
following exception, is there anything wrong with the system.jdo?
javax.servlet.UnavailableException: Startup exception:
javax.jdo.JDOFatalUserException: The system could not initialize; the
following registered persistent types are missing metadata or have not
been enhanced: [class com.primaci.bioprojects.plugins.geneMap.Feature].
     at
com.primaci.bioprojects.startup.StartupServlet.init(StartupServlet.java:68)
     at javax.servlet.GenericServlet.init(GenericServlet.java:258)
     at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:852)
     at
org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3267)
     at
org.apache.catalina.core.StandardContext.start(StandardContext.java:3384)
     at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1123)
     at org.apache.catalina.core.StandardHost.start(StandardHost.java:612)
     at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1123)
     at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:307)
     at
org.apache.catalina.core.StandardService.start(StandardService.java:388)
     at org.apache.catalina.core.StandardServer.start(StandardServer.java:505)
     at org.apache.catalina.startup.Catalina.start(Catalina.java:776)
     at org.apache.catalina.startup.Catalina.execute(Catalina.java:681)
     at org.apache.catalina.startup.Catalina.process(Catalina.java:179)
     at java.lang.reflect.Method.invoke(Native Method)
     at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:243)

Alex,
What you did looks about right. The exception that you are seeing is
because you have not registered the Feature class with Kodo JDO. You can
do this either by running the schematool or by enumerating all the
persistent types in the 'persistent-types' preference. See the Kodo JDO
User Guide for more information.
-Patrick
[email protected] (Alex Tang) writes:
Hello, I am trying to persist an object with a Hashtable.
I have a Feature object which has a hashtable of qualifiers. Both of the
key and value are of java.lang.String data type.
In my System.jdo:
     <package name="com.primaci.bioprojects.plugins.geneMap">
          <class name="Feature">
               <field name="_qualifiers">
                    <map key-type="java.lang.String" embedded-key="true"
value-type="java.lang.String" embedded-value="true"/>
               </field>
          </class>
     </package>
After running ant, when I try to run the web application, I got the
following exception, is there anything wrong with the system.jdo?
javax.servlet.UnavailableException: Startup exception:
javax.jdo.JDOFatalUserException: The system could not initialize; the
following registered persistent types are missing metadata or have not
been enhanced: [class com.primaci.bioprojects.plugins.geneMap.Feature].
     at
com.primaci.bioprojects.startup.StartupServlet.init(StartupServlet.java:68)
     at javax.servlet.GenericServlet.init(GenericServlet.java:258)
     at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:852)
     at
org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3267)
     at
org.apache.catalina.core.StandardContext.start(StandardContext.java:3384)
     at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1123)
     at org.apache.catalina.core.StandardHost.start(StandardHost.java:612)
     at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1123)
     at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:307)
     at
org.apache.catalina.core.StandardService.start(StandardService.java:388)
     at org.apache.catalina.core.StandardServer.start(StandardServer.java:505)
     at org.apache.catalina.startup.Catalina.start(Catalina.java:776)
     at org.apache.catalina.startup.Catalina.execute(Catalina.java:681)
     at org.apache.catalina.startup.Catalina.process(Catalina.java:179)
     at java.lang.reflect.Method.invoke(Native Method)
     at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:243)
Patrick Linskey [email protected]
SolarMetric Inc. http://www.solarmetric.com

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I have two tables; one is a data table with one key field of type OS_GUID, the second is a mapping table with several business key fields and two further fields; an instance GUID and a class identifier GUID. The data table is used to contain all the data for an object. The mapping table is used to hold a relationship between the GUID assigned in the data table and the business key. The mapping table has been structured in this way by following the help here:
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<-snip->
DATA:
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Create the data...
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<-snip->
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<-snip->
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ENDTRY.
<-snip->
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I'm sorry if the above is hard to follow. Without being able to provide screenshots it's difficult to explain.
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this.relationshipName = relationshipName;
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junit.framework.AssertionFailedError: Unable to create Personal Contact: [Persistent Object [com.riscs.tools.data.udm.support.PersonalContact] save failed.; nested exception is javax.persistence.EntityExistsException:
Exception Description: Cannot persist detached object [com.riscs.tools.data.udm.support.Person@1f47ae8].
Class> com.riscs.tools.data.udm.support.Person Primary Key> [403]]

Hello,
I wasn't clear. Merge is used on unmanaged objects to 'merge' the changes into the managed object. If the object is new, it will return a managed copy of the object. The only difference between merge and persist when passed in a new object, is that persist makes the passed in object managed, where as merge returns a managed copy - the object passed in remains unmanaged.
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Chris

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From help.sap.com:
If several programs use the Persistence Service to instantiate objects of the same class before one of these programs has changed the state using COMMIT WORK, all the objects will have the same initial state. At present, we have not implemented a Persistence Service lock concept, which would ensure that there was only one transient mapping for each persistent object. So ultimately, ABAP programmers are not really working with persistent objects as such; rather, the Persistence Service makes it appear as if they are.
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I've solved the problem like this:
METHOD flush.
"IMPORTING value(im_transient) TYPE REF TO zcl_liquidate_daily_bo
"IMPORTING value(im_commit) TYPE xfeld
"IMPORTING value(im_agent) TYPE REF TO zca_liquidate_daily_bo
"RETURNING value(re_persistent) TYPE REF TO zcl_liquidate_daily_bo
"--> raised by event PERNR_PROCESSED
DATA: s_dip_liq TYPE zhr_tm_dip_liq.
s_dip_liq-zpernr    = im_transient->get_employee_no( ).
s_dip_liq-zsocmat   = im_transient->get_matricola_legale( ).
s_dip_liq-zdataev   = im_transient->get_event_date( ).
s_dip_liq-zcodev    = im_transient->get_event_type( ).
s_dip_liq-zdescev   = im_transient->get_event_descr( ).
s_dip_liq-zmotev    = im_transient->get_event_reasn( ).
s_dip_liq-zmeseall = im_transient->get_mese_allineamento( ).
s_dip_liq-zannoall = im_transient->get_anno_allineamento( ).
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im_agent->if_os_factory~release( im_transient ).
CLEAR im_transient.
IF im_commit EQ abap_true.
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re_persistent =
im_agent->create_persistent( EXPORTING i_anno_allineamento = s_dip_liq-zannoall
                                               i_mese_allineamento = s_dip_liq-zmeseall
                                               i_employee_no       = s_dip_liq-zpernr
                                               i_event_date        = s_dip_liq-zdataev
                                               i_event_type        = s_dip_liq-zcodev
                                               i_event_descr       = s_dip_liq-zdescev
                                               i_event_reasn       = s_dip_liq-zmotev
                                               i_matricola_legale = s_dip_liq-zsocmat ).
      CATCH cx_os_object_existing.
    ENDTRY.
    COMMIT WORK AND WAIT.
ENDIF.
ENDMETHOD.
This method is called inside a loop on a table that containes references to transient objects.
For each object I perform some tasks, and if all it's ok I raise the event PERNR_PROCESSED, which automatically calls this method FLUSH, transferring the transient to the persistent.
Return Object is the new persistent, which will be passed back to the internal table, changing the content from the transient to the new persistent.
Hope this helps,
Roby.

JSF + Hibernate - non- persistant objects in a dataTable

This is more of a conceptual question, concerning creating a dataTable from a list.
I have a User-with-Projects 1:M relationship. Projects are obligatory and not obligatory. I have a user with one compulsory project and a 5 not obligatory. The point is that the 6 projects should be visible in the UI under a h:dataTable component while each inputText from the dataTable should be mapped to beans. The obligatory project is always persisted in the DB, but the others are persisted only if data is inserted in the UI.
So my question is:
How could I form a dataTable, including the 6 project, and check if a data is inserted in the not-compulsory ones?
I tried to create a User object with 6 Project entities (pojo classes), the first one is persisted in the DB and the others are not. This way I had a problem with the lack of ProjectID in the 5 remaining projects (since they are not a part of the DB). The issue could be elsewhere, but that's a rock I hit.
I'll also try creating a ProjectBean with 6 project, on a form submit checking each of the rows for a new data. If user input is available, the project would be inserted in the table. I could also try using an actionListener to check for the input, but I'm not quite sure of getting the correct row I need when the listener is active.
Is there any elegant way of mapping the projects and insert the not- obligatory only if they contain data?
Thanks in advance,
nofearinc

>
Straightforward enough: check if the values aren't null ;) You can also consider to add a valueChangeListener to one or more fields. It would only be fired if the field's value has been changed.
Thanks for the comment, It was just weird for me how to have a User with a List<Project> and not all of the projects are persisted :) It seems a little strange for me as a realization and I assume that Hibernate would also be confused after session saving. That's why I think that I'll need a list of backing beans which would lately be transfered to entities if data is persisted (just being curious if there is more easy and elegant way to do that).
The valueChangeListener would be called after any data is inserted in the row - it's possible that a user could go wrong and edit a field, then erase it again. So I have to insert in the DB only on a form submit (less DB activity).
I'll try this getRowData() method tomorrow, it seems like a reasonable solution if I could use it in my case (dataTable with list of projects and get each row as a particular project).
Thanks again for the reply, I'd be happy to hear any ideas on the subject ;)
nofearinc

Equality between primitive and persistent objects

Folks,
I have discovered by chance that the KODO Query implementation allows me
to test for equality between an Integer and a persistent object. This is
actually phenomenally useful because it allows me to easily work around
some really inefficient auto-generated SQL (see below).
I couldn't find anything about this feature in the JDO specs. Is it
accidental? Is it supported, or likely to disappear in future versions?
Dave Syer.
# 'bean' is an object already loaded from the persistence store
javax.jdo.JDOHelper.getObjectId(bean)Bean-101
# it has one mutable property, which is persistence capable
# and also a read-only property which is the database id
# (Integer) of the property:
javax.jdo.JDOHelper.getObjectId(bean.getProperty())Property-371
bean.getPropertyId()371
# get an extent for querying (pm is the PersistenceManager)
ex=pm.getExtent(Bean,0)# First do a query on property...
qu=pm.newQuery(ex);
qu.declareParameters("Property id1");
qu.setFilter("property == id1")# ...generates SQL with additional unnecessary(?) Cartesian join
# to PROPERTY table:
res=qu.execute(bean.getProperty())# resulting SQL:
# SELECT t0.PROPERTY_ID, t0.PROPERTY_ID FROM BEAN t0, PROPERTY t1
# WHERE (t0.PROPERTY_ID = 371 AND t0.PROPERTY_ID =
# t1.PROPERTY_ID)
# Now do a query on propertyId (Integer)...
qu=pm.newQuery(ex);
qu.declareParameters("java.lang.Integer id1");
qu.setFilter("propertyId == id1")# ...but parameter value is allowed to be a Property -- magically
# turned into an integer when the SQL is generated:
res=qu.execute(bean.getProperty())# resulting SQL:
# SELECT t0.PROPERTY_ID, t0.PROPERTY_ID FROM BEAN t0 WHERE
# t0.PROPERTY_ID = 371

It is accidental and unsupported.Is there any other way to get round the 'unnecessary join' issue that I
mentioned briefly in my original posting? In a real world example, I was
able to improve performance of a single query by a factor of 100 (and my
DB experts tell me there was no way to optimise indexes or anything at the
RDBMS level and achieve the same result).
DAve.

Updation of persistent object

Hi,
I'm using objects persistence. I've created a persistent class and using this for storing data in an index cluster table to use the stored data afterwards.
I've created methods for creating persistent object (using export to database), delete object and read object (using import to database).
But i'm not getting how to use update of existing stored object.
Any help would be appreciated.
Regards
Rajesh

Persistent objects were introduced in ABAP OO in order to replace physical data manipulation via open SQL statements by more abstract OO-typical GET and SET methods for a persistent data object. Has nothing to do with Dequeue/Enqueue.
I recommend reading chapter 3 of [Next Generation ABAP Development|http://www.sappress.com/product.cfm?account=&product=H1986] for the full story.
Greetings
Thomas

Collection of non-persistent objects

Greetings
Is it possible to persist a Collection of non-persistent objects through the
kodo externalization feature? The non-persistent objects themselves are
externalizable, but I don't know how I would go about persisting a
Collection of them.
..droo.

If you store them in some sort of externalized form in a single column it is
easy - just use externalization framework to ext and de-ext them to anf from
string. Couple of caveats you need to be aware of If your collection objects
are mutable:
1. You need to durty your collection field so it get prsisted on commit
2. on rollback Kodo will restore you collection content but not collection
member content. If they are mutable you will have to make their class
persistent with mapping "none" so they participate in transaction
"Drew Lethbridge" <[email protected]> wrote in message
news:BD0B44BF.544%[email protected]..
Greetings
Is it possible to persist a Collection of non-persistent objects throughthe
kodo externalization feature? The non-persistent objects themselves are
externalizable, but I don't know how I would go about persisting a
Collection of them.
.droo.

ObjectId on persistent object

Hello
Using Datastore identity, Is it possible to declare an instance variable on
a persistent object which will "automatically" be populated with the
datastore objectid when the enclosing object is retrieved from persistence?
This would be in preference to always calling JDOHelper.getObjectId(obj)?
[or persistenceManager.getObjectId(obj) ]
Thanks
..droo.

We've done this using the jdoPostLoad callback as follows:
public void jdoPostLoad()
setObjectID(JDOHelper.getObjectId(this).toString());
Scott
Drew Lethbridge wrote:
Hello
Using Datastore identity, Is it possible to declare an instance variable on
a persistent object which will "automatically" be populated with the
datastore objectid when the enclosing object is retrieved from persistence?
This would be in preference to always calling JDOHelper.getObjectId(obj)?
[or persistenceManager.getObjectId(obj) ]
Thanks
..droo.

Need of persistent object

Hi Gurus.,
I am little bit confused over Persistent Objects.. Y we need to use Persistent Objects.. Is it equal to Enquee/Dequee process of normal abap ..
Regards.,
S.Sivakumar

Persistent objects were introduced in ABAP OO in order to replace physical data manipulation via open SQL statements by more abstract OO-typical GET and SET methods for a persistent data object. Has nothing to do with Dequeue/Enqueue.
I recommend reading chapter 3 of [Next Generation ABAP Development|http://www.sappress.com/product.cfm?account=&product=H1986] for the full story.
Greetings
Thomas

Persist object with Hashtable

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