Nvarchar in Container Managed Bean.

Hi
I m using Oracle 8i with weblogic 6.1. My application has to support NLS. So, I m using NVARCHAR datatype.
When i try to insert into table using CMP, 'Characterset Type Mismatch'! Error is thrown.
Anyone can give how to solve this problem or which datatype to be used to support this.
Thanks in Advance.
Regards
RameshJayaShankar.R
Innova Solution.
[email protected]

Hi Ramesh,
A quick look at my copy of "Oracle 8i: JDBC Developer's Guide and Reference
Release 3 (8.1.7)" tells me -- in table 21-2 on page 21-5 of chapter
21 (Reference Information) -- that the NVARCHAR2 datatype is not supported
by Oracle's JDBC driver or by Oracle's SQLJ. Perhaps that is the reason
for the error message you are receiving?
Hope this helps.
Good Luck,
Avi.

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I am having a problem while trying to create my relations for my container managed bean.
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Container-managed / bean-managed transaction demarcation

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BatchPayment session bean implemented with bean-managed transaction demarcation with transaction scope set to Required.Didn't quite understand this sentence.... if it's BMT it has no declarative transaction attributes such as "Required"....
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If not how is it possible to implement the requirements as described above?You could also implement this scenario with CMTs all the way through. your BatchPayment SB could consist of two methods, one (say, execute(Collection paymentsToExecute) ) with "Supports", and another(say executeBatchUnit(Collection paymentsToExecute, int beginIndex, int endIndex) ) with "RequiresNew".
then have the first just call the other with indexes denoting each time a group of payments.
Still, it does seem more suitable using BMT for these kind of things.....
Hope this helped....

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Re: Exception came when change stateful to stateless in ejb-jar.xml [Ejb 2.0], locking.

BMP (Bean Managed) vs CMP (Contained Managed) Beans

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Actually this is more of a clarification question than an actual issue. To give a background, we're creating a Web Dynpro application that must be connected to an Oracle Database. However,we're in the process of deciding whether to use BMP or CMP to connect the application to the database.
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Thanks!
Angelo

You are probably trapping the exception, so the container never see's it.

How to include Managed bean class in build sciprt for taskflow (Jdev 11.4)

Hi,
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<?xml version="1.0" encoding="US-ASCII" ?>


<project name="WebCenterSpacesSharedLibExtension" default="all" basedir="."
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dir="${jdeveloper.install.home.directory}/oracle_common/common/bin">

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</exec>
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<echo> Restarting the app </echo>
<echo> ---------------------------- </echo>
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Thanks in advance
Nitin

Hi,
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Below is the oracle provide build script..
<?xml version="1.0" encoding="US-ASCII" ?>


<project name="WebCenterSpacesSharedLibExtension" default="all" basedir="."
xmlns:wls="oracle.webcenter.tools.wls">
<property file="../config.properties"/>
<property file="build.properties"/>
<import file="internal-targets.xml"/>
<taskdef resource="net/sf/antcontrib/antcontrib.properties">
<classpath>
<pathelement location="${jdeveloper.install.home.directory}/modules/net.sf.antcontrib_1.0.0.0_1-0b2/lib/ant-contrib.jar"/>
</classpath>
</taskdef>
<target name="clean-stage"
description="Cleans the output directory and generates the war"
depends="clean, stage"/>
<target name="deploy-shared-lib"
depends="init-wls"
description="Deploy the extending WebCenter shared library">
<echo> ---------------------------- </echo>
<echo> ${wls.userconfig} ${wls.userkey} ${wls.host}:${wls.port} ${oracle.jdeveloper.deploy.dir}/exploded ${wls.webcenter.app.target} ${customer.library.name}</echo>
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executable="${jdeveloper.install.home.directory}/oracle_common/common/bin/${wlst.executable}"
dir="${jdeveloper.install.home.directory}/oracle_common/common/bin">

<arg line="${extending.spaces.home.dir}/WebCenterSpacesSharedLibExtension/extspaces.py ${wls.userconfig} ${wls.userkey} ${wls.host}:${wls.port} ${oracle.jdeveloper.deploy.dir}/exploded/${customer.library.name}.war ${wls.webcenter.app.target} ${customer.library.name}"/>


</exec>
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<echo> Restarting the app </echo>
<echo> ---------------------------- </echo>
<exec logerror="true"
executable="${jdeveloper.install.home.directory}/oracle_common/common/bin/${wlst.executable}"
dir="${jdeveloper.install.home.directory}/oracle_common/common/bin">
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Thanks in advance
Nitin

Extreamly slow container managed persistence

Hi.
We perform the following procedure:
1. We invoke a finder method on a container managed bean
2. Then we traverse the enumeration of beans returned and invoke a getter
method to get their properties.
The finder finishes really fast, but then traversing the enumeration takes
about 1 second per entity bean.
Any suggestions?
Giora Katz-Lichtenstein

Hi,
When you're iterating through your collection or enumeration of primary
keys, each method call is going to the database to retrieve the row
associated with that primary key. I'll bet the issue is with the calls to
the db or whatever persistent store you're using.
Steve...
Giora <[email protected]> wrote in message
news:82kolv$192$[email protected]..
Hi.
We perform the following procedure:
1. We invoke a finder method on a container managed bean
2. Then we traverse the enumeration of beans returned and invoke agetter
method to get their properties.
The finder finishes really fast, but then traversing the enumeration takes
about 1 second per entity bean.
Any suggestions?
Giora Katz-Lichtenstein

SetRollbackOnly doesn't work on Container Managed MDB

I have a Container Managed Message Driven Bean + an AQ Queue.
In my onMessage, I call the messageContext.setRollbackOnly() but my message is removed from the queue!
Is it the expected behavior??? It seems that there is a problem with the transactions (for container managed bean)!
I am using oc4j 9.0.3 build 020725.1695 and oracle db 9.0.1.3 with the patch 2416054.
Here is ejb-jar.xml :
<?xml version = '1.0' encoding = 'windows-1252'?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 1.1//EN" "http://java.sun.com/j2ee/dtds/ejb-jar_1_1.dtd">
<ejb-jar>
<enterprise-beans>
<message-driven>
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<ejb-name>test</ejb-name>
<method-name>onMessage</method-name>
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<trans-attribute>RequiresNew</trans-attribute>
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Laurent Lopez

Laurent -- You cannot use "RequiresNew" as the trans-attribute for your MDB. You would use "Required". Here is an excerpt from section 15.4.7 of the EJB 2.0 spec.
The onMessage method is invoked in the scope of a transaction determined by the transaction
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used.[26]
When a message-driven bean using bean-managed transaction demarcation uses the javax.transaction.
UserTransaction interface to demarcate transactions, the message receipt that causes
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used.
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Container Managed Persistence entity bean relationship fields

I want to ask something that until now still confuse. Did Relationship fields in Container Managed Persistence entity beans declare , inside Database table or only Persistence fields .
If Relationship fields not declare inside database table ,how if SQL calls the relationship fields between related entity bean.
did container handle this task.
example: I have 2 entity bean with CMP(Container Managed Persistence)version 2.0
call Player and Team. every entity bean have own relationship fields and persistence fields.
player has playerId(primary key),name,position,age persistence fields and teams is relationship fields.
team has teamId(primary key),name,city and players is relationship fields.
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can you tellme, How SQL calls can access relationship fields if relatiosnship fields is not declare in database table.
I use J2EE RI SDK version 1.3
and deploytool .
thank's .

thank's for your reply .Now I have another problem
I use J2EE RI from java.sun .I try to follow example in j2eetutorial about CMP Example call RosterApp.ear .
I dont'change anything code inside RosterApp.ear but when I deploy and runclient command thereis syntax error :
java.rmi.ServerException: Remote exception occured in server thread :nested exception is java.rmi.ServerException :exception thrown from bean :nested exception is : java.ejb.EJBException :nested exception is :java.sql.SQLException :syntax error or access violation ,message from server: "you have an error in SQL syntax near "
"leagueBeanTable" WHERE "leagueId" = 'L1' at line 1
in example ,RosterApp.ear use Cloudscape database ,but I try to use Mysql database for RosterApp.ear ,is there any different syntax SQL from Cloudscape to Mysql .
if like that ,so I must edit first SQL calls from Cloudscape to MYSQL . I think because relationship fields is for entity beans only ,so how if mysql database want to access foreign key another table because foreign key isn't declare in databse table.
example : I have 3 entity bean call player, team, league .
1. PlayerEJB have persistence fields name, position, playerId(primary key), cmr fields is teams
2. TeamEJB have persistence fields name, city, teamId (primary key) , cmr fields is players and leagues .
3. LeagueEJB have persistence fields name ,sport, leagueId(primary key), cmr fields is teams
so table is
PlayerEJB <--->TeamEJB<--->LeagueEJB
Player have some finder method call findBySport(String Sport) .
because Sport is persistence fields for LeagueEJB
so PlayerEJB must traverse TeamEJB first before LeagueEJB
EJB QL : SELECT distinct object(p) FROM Player (p) IN (p.teams) AS t
WHERE t.league.sport = ?1
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Finder method in container-managed entity bean

Finder method of a container entity bean is taking the primary key class object of another entity bean. How to map this in the xml descriptor file weblogic-cmp-rdbms.xml for this type of beans.
I am trying to deploy the jasmine computer store of Mastering EJB by EdRoman.
I couldn't write the deployment file weblogic-cmp-rdbms.xml for Order Entity bean which uses CustomerPK as an argument in its finder method.
Please tell me how to write this. I am trying on weblogic 5.1
Thanx in advance
Srivatsa

hello,
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Najib.

About Container-managed Transactions and Bean-managed Transactions

as the document of weblogic7.0 describe the differents of Container-managed
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          details of using Bean-managed Transactions,such as \:
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          i wonder someone will show me an example of how to use Container-managed
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          thanks
          fish


Many if not all of the WLS EJB examples use container-managed
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          I'd also recommend that you pick up a decent EJB book. There's several
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          -- Rob
          fish wrote:
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          > <home>test.test.TestHome</home>
          > <remote>test.test.Test</remote>
          > <ejb-class>test.test.TestBean</ejb-class>
          > <session-type>Stateful</session-type>
          > <transaction-type>Container</transaction-type>
          > </session>
          > </enterprise-beans>
          >
          > <assembly-descriptor>
          > <container-transaction>
          > <method>
          > <ejb-name>EmployeeRecord</ejb-name>
          > <method-name>*</method-name>
          > </method>
          > <trans-attribute>Required</trans-attribute>
          > </container-transaction>
          > </assembly-descriptor>
          > </ejb-jar>
          > ----------------------------------------------
          > seems i have to write ejb-jar.xml like this,am i right?
          > what about <ejb-client-jar>? is it needed in this xml file?
          >
          > thanks
          >
          > fish
          >
          >

Bean-Managed vs. Container-Managed Persistence

Hello,
I would like the real world skinny on bean-managed persistence vs. container-managed persistence. I have heard the bean-managed offers higher scalability and performance, while container-managed offers simplicity but with a cost. Can someone give me some perspective?
Thanks,
Rob Miller

Wrong forum, but I guess if you are new to java it could be argued that anything goes...
General rule:
use CMP if you don't have worries about speed or legacy systems.
use BMP if you need to control the persistence and/or want to connect to legacy host systems. BMP allows you to set up caching and transaction handlers to handle the presistence in a manner more suited to your needs.

Bean or Container Managed Persistence

Hi,
I've been reading up on the Sun J2EE tutorial. One of the topics there is bean or container managed persistence. It states that container managed is easier for developers and allows for more portability. The class codes are much smaller compared to bean managed and developers need not worry about database queries.
Can anyone share their experiences on this? Any 'Real World' advantages and disadvantages? Is there a guideline I can follow when to use bean or container managed persistence?
Thanks,
-Ray

That seems like an obvious flaw. So why was it even considered in the
J2EE framework? I mean wouldn't the J2EE architects immediately realize
that? Just doesn't make sense to me why there's even a tutorial or books
for it. What does it suppose to solve then??I know what you mean... again, I think they thought it looked good on paper.
And it gets worse...
Before you use Entity Beans you must be absolutely sure that there will never be another app that accesses the underlying table that doesnt use the EntityBean to do it... For example a C++ App that accesses the tables directly... otherwise you have to set a flag in the App Server that states that basically every time a property on an EntityBean is read the Bean will have to RE-READ the beans state from the database!!
Some things look really good, from an OO perspective, but dont work really well in reality. Sure Entity Beans look really good in the example program in the tutorial, but what happens when you multiply the number of entity beans by 1000, 100,000, or more? Just think of the CPU, and Memory overhead for instantiating all those objects!
There are people out there who believe that using Stored Procedures is a no-no because in their minds it puts "Business Logic" on the database and not the App Server...To this I say... BUNK... Ive seen several instances where by simply moving a set of queries from the App Server to a stored procedure on the database, allowed for a 10-20 times performance gain because of the elimination of network IO. In one instance I saw a query go from 3 hours execution time on the App Server to under 10 minutes on the database... But stored procedures arent OO...
So IMHO before you use EntityBeans at all... be absolutely sure you understand all of the ins-and-outs of doing so.

Nvarchar in Container Managed Bean.

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