Bean managed persistence

[bernd_roedel]

Hello,

I am looking for examples where JCO is used to implement

bean managed persistence of entity beans.

Has anybody tried this before?

Best regards

Bernd Rödel

[Former Member · Accepted solution]

Hi,

why do you want to use a Entity Bean ? Just to get the advantages of ejbLoad() / ejbStore() syncronization ?

I have implemented it with Stateful Session Bean which is no big deal. I will send you the code if u like.

Regards

Matthias

[bernd_roedel · Accepted solution]

Hello,

the idea is exactly to use BMP as back-end synchronisation. However I thought also about leaving out the persistence layer and accessing directly from session beans. If I change my mind, I would like to come back to your offer. Thanks so far.

Best regards

Bernd

[bernd_roedel]

Problem has been solved. JCO and BMP can be combined.

[Former Member]

Hi,

to my opinion you might (!!) end up in trouble using BMPoverJCO but it might be worth a try.

Within ejbCreate you have to return the primary key to let the container know how to get the object/data further on. This is stored within the EJBContext (and could/should be get from there).

Take care for the ejbPostCreate as the PK is assigned AFTER ejbCreate.

Any synchronizing by ejbLoad/ejbStore - which is invoked by the container solely - uses this PK.

So override these methods and look what happens.

As you could not make use of a DataSource, I would encapsulate the connection to SAP elsewhere but not within the BMP EJB (you might end up in hundreds of connections to SAP, depending on EJB instances. JCO offers a Pool which is easy to implement. I could provide you with more details on this.

BTW, let me know if you succeeded

Regards

M.

[bernd_roedel]

Hi,

thanks for the input. I already use connection pooling with JCO. I let you know if it works with BMP.

Best regards

Bernd

[bernd_roedel]

Hi,

I tried with BMP, but I get an deployment error. Do you have any clues ?

Thanks in advance

Bernd

5#000E9BAED2030054000000120000087800040C26CB122447#1139260662001#com.sap.engine.services.deploy##com.sap.engine.services.deploy#Administrator#614#####SAPEngine_Application_Thread[impl:3]_35##0#0#Error#1#/System/Server#Java#deploy_5029##Exception in operation deploy with application sap.com/PersistenceEAR.#2#deploy#sap.com/PersistenceEAR#

#1.5#000E9BAED2030054000000130000087800040C26CB122E87#1139260662001#com.sap.engine.services.deploy##com.sap.engine.services.deploy#Administrator#614#####SAPEngine_Application_Thread[impl:3]_35##0#0#Error#1#/System/Audit#Java###Exception #1#com.sap.engine.services.deploy.exceptions.ServerDeploymentException: Exception in operation deploy with application sap.com/PersistenceEAR.

at com.sap.engine.services.deploy.server.application.ApplicationTransaction.rollbackPart(ApplicationTransaction.java:387)

at com.sap.engine.services.deploy.server.application.ApplicationTransaction.makeAllPhasesOnOneServer(ApplicationTransaction.java:292)

at com.sap.engine.services.deploy.server.application.ApplicationTransaction.makeAllPhases(ApplicationTransaction.java:323)

at com.sap.engine.services.deploy.server.DeployServiceImpl.makeGlobalTransaction(DeployServiceImpl.java:3027)

at com.sap.engine.services.deploy.server.DeployServiceImpl.deploy(DeployServiceImpl.java:467)

at com.sap.engine.services.deploy.server.DeployServiceImplp4_Skel.dispatch(DeployServiceImplp4_Skel.java:1555)

at com.sap.engine.services.rmi_p4.DispatchImpl._runInternal(DispatchImpl.java:294)

at com.sap.engine.services.rmi_p4.DispatchImpl._run(DispatchImpl.java:183)

at com.sap.engine.services.rmi_p4.server.P4SessionProcessor.request(P4SessionProcessor.java:119)

at com.sap.engine.core.service630.context.cluster.session.ApplicationSessionMessageListener.process(ApplicationSessionMessageListener.java:33)

at com.sap.engine.core.cluster.impl6.session.MessageRunner.run(MessageRunner.java:41)

at com.sap.engine.core.thread.impl3.ActionObject.run(ActionObject.java:37)

at java.security.AccessController.doPrivileged(Native Method)

at com.sap.engine.core.thread.impl3.SingleThread.execute(SingleThread.java:95)

at com.sap.engine.core.thread.impl3.SingleThread.run(SingleThread.java:160)

Caused by: com.sap.engine.services.deploy.exceptions.ServerDeploymentException: Cannot deploy application sap.com/PersistenceEAR.

at com.sap.engine.services.deploy.server.application.DeployUtilTransaction.commonBegin(DeployUtilTransaction.java:395)

at com.sap.engine.services.deploy.server.application.DeploymentTransaction.begin(DeploymentTransaction.java:307)

at com.sap.engine.services.deploy.server.application.ApplicationTransaction.makeAllPhasesOnOneServer(ApplicationTransaction.java:290)

... 13 more

Caused by: com.sap.engine.services.deploy.exceptions.ServerDeploymentException: Exception during generation of components of application sap.com/PersistenceEAR in container EJBContainer.

at com.sap.engine.services.deploy.server.application.DeploymentTransaction.makeComponents(DeploymentTransaction.java:609)

at com.sap.engine.services.deploy.server.application.DeployUtilTransaction.commonBegin(DeployUtilTransaction.java:386)

... 15 more

Caused by: java.lang.ClassCastException

at com.sap.engine.services.ejb.deploy.xml.EJBJarParser.processEntity(EJBJarParser.java:291)

at com.sap.engine.services.ejb.deploy.xml.EJBJarParser.processBeans(EJBJarParser.java:206)

at com.sap.engine.services.ejb.deploy.xml.EJBJarParser.parseXml(EJBJarParser.java:152)

at com.sap.engine.services.ejb.deploy.xml.EJBJarParser.parseXml(EJBJarParser.java:97)

at com.sap.engine.services.ejb.deploy.DeployAdmin.parseSingleJar(DeployAdmin.java:297)

at com.sap.engine.services.ejb.deploy.DeployAdmin.generate(DeployAdmin.java:247)

at com.sap.engine.services.ejb.EJBAdmin.deploy(EJBAdmin.java:2133)

at com.sap.engine.services.deploy.server.application.DeploymentTransaction.makeComponents(DeploymentTransaction.java:603)

... 16 more

[Former Member]

To your exceptions:

No idea at all ! Are you sure about correct ejb-jar.xml; what did you say about the PK in there (i.e. <prim-key-class>java.lang.Integer</prim-key-class> FULLY QUALIFIED class name ?

Did you try to deploy on i.e. JBoss (phsst) ? I had the phenomenon that sth. not deployable using JCo on WebAS Sneak Preview works fine with other vendors without any change (aside of DDs).

That does not help you directly in this case but could give a hint where to look for the problem.

Anyway, SLSB or SFSB still might be well worth to take into consideration.

Regards

Matthias

[Former Member]

Quite interesting... Could you please tell me where you found these examples ? JCO is considered here as back-end for BMP ?

[bernd_roedel]

Hello,

no I have NOT found anything yet. I LOOKING FOR examples. For BMP in general and BMP with JCO in particular.

Best regards

Bernd