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Manas Ahlaad

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Recent posts by Manas Ahlaad

I am using Quartz as scheduler for an application deployed on WebSphere 4.0 . I dont see any issues if WebSphere server is on Windows NT machine, but if I deploy it on an UNIX machine ( AIX ) I get SimpleThreadPool - Classcast exception

more specifically
========================


[3/16/05 14:47:32:927 GMT+00:00] 376e4a65 SystemOut U 2005-03-16 14:47:32,922 [ORB.thread.pool:2] ERROR com.honeywell.eac.admin.ejb.AdminGeneralManagerBean - ThreadPool class 'org.quartz.simpl.SimpleThreadPool' could not be instantiated.
org.quartz.SchedulerException: ThreadPool class 'org.quartz.simpl.SimpleThreadPool' could not be instantiated. [See nested exception: java.lang.ClassCastException: org.quartz.simpl.SimpleThreadPool]
at org.quartz.impl.StdSchedulerFactory.instantiate(StdSchedulerFactory.java:462)
at org.quartz.impl.StdSchedulerFactory.getScheduler(StdSchedulerFactory.java:837)
at com.honeywell.eac.adhocquery.scheduler.AdhocQuerySchedulerManager.getAdhocQueryScheduler(AdhocQuerySchedulerManager.java:53)
at com.honeywell.eac.adhocquery.scheduler.AdhocQuerySchedulerManagerServlet.init(AdhocQuerySchedulerManagerServlet.java:64)
at javax.servlet.GenericServlet.init(GenericServlet.java:258)
at com.ibm.servlet.engine.webapp.StrictServletInstance.doInit(ServletManager.java:802)
at com.ibm.servlet.engine.webapp.StrictLifecycleServlet._init(StrictLifecycleServlet.java:141)
at com.ibm.servlet.engine.webapp.PreInitializedServletState.init(StrictLifecycleServlet.java:254)
at com.ibm.servlet.engine.webapp.StrictLifecycleServlet.init(StrictLifecycleServlet.java(Inlined Compiled Code))
at com.ibm.servlet.engine.webapp.ServletInstance.init(ServletManager.java(Compiled Code))
at javax.servlet.GenericServlet.init(GenericServlet.java(Inlined Compiled Code))
at com.ibm.servlet.engine.webapp.ServletManager.addServlet(ServletManager.java(Compiled Code))
at com.ibm.servlet.engine.webapp.WebAppServletManager.loadServlet(WebAppServletManager.java(Compiled Code))
at com.ibm.servlet.engine.webapp.WebAppServletManager.loadAutoLoadServlets(WebAppServletManager.java(Compiled Code))
at com.ibm.servlet.engine.webapp.WebApp.loadServletManager(WebApp.java:1217)
at com.ibm.servlet.engine.webapp.WebApp.init(WebApp.java:145)
at com.ibm.servlet.engine.srt.WebGroup.loadWebApp(WebGroup.java:259)
at com.ibm.servlet.engine.srt.WebGroup.init(WebGroup.java:168)
at com.ibm.servlet.engine.ServletEngine.addWebApplication(ServletEngine.java:857)
at com.ibm.ws.runtime.WebContainer.install(WebContainer.java:43)
at com.ibm.ws.runtime.Server.startModule(Server.java:617)
at com.ibm.ejs.sm.active.ActiveModule.startModule(ActiveModule.java:511)
at com.ibm.ejs.sm.active.ActiveModule.startAction(ActiveModule.java:355)
at com.ibm.ejs.sm.active.ActiveObject.startObject(ActiveObject.java:722)
at com.ibm.ejs.sm.active.ActiveObject.start(ActiveObject.java:131)
at com.ibm.ejs.sm.active.ActiveObject.operateOnContainedObjects(ActiveObject.java:622)
at com.ibm.ejs.sm.active.ActiveEJBServer.startAction(ActiveEJBServer.java:735)
at com.ibm.ejs.sm.active.ActiveObject.startObject(ActiveObject.java:722)
at com.ibm.ejs.sm.active.ActiveObject.start(ActiveObject.java:131)
at java.lang.reflect.Method.invoke(Native Method)
at com.ibm.ejs.sm.agent.AdminAgentImpl.activeObjectInvocation(AdminAgentImpl.java:93)
at com.ibm.ejs.sm.agent.AdminAgentImpl.invokeActiveObject(AdminAgentImpl.java:62)
at com.ibm.ejs.sm.agent._AdminAgentImpl_Tie._invoke(_AdminAgentImpl_Tie.java:73)
at com.ibm.CORBA.iiop.ExtendedServerDelegate.dispatch(ExtendedServerDelegate.java:532)
at com.ibm.CORBA.iiop.ORB.process(ORB.java:2450)
at com.ibm.CORBA.iiop.OrbWorker.run(OrbWorker.java:186)
at com.ibm.ejs.oa.pool.ThreadPool$PooledWorker.run(ThreadPool.java:104)
at com.ibm.ws.util.CachedThread.run(ThreadPool.java:144)
* Nested Exception (Underlying Cause) ---------------
java.lang.ClassCastException: org.quartz.simpl.SimpleThreadPool
at org.quartz.impl.StdSchedulerFactory.instantiate(StdSchedulerFactory.java:460)
at org.quartz.impl.StdSchedulerFactory.getScheduler(StdSchedulerFactory.java:837)
at com.honeywell.eac.adhocquery.scheduler.AdhocQuerySchedulerManager.getAdhocQueryScheduler(AdhocQuerySchedulerManager.java:53)
at com.honeywell.eac.adhocquery.scheduler.AdhocQuerySchedulerManagerServlet.init(AdhocQuerySchedulerManagerServlet.java:64)
at javax.servlet.GenericServlet.init(GenericServlet.java:258)
at com.ibm.servlet.engine.webapp.StrictServletInstance.doInit(ServletManager.java:802)
at com.ibm.servlet.engine.webapp.StrictLifecycleServlet._init(StrictLifecycleServlet.java:141)
at com.ibm.servlet.engine.webapp.PreInitializedServletState.init(StrictLifecycleServlet.java:254)
at com.ibm.servlet.engine.webapp.StrictLifecycleServlet.init(StrictLifecycleServlet.java(Inlined Compiled Code))
at com.ibm.servlet.engine.webapp.ServletInstance.init(ServletManager.java(Compiled Code))
at javax.servlet.GenericServlet.init(GenericServlet.java(Inlined Compiled Code))
at com.ibm.servlet.engine.webapp.ServletManager.addServlet(ServletManager.java(Compiled Code))
at com.ibm.servlet.engine.webapp.WebAppServletManager.loadServlet(WebAppServletManager.java(Compiled Code))
at com.ibm.servlet.engine.webapp.WebAppServletManager.loadAutoLoadServlets(WebAppServletManager.java(Compiled Code))
at com.ibm.servlet.engine.webapp.WebApp.loadServletManager(WebApp.java:1217)
at com.ibm.servlet.engine.webapp.WebApp.init(WebApp.java:145)
at com.ibm.servlet.engine.srt.WebGroup.loadWebApp(WebGroup.java:259)
at com.ibm.servlet.engine.srt.WebGroup.init(WebGroup.java:168)
at com.ibm.servlet.engine.ServletEngine.addWebApplication(ServletEngine.java:857)
at com.ibm.ws.runtime.WebContainer.install(WebContainer.java:43)
at com.ibm.ws.runtime.Server.startModule(Server.java:617)
at com.ibm.ejs.sm.active.ActiveModule.startModule(ActiveModule.java:511)
at com.ibm.ejs.sm.active.ActiveModule.startAction(ActiveModule.java:355)
at com.ibm.ejs.sm.active.ActiveObject.startObject(ActiveObject.java:722)
at com.ibm.ejs.sm.active.ActiveObject.start(ActiveObject.java:131)
at com.ibm.ejs.sm.active.ActiveObject.operateOnContainedObjects(ActiveObject.java:622)
at com.ibm.ejs.sm.active.ActiveEJBServer.startAction(ActiveEJBServer.java:735)
at com.ibm.ejs.sm.active.ActiveObject.startObject(ActiveObject.java:722)
at com.ibm.ejs.sm.active.ActiveObject.start(ActiveObject.java:131)
at java.lang.reflect.Method.invoke(Native Method)
at com.ibm.ejs.sm.agent.AdminAgentImpl.activeObjectInvocation(AdminAgentImpl.java:93)
at com.ibm.ejs.sm.agent.AdminAgentImpl.invokeActiveObject(AdminAgentImpl.java:62)
at com.ibm.ejs.sm.agent._AdminAgentImpl_Tie._invoke(_AdminAgentImpl_Tie.java:73)
at com.ibm.CORBA.iiop.ExtendedServerDelegate.dispatch(ExtendedServerDelegate.java:532)
at com.ibm.CORBA.iiop.ORB.process(ORB.java:2450)
at com.ibm.CORBA.iiop.OrbWorker.run(OrbWorker.java:186)
at com.ibm.ejs.oa.pool.ThreadPool$PooledWorker.run(ThreadPool.java:104)
at com.ibm.ws.util.CachedThread.run(ThreadPool.java:144)




Is there a jdk or websphere specific class called SimpleThreadPool that conflicts with Quartz specific SimpleThreadPool and throwing classcast exception ?

To avoid this, where do I put quartz.jar file so that WebSphere always takes SimpleThreadPool inside Quartz jar and doesnt throw Class Cast Exception . Please help.

Thanks in advance
13 years ago
if we set bean scope to <b> page </b> and , will the bean be available once refresh the page ?

[Bear: edited title to remove nonsensical typos]
[ May 24, 2004: Message edited by: Bear Bibeault ]
14 years ago
JSP
I have been breaking my head since one week to come up with a novel solution for the following problem:
Lets take a typical database schema. It contains number of tables, of which ,
... some have primary key/foreign key relation ship,
... there can be one or more tables which mediate to form a relation between two tables.
User has a requirement like this:
He should be given UI such that he will have the option to select some from a series of business attributes .These attributes which will map to database columns.
He can select attributes in such a fashion that
... some of the attributes may be columns of two tables which has primary/foreign key relationship
... some of the attributes from disjoint tables which will be linked indirectly through one or more tables
Taking all these into consideration,
if user submits the Search , we have to form a query based on above and give the user resultant records.
We have to avoid resulting cartesian product (It results when there is no join or filter)
How do you look at such kind of system ??
We proposed user to use Crystal Reports. But user doesnt want to get exposed/fall in the risk of understanding the database structure. He just wants a system where in he can select business fields (with out applying his domain knowledge as to whether these fields logically relate or not) and he wants to get results.
Any help/views are appreciated.
To My Knowledge, ejbpostcreate is a call back method by ejb container. If you override that method in bean class, container will execute that once bean has come to ready state.
I agree that there is not much activity in corba group where as in web services , technologies are up to data and compatible with latest
specifications.
Is the area of application different for Corba and Web Services ??
From the discussion above , I perceive that there is no clear cut difference.
please let me know your comments.
14 years ago
Someboday has said, if you use EJB's ,objects will be pooled by container and given to you as and when you need them. But what's the point ,I still use DAO's , Servlet's. container will pool only EJB objects. How will that improve/effect my performance ??
For my application , Business logic is written in Database Views. So do I still need one more layer between DAO and Servlets??
Please let me know your comments.
Can CORBA IDL be an alternative to Web Services
please clarify
14 years ago
Though ,I couldnt get satisfactory answer , your comments were helpful. Thanks guys !
14 years ago
I am doing desing for a web based reporting application. I use JSP for view , servlets for controller and then DAO's for talking to database. Value Objects carry information back and forth. I user application server's Data Source for getting connections via thin driver.
Number of records in each table that I talk to are in lakhs.
If I introduce Session beans between servlets and DAO , how will I get benefited ?
Will it increase performance in any way ?
Do we need session bean if there are no entity beans in the application
Please clarify.
Someone was asking me as to why people choose Web Service architecture if CORBA IDL is there.
please debate.
14 years ago
I am doing desing for a web based reporting application. I use JSP for view , servlets for controller and then DAO's for talking to database. Value Objects carry information back and forth. I user application server's Data Source for getting connections via thin driver.
Number of records in each table that I talk to are in lakhs.
If I introduce Session beans between servlets and DAO , how will I get benefited ?
Will it increase performance in any way ?
Please clarify.
Why should a controller be a servlet , why not a JSP ? why is it mentioned in all the framesworks like Structs, MVC that servlet is controller.
please clarify
14 years ago
Kyle , Lasse ..
Please help me .
I am admidst of real trouble
Manas
I am have deployed an existing application on my VAJ .this has got vap classses.
When I tried running the application , i got VAPReadFailure Exception - can not read from database.
Do I need to map the models to datastore ?Do I have to configure VAP models as we do for EJB's.
please help.
Where can I get information on VAP on VAJ 3.02. When I tried compiling some EJB's which were using VAP API.(error is missing supporting classes).
Where can I get information on them?
TIA
Manas