Creating Threads in EJBs

Hi,
I know that you are not allowed to create threads inside EJBs. However, can an EJB call some java networking code that creates threads for its purpose?
In other words, how far does this prohibition on threads go? You can't even call some code that creates threads inside an EJB or is it that you just can't create threads inside the EJB class itself?
Thanks,
Y.

I know that you are not allowed to create threads
inside EJBs. However, can an EJB call some java
networking code that creates threads for its
purpose?Although the specs don't allow you, they don't completely rule out the possibility.
In other words, how far does this prohibition on
threads go? You can't even call some code that
creates threads inside an EJB or is it that you just
can't create threads inside the EJB class itself?
http://www.theserverside.com/discussions/thread.tss?thread_id=31118This discussion should throw some light.

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E:\Oracle\Middleware\jdeveloper\system\system11.1.1.0.31.51.56\DefaultDomain\bin\startWebLogic.cmd
[waiting for the server to complete its initialization...]
JAVA Memory arguments: -Xms256m -Xmx512m -XX:CompileThreshold=8000 -XX:PermSize=48m -XX:MaxPermSize=128m
WLS Start Mode=Development
CLASSPATH=;e:\Oracle\MIDDLE~1\patch_wls1030\profiles\default\sys_manifest_classpath\weblogic_patch.jar;e:\Oracle\MIDDLE~1\patch_jdev1111\profiles\default\sys_manifest_classpath\weblogic_patch.jar;e:\Oracle\MIDDLE~1\patch_cie660\profiles\default\sys_manifest_classpath\weblogic_patch.jar;e:\Oracle\MIDDLE~1\JDK160~1\lib\tools.jar;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\weblogic_sp.jar;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\weblogic.jar;e:\Oracle\MIDDLE~1\modules\features\weblogic.server.modules_10.3.0.0.jar;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\webservices.jar;e:\Oracle\MIDDLE~1\modules\ORGAPA~1.5/lib/ant-all.jar;e:\Oracle\MIDDLE~1\modules\NETSFA~1.0_1/lib/ant-contrib.jar;;E:\Oracle\MIDDLE~1\WLSERV~1.3\common\eval\pointbase\lib\pbclient57.jar;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\xqrl.jar;;
PATH=e:\Oracle\MIDDLE~1\patch_wls1030\profiles\default\native;e:\Oracle\MIDDLE~1\patch_jdev1111\profiles\default\native;e:\Oracle\MIDDLE~1\patch_cie660\profiles\default\native;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\native\win\32;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\bin;e:\Oracle\MIDDLE~1\modules\ORGAPA~1.5\bin;e:\Oracle\MIDDLE~1\JDK160~1\jre\bin;e:\Oracle\MIDDLE~1\JDK160~1\bin;C:\oracle\product\10.2.0\client_1\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;G:\D\JACKYH\Installed\apache-ant-1.7.1\bin;C:\Program Files\TortoiseSVN\bin;C:\Program Files\CollabNet Subversion;U:.;V:.;E:\Oracle\MIDDLE~1\WLSERV~1.3\server\native\win\32\oci920_8
* To start WebLogic Server, use a username and *
* password assigned to an admin-level user. For *
* server administration, use the WebLogic Server *
* console at http:\\hostname:port\console *
starting weblogic with Java version:
java version "1.6.0_05"
Java(TM) SE Runtime Environment (build 1.6.0_05-b13)
Java HotSpot(TM) Client VM (build 10.0-b19, mixed mode)
Starting WLS with line:
e:\Oracle\MIDDLE~1\JDK160~1\bin\java -client -Xms256m -Xmx512m -XX:CompileThreshold=8000 -XX:PermSize=48m -XX:MaxPermSize=128m -DproxySet=false -Djbo.34010=false -Xverify:none -da -Dplatform.home=E:\Oracle\MIDDLE~1\WLSERV~1.3 -Dwls.home=E:\Oracle\MIDDLE~1\WLSERV~1.3\server -Dweblogic.home=E:\Oracle\MIDDLE~1\WLSERV~1.3\server -Dweblogic.management.discover=true -Dwlw.iterativeDev= -Dwlw.testConsole= -Dwlw.logErrorsToConsole= -Dweblogic.ext.dirs=e:\Oracle\MIDDLE~1\patch_wls1030\profiles\default\sysext_manifest_classpath;e:\Oracle\MIDDLE~1\patch_jdev1111\profiles\default\sysext_manifest_classpath;e:\Oracle\MIDDLE~1\patch_cie660\profiles\default\sysext_manifest_classpath -Dweblogic.Name=DefaultServer -Djava.security.policy=E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\weblogic.policy weblogic.Server
<12/11/2008 10:54:31 AM EST> <Notice> <WebLogicServer> <BEA-000395> <Following extensions directory contents added to the end of the classpath:
E:\Oracle\Middleware\patch_wls1030\profiles\default\sysext_manifest_classpath\weblogic_ext_patch.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\beehive_ja.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\beehive_ko.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\beehive_zh_CN.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\beehive_zh_TW.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\p13n_wls_ja.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\p13n_wls_ko.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\p13n_wls_zh_CN.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\p13n_wls_zh_TW.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\testclient_ja.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\testclient_ko.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\testclient_zh_CN.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\testclient_zh_TW.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\tuxedocontrol_ja.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\tuxedocontrol_ko.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\tuxedocontrol_zh_CN.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\tuxedocontrol_zh_TW.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\workshop_ja.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\workshop_ko.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\workshop_zh_CN.jar;E:\Oracle\Middleware\wlserver_10.3\L10N\workshop_zh_TW.jar>
<12/11/2008 10:54:32 AM EST> <Info> <WebLogicServer> <BEA-000377> <Starting WebLogic Server with Java HotSpot(TM) Client VM Version 10.0-b19 from Sun Microsystems Inc.>
<12/11/2008 10:54:32 AM EST> <Info> <Management> <BEA-141107> <Version: WebLogic Server Temporary Patch for CR380042 Thu Sep 11 13:33:40 PDT 2008
WebLogic Server Temporary Patch for 7372756 Fri Sep 12 17:05:44 EDT 2008
WebLogic Server 10.3 Mon Aug 18 22:39:18 EDT 2008 1142987 >
<12/11/2008 10:54:33 AM EST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to STARTING>
<12/11/2008 10:54:33 AM EST> <Info> <WorkManager> <BEA-002900> <Initializing self-tuning thread pool>
<12/11/2008 10:54:34 AM EST> <Notice> <Log Management> <BEA-170019> <The server log file E:\Oracle\Middleware\jdeveloper\system\system11.1.1.0.31.51.56\DefaultDomain\servers\DefaultServer\logs\DefaultServer.log is opened. All server side log events will be written to this file.>
<12/11/2008 10:54:36 AM EST> <Notice> <Security> <BEA-090082> <Security initializing using security realm myrealm.>
<12/11/2008 10:54:38 AM EST> <Warning> <Deployer> <BEA-149617> <Non-critical internal application uddi was not deployed. Error: [Deployer:149158]No application files exist at 'E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\uddi.war'.>
<12/11/2008 10:54:38 AM EST> <Warning> <Deployer> <BEA-149617> <Non-critical internal application uddiexplorer was not deployed. Error: [Deployer:149158]No application files exist at 'E:\Oracle\MIDDLE~1\WLSERV~1.3\server\lib\uddiexplorer.war'.>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to STANDBY>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to STARTING>
<12/11/2008 10:54:39 AM EST> <Notice> <Log Management> <BEA-170027> <The Server has established connection with the Domain level Diagnostic Service successfully.>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to ADMIN>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to RESUMING>
<12/11/2008 10:54:39 AM EST> <Notice> <Server> <BEA-002613> <Channel "Default[1]" is now listening on 127.0.0.1:7101 for protocols iiop, t3, ldap, snmp, http.>
<12/11/2008 10:54:39 AM EST> <Notice> <Server> <BEA-002613> <Channel "Default" is now listening on 192.168.12.54:7101 for protocols iiop, t3, ldap, snmp, http.>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000331> <Started WebLogic Admin Server "DefaultServer" for domain "DefaultDomain" running in Development Mode>
<12/11/2008 10:54:39 AM EST> <Warning> <Server> <BEA-002611> <Hostname "jackyh.dst.com.au", maps to multiple IP addresses: 192.168.12.54, 127.0.0.1>
<12/11/2008 10:54:39 AM EST> <Warning> <Server> <BEA-002611> <Hostname "localhost", maps to multiple IP addresses: 192.168.12.54, 127.0.0.1>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000365> <Server state changed to RUNNING>
<12/11/2008 10:54:39 AM EST> <Notice> <WebLogicServer> <BEA-000360> <Server started in RUNNING mode>
DefaultServer startup time: 13829 ms.
DefaultServer started.
[Running application SessionEJB on Server Instance DefaultServer...]
---- Deployment started. ---- 12/11/2008 10:54:43
Target platform is (Weblogic 10.3).
Running dependency analysis...
2008-11-12 10:54:43.882: Writing EJB JAR file to E:\Oracle\Middleware\jdeveloper\system\system11.1.1.0.31.51.56\o.j2ee\drs\SessionEJB\SessionEJB-Project1-ejb
2008-11-12 10:54:43.914: Wrote EJB JAR file to E:\Oracle\Middleware\jdeveloper\system\system11.1.1.0.31.51.56\o.j2ee\drs\SessionEJB\SessionEJB-Project1-ejb
2008-11-12 10:54:44.148: Writing EAR file to E:\Oracle\Middleware\jdeveloper\system\system11.1.1.0.31.51.56\o.j2ee\drs\SessionEJB
2008-11-12 10:54:44.164: Wrote EAR file to E:\Oracle\Middleware\jdeveloper\system\system11.1.1.0.31.51.56\o.j2ee\drs\SessionEJB
Deploying Application...
<12/11/2008 10:54:46 AM EST> <Error> <Deployer> <BEA-149265> <Failure occurred in the execution of deployment request with ID '1226447686226' for task '0'. Error is: 'weblogic.management.DeploymentException: '
weblogic.management.DeploymentException:
     at weblogic.application.internal.flow.BaseLifecycleFlow$CreateListenerAction.run(BaseLifecycleFlow.java:171)
     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
     at weblogic.security.service.SecurityManager.runAs(Unknown Source)
     at weblogic.application.internal.flow.BaseLifecycleFlow$BaseAction.invoke(BaseLifecycleFlow.java:99)
     at weblogic.application.internal.flow.HeadLifecycleFlow.createListener(HeadLifecycleFlow.java:117)
     Truncated. see log file for complete stacktrace
java.lang.ClassNotFoundException: oracle.security.jps.wls.listeners.JpsApplicationLifecycleListener
     at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:283)
     at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:256)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
     at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:176)
     Truncated. see log file for complete stacktrace
>
<12/11/2008 10:54:46 AM EST> <Warning> <Deployer> <BEA-149004> <Failures were detected while initiating deploy task for application 'SessionEJB'.>
<12/11/2008 10:54:46 AM EST> <Warning> <Deployer> <BEA-149078> <Stack trace for message 149004
weblogic.management.DeploymentException:
     at weblogic.application.internal.flow.BaseLifecycleFlow$CreateListenerAction.run(BaseLifecycleFlow.java:171)
     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
     at weblogic.security.service.SecurityManager.runAs(Unknown Source)
     at weblogic.application.internal.flow.BaseLifecycleFlow$BaseAction.invoke(BaseLifecycleFlow.java:99)
     at weblogic.application.internal.flow.HeadLifecycleFlow.createListener(HeadLifecycleFlow.java:117)
     Truncated. see log file for complete stacktrace
java.lang.ClassNotFoundException: oracle.security.jps.wls.listeners.JpsApplicationLifecycleListener
     at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:283)
     at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:256)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
     at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:176)
     Truncated. see log file for complete stacktrace
>
[Deployer:149034]An exception occurred for task [Deployer:149026]deploy application SessionEJB on DefaultServer.: .
weblogic.management.DeploymentException:
#### Deployment incomplete. #### 12/11/2008 10:54:46
oracle.jdeveloper.deploy.DeployException
     at oracle.jdevimpl.deploy.common.Jsr88RemoteDeployer.doDeploymentAction(Jsr88RemoteDeployer.java:247)
     at oracle.jdevimpl.deploy.common.Jsr88RemoteDeployer.deployImpl(Jsr88RemoteDeployer.java:157)
     at oracle.jdeveloper.deploy.common.AbstractDeployer.deploy(AbstractDeployer.java:94)
     at oracle.jdevimpl.deploy.fwk.WrappedDeployer.deployImpl(WrappedDeployer.java:39)
     at oracle.jdeveloper.deploy.common.AbstractDeployer.deploy(AbstractDeployer.java:94)
     at oracle.jdeveloper.deploy.common.BatchDeployer.deployImpl(BatchDeployer.java:82)
     at oracle.jdeveloper.deploy.common.AbstractDeployer.deploy(AbstractDeployer.java:94)
     at oracle.jdevimpl.deploy.fwk.WrappedDeployer.deployImpl(WrappedDeployer.java:39)
     at oracle.jdeveloper.deploy.common.AbstractDeployer.deploy(AbstractDeployer.java:94)
     at oracle.jdevimpl.deploy.fwk.DeploymentManagerImpl.deploy(DeploymentManagerImpl.java:436)
     at oracle.jdeveloper.deploy.DeploymentManager.deploy(DeploymentManager.java:209)
     at oracle.jdevimpl.runner.adrs.AdrsStarter$4$1.run(AdrsStarter.java:1316)
Caused by: oracle.jdeveloper.deploy.DeployException
     at oracle.jdevimpl.deploy.common.Jsr88DeploymentHelper.deployApplication(Jsr88DeploymentHelper.java:413)
     at oracle.jdevimpl.deploy.common.Jsr88RemoteDeployer.doDeploymentAction(Jsr88RemoteDeployer.java:238)
     ... 11 more
Caused by: oracle.jdeveloper.deploy.DeployException: Deployment Failed
     at oracle.jdevimpl.deploy.common.Jsr88DeploymentHelper.deployApplication(Jsr88DeploymentHelper.java:395)
     ... 12 more
#### Cannot run application SessionEJB due to error deploying to DefaultServer.
[Application SessionEJB stopped and undeployed from Server Instance DefaultServer]

Steve,
I'm facing the same issue as user#####.
Your workaround does not work ; when I deploy manuelly the ear file, with a new weblogic-application.xml, I get the same error.
Does that happen a lot ? :p
Edit :
my web.xml :
<?xml version = '1.0' encoding = 'windows-1252'?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5" xmlns="http://java.sun.com/xml/ns/javaee">
<description>Empty web.xml file for Web Application</description>
<context-param>
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</context-param>
<context-param>
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</context-param>
<context-param>
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<filter>
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    <filter-class>oracle.security.jps.ee.http.JpsFilter</filter-class>
</filter>
<filter>
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    <filter-class>org.apache.myfaces.trinidad.webapp.TrinidadFilter</filter-class>
</filter>
<filter>
    <filter-name>adfBindings</filter-name>
    <filter-class>oracle.adf.model.servlet.ADFBindingFilter</filter-class>
</filter>
<filter-mapping>
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    <servlet-name>Faces Servlet</servlet-name>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>REQUEST</dispatcher>
    <dispatcher>INCLUDE</dispatcher>
</filter-mapping>
<filter-mapping>
    <filter-name>trinidad</filter-name>
    <servlet-name>Faces Servlet</servlet-name>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>REQUEST</dispatcher>
</filter-mapping>
<filter-mapping>
    <filter-name>adfBindings</filter-name>
    <servlet-name>Faces Servlet</servlet-name>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>REQUEST</dispatcher>
</filter-mapping>
<servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet>
    <servlet-name>resources</servlet-name>
    <servlet-class>org.apache.myfaces.trinidad.webapp.ResourceServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>/faces/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>resources</servlet-name>
    <url-pattern>/adf/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>resources</servlet-name>
    <url-pattern>/afr/*</url-pattern>
</servlet-mapping>
<session-config>
    <session-timeout>35</session-timeout>
</session-config>
<mime-mapping>
    <extension>html</extension>
    <mime-type>text/html</mime-type>
</mime-mapping>
<mime-mapping>
    <extension>txt</extension>
    <mime-type>text/plain</mime-type>
</mime-mapping>
</web-app>Luc-
Edited by: Lucas Ismag on 4 déc. 2008 05:33

Exception in creating message-driven ejb : [java.lang.NullPointerException]

[#|2008-09-17T07:32:06.973-0500|SEVERE|sun-appserver-ee8.2|javax.enterprise.system.container.ejb.mdb|_ThreadID=58;|MDB00050: Message-driven bean [OAHMSTcpIpServer1:eaTCPIP_cmTcpIpServer_Service1]: Exception in creating message-driven ejb : [java.lang.NullPointerException]|#]
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|#]

Hello,
If I make use of the @EJB annotation again a NullPointerException is risen
package videoclub;
import java.awt.Component;
import java.awt.Container;
import java.awt.FocusTraversalPolicy;
import java.util.Vector;
import javax.annotation.Resource;
import javax.ejb.EJB;
import javax.swing.JOptionPane;
import vc.bl.ClerkSessionRemote;
import vc.domain.Customer;
* @author IOANNIS_PAPAIOANNOU
@EJB(name="ejb/ClerkSessionBean", beanInterface=ClerkSessionRemote.class, beanName="ClerkSessionBean")
public class Clerk extends javax.swing.JFrame
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} The line:
ClerkSessionRemote clerkSessionBean = (ClerkSessionRemote) sessionContext.lookup("ejb/ClerkSessionBean");rises the exception
the output of the client:
init:
init:
deps-jar:
compile:
library-inclusion-in-archive:
Building jar: C:\Documents and Settings\IOANNIS_PAPAIOANNOU\My Documents\NetBeansProjects\VideoClub\VideoClub-ejb\dist\VideoClub-ejb.jar
dist:
deps-jar:
compile-single:
run-single:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
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at videoclub.Clerk$2.run(Clerk.java:232)
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at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
BUILD SUCCESSFUL (total time: 2 seconds)
Yiannis P.

How to create a local EJB 3.0 and execute in JDeveloper?

Hello guys!
I'm brand new with EJB 3.0.
I would like to know how can I create a @Local EJB and a client in JDeveloper?
It's was ease to create a @Remote EJB and the sample java client, how can I do same to @Local EJB?
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Creating a @Local EJB is just as easy, just replace the @Remote by @Local, or checkmark local in the EJB wizard.
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If you want to test the local methods of an ejb, you should create another ejb which calls the first.

How to create a deployable ejb(.jar file) when we use Oracle application sever?

Hi,
In case if we use Weblogic we give following command on console to create a deployable ejb, while weblogic.jar is in classpath.
java weblogic.ejbc temp.jar StudentBean.jar
1)What are the classes or jar files we have to set in classpath,
2)What console based command(like what I mentioned above for weblogic) can we use,
so that we can create a deployable jar file in case if we are using Oracle application server.
thanks,
Milind

You can discover the origins of a loaded class programatically. You want to print:
TheClass.class.getProtectionDomain().getCodeSource().getLocation().toString();

Error Code -17400; Unable to create thread

Running TestStand 4.0. Test sequence calls many sequences that run as new executions and runs fine for up to about 8 units testing simultaneously. After that, I get a run-time error code -17400; Unable to create thread. There are no other details available. The steps that generate the error are able to create the new executions initially, but eventually fail once about 22 executions are running. I am monitoring memory resources and there does not appear to be any issues. Any troubleshooting suggestions? Thanks.

My test sequence has several test groups, each of which contain loops that create new threads (tests) for 48 UUTs. Thus the number of running threads does get very high. I was running into problems with Windows XP GDI Object resources once the number of threads reached about 200. I then modified my program into smaller test groups to keep the number of threads at any time to less than 150. GDI resources are no longer an issue, but the error -17400 unable to create thread happens after the first test group has completed and the second test group is just trying to run. Note that the second test group runs fine if I skip the first test group, so the sequence itself should be okay. I thought it might be a memory issue (even though there are no apparent memory issues seen in Windows Task Manager), so I set the "Unload after step executes" property for each of the new executions created. That did not resolve the issue.
I am trying to create a simple sequence to duplicate the error without using any of the actual test sequences that require test hardware, but have not been successful thus far.
Thanks for your replies and suggestions!

Create Thread on Photoshop Plug-in

Dear All,
Right now, I am developing a demo Photoshop plug-in software to understand the way to implement Photoshop plug-in. However, I meet a issues that I can not create a Thread on Photoshop plug-in by CreateThread() API. I implement as below:
Main function:
CreateThread( NULL, 0, Test1Thread, NULL, 0, NULL);
Thread function:
DWORD WINAPI Test1Thread(LPVOID pParam)
/*Do something*/
return 0;
When I compile and load plug-in on Photoshop, it show an error message like this:
The instruction at "0x09fd100a" referenced memory at "0x09fd100a". The memory could not be "read"
Click on OK to terminate the program
Click on CANCEL to debug the program
Can you give me some suggestions that I can create a Thread by CreateThread() API on Photoshop plug-in or not? And how can I create Thread?
I am looking forward your answer.
Thanks for your help,
Hieu Nguyen.
PS: I am developing on Window OS and Visual C++ development tool.

Thanks Aandi Inston and Marcus Phillips for your answer.
In thread I just use Named Pipe inter-process communication mechanism to send signal to the other application. So I do not use any Photoshop API.
However, it is strange that I can not put my Thread in begin of PluginMain function:
DLLExport SPAPI SPErr PluginMain
( char* caller, char* selector, void* message)
SPErr error = kSPNoError;
SPMessageData *basicMessage = NULL;
SPPluginRef plugInRef = NULL;
SPErr err = 0;
basicMessage = (SPMessageData *) message;
sSPBasic = basicMessage->basic;
gPlugInRef = basicMessage->self;
MyThread();/*CAN NOT RUN THE THREAD!!!!*/
I must change my Thread function to position after checking caller parameter
Please show me the reason why?
Thanks,

Why are there 2 methods to create thread ?

Hi,
To create threads, there are two methods
1) Inherit the THREAD super-class
2) Implement the interface RUNNABLE.
The reason for providing two methods is that, the user can only one level of "implementation inheritance". That is the reason, which comes immediately to mind. But is there another reason(s)? If yes, than what is the reason??
Any help would be welcome
Thanks in advance

I was one of those authors. We all read some other
author who said the same dumb thing LOL, been there, done that, you have my sympathy :-)
Could you explain your use of the words "policy" and
"mechanism"? I completely agree with your conclusion,
but don't really understand your argument.This is one of the things that I've taken from my experiences with the X Window System (tm, I think). "Mechanism, not policy" was one of the mantras that would be repeated by every author. As I understood it, the idea was that the X protocol, Xlib, and even Xt prescribed the mechanism for a program's interaction with windows on a client screen, but did not prescribe how those windows would interact with the user. That was the "policy" to be implemented by the toolkit and application layers (thus the different appearance of Motif, OpenLook, Xaw, &c, even though they used the same underlying code up through the toolkit).
I like the mantra, and as I've come to understand OO programming, I try to apply it as a way to identify what could/should be abstracted and what needs to remain concrete. If something abstracts a basic service that can be used in multiple ways -- like threads -- I consider that mechanism. If something is closely tied to the way my application works, I consider that policy. The former are implemented with interfaces and abstract classes, and do not contain application-specific code; the latter are implemented with instantiable classes.

Not seeing persistEntity or mergeEntity method when creating a session EJB

Hi all,
I am using JDev 11g to develop an ADF application. I have finished creating an entity EJB from database tables. Then I want to create a session EJB. In JDev, I do not see persistEntity or mergeEntity method in "<Core Facade Methods>"; rather, I am seeing another method
public Object queryByRange(String jpqlStmt,int firstResult,int maxResults)
listed there.
Could you please let me know why? I am expecting to have persistEntity and mergeEntity methods included in the final created session EJB.
Thank you.

Hi,
Thank you for your reply. But I am still not sure how to use the persist and merge methods from EntityManager. Either I want in the session EJB creation wizard to have persistEntity and mergeEntity to appear under "Core Facade methods", or I want to add these methods in the generated bean java file. I tried the latter by adding these two methods in the bean file, but I got an exception at runtime.
Please privide some more information. Thank you very much.

Creating Threads in Java Stored procedures

Can I create threads inside Java Stored procedures?
or is there a restriction?
Thanks
Kal

Can I create threads inside Java Stored procedures?
or is there a restriction?
Thanks
Kal Hi Kal,
I don't mean to be rude, but have you tried it? Personally, I
haven't tried it (since I didn't have the need).
You don't say what version of Oracle DBMS you are using, but I
am using 8.1.7.3 on Solaris 7, and according to Oracle's
"Oracle 8i Java Developer's Guide", there is no restriction
(of-course, that depends on what you call a "restriction" :-)
http://otn.oracle.com/docs/products/oracle8i/doc_library/817_doc/java.817/a83728/03writ11.htm#1003094
Hope this helps.
Good Luck,
Avi.

Listeners, load a class on startup and creating threads in infinite loop

This is an identical post to the one I made in the jsp forum. I do this as I know, being a regular here, that there are equally good people(in j2ee web application development) in both these forum, but many of them stick to their particular forums of choice - jsp / servlets.
I was wondering if there is any means by which I could launch my own class when tomcat starts (in the same jvm).
1. I need one or more Thread/TimerTask because the requirement is such that the application would have continous data drops (in the form of logs) which has to be picked up, parsed and pushed into a db. Another part of the application reads the data from the db on requests (http) and displays it over the web. The thread has to poll for arrival of new logs and then hand it over to a framework for parsing and inserting the parsed data to a db.
2. I know that I can possibly use a servlet with a load-on-startup value greater than 1 and code my requirement into the init method. However, using a servlet for a functionality different from servicing http requests has me worried. (valid ?), not to mention the fact that Iam very uneasy about creating threads from within Servlets.
3. I googled hard and found that I could probably use a tomcat specific context lifecycle listener.
4. I could also possibly use the servlet api - the ServletContextListener.
5. I have rejected #2 and settled on either #3 or #4 - the ServletContextListener or Tomcat specific Lifecycle Listener, though the later, as I said binds me to Tomcat (which is ok for me). Are there any other specific (dis)advantages of using either especially when I have to create threads from within them (on context startup)? Other than memory leaks, killing the thread objects & associated resources on context shutdown, is there anything else that I need to watch out for while using threads.
6. I wonder is there is there a plain startup hook available in tomcat (rather than listeners) - from where I can launch a class that starts a thread in the same jvm as tomcat's ?
Thanks In Advance,
Ram.

Anybody ? Sorry for bumping up.
Thanks,
Ram.

Creating threads in init for servlet (advanced)

Hello
we have a servlet ..in servlets init method we are creating new threads by calling the Timer class like this
BGMSchedul = new Timer(true);
BGM = new BackManager();
BGMSchedul.scheduleAtFixedRate(BGM, 10000, 30000); //every 30 secondsProblem is that during our stress testing on IBM WSAD we've noticed errors like J2CA0075W: An active transaction should be present
Upon researching this issue further i found this link http://www-1.ibm.com/support/docview.wss?rs=180&uid=swg21231761
which i think suggests that the servlet shouldnt be creating threads which make J2C connections. Our thread is making the DB connection.
does nay one have experince with this sort of problem? is it a bad programming construct to create threds in a servlet? if so..where should we be creating our threads? we want this thread to run every 30 seconds and this is a web appliction.
I'd appreciate any help

I've created a POJO class that implements servletcontextlistener and took out the time thread from servlet and placed it in pojo's contextInitialized method. however, i still get the same warning.

Creating threads in Weblogic

For a variety of reasons I need to write my own messaging bridge between Weblogic and MQ. The reasons have been validated by BEA, so I'm not completely off my rocker :)
I can either write this as a standalone java application that acts as a client to weblogic's JMS server, or as a deployed webapp (using the ServletContextListener method to start/stop it). Either way the app will <shudder>create one thread per queue</shudder> and listen on that queue until a message arrives.
The pros of a deployed application (cost-free clustering, management, can use a webapp to manage the threads/queues, etc) leads me in that direction, but creating threads in a J2EE server dubious at best.
Ideally this webapp runs in its own execute queue, and the holy grail is to have the threads run in that execute queue. However, there doesn't seem to be any supported way to create threads from an execute queue.
Has anyone done anything like this? Any suggestions on how to spawn and manage the threads properly? Should it be deployed or stand-alone?
cheers
mike

Hello,
The webapp route sounds better to me than a standalone java app, you will get things up and running a lot more quickly and get all the goodies associated with webapps.
You don't explicity create threads from the queue for example in the way you get connections from a connection pool. Once you have created and configuered your execute queue you just add a few init parameters to your web.xml deployment descriptor:
<servlet>
<servlet-name>MainServlet</servlet-name>
<jsp-file>/myapplication/critical.jsp</jsp-file>
<init-param>
<param-name>wl-dispatch-policy</param-name>
<param-value>CriticalAppQueue</param-value>
</init-param>
</servlet>
see:
http://e-docs.bea.com/wls/docs81/perform/AppTuning.html#1105201
for complete instructions.
cheers
Hussein Badakhchani
www.orbism.com

How to create the simple EJB Applications.

Hi
I have asked about the what are the necessary softwares required for creating the Simple EJB Applications.
I have
Jdk 1.6,
Netbeans 5.5,
J2EE5 ,
Apache Tomcat 5.5
what are other necessary softwares?please tell me From where i get the source code samples?
Please Tell me it is necessary for me..

Hi U,
Tomcat is only JSP/Servlet container -- no EJB support.
Easiest is to download the Netbeans 6.1 bundle including Glassfish and JavaDB, thats all you need + JDK and Java EE of course.
Glassfish has both web/JSP/Servlet-container and EJB-container, so Tomcat is not needed then.
( If for some reason you really want to use Tomcat, you can use it together with OpenEJB for example, to add EJB-support. )

Creating Threads in EJBs

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