Birt Classloader problem!!!

I'm working on a J2EE application (which deploys on jboss).We've written some java classes for working with database (and hibernate also).so I've developed a birt oda extension to use this classes.When we're gonna generate reports (with all-in-one) our plugin uses a webservice to send/receive data to/from server.But when we're gonna deploy reports in server and render them,it shouldn't use webservice.Beacuse classes are here.But I'll take noClassDefFound because of the classloading scenario(I think!) 
Is there any solution to my problem?take care that I cannot build and use a jar file from my classes because they may change in every deployment.I think I should be able to set my plugin classloader to my application classloader,but how?? 
I've check so many posts in this issue like (<a class='bbc_url' href='http://www.birt-exchange.org/forum/deploying-integrating-birt-report-engine-applications/14022-problem-deploying-java-event-handlers.html'>http://www.birt-exchange.org/forum/deploying-integrating-birt-report-engine-applications/14022-problem-deploying-java-event-handlers.html</a> ) .ButI don't know what this line means and how it may help: 
config.getAppContext().put(EngineConstants.APPCONTEXT_CLASSLOADER_KEY, yourclass.class.getClassLoader()); 
 
Thanks for your help!

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JasonW

This line
config.getAppContext().put(EngineConstants.APPCONTEXT_CLASSLOADER_KEY, yourclass.class.getClassLoader());

Has to do with if you are writting your own Servlet/Program to use the BIRT APIs. If you are using the viewer this should be the default.

As a test open the config.ini in the WEB-INF/platform/configuration directory and add this line:

osgi.parentClassloader=fwk

This is not a good solution but should help diagnose the issue.

Jason

alirezaS

I use my own program and birt api to render the report(not the viewer) so this issue may be considered for me!
Can you please describe little more about this line:

osgi.parentClassloader=fwk

or May you help me where and who I should ask about this problem?

JasonW

If you are using the api this line:
config.getAppContext().put(EngineConstants.APPCONTEXT_CLASSLOADER_KEY, yourclass.class.getClassLoader());

Should work. The fwk setting will cause the a much bigger classpath and longer class load times.

Jason

alirezaS

Thanks for your replies Jason!
I've tested it and it didn't help me.
Let me explain a bit more.I've put the platform(and plugins and so and so...) in WEB-INF directory of my war file (which deploys in jboss server).I think first of all there is an instance of eclipse loaded which secondly loads birt plugins and also my own oda extension plugin.So there are many classloaders here and I cannot figure out how and which one I should change or set to my application calssloader for loading my classes.

JasonW

Do any reports run? Can you try a report that uses the sample db?
This line:
config.getAppContext().put(EngineConstants.APPCONTEXT_CLASSLOADER_KEY, yourclass.class.getClassLoader());
Try adding whatever class starts up the Engine in the yourclass field.

Jason

alirezaS

Yes.I can run reports with my own oda extension but I have to use a webservice for calling the classes.But for large amount of data it(webservice approach) may fail.
I've tested your code so many times and it cannot help.It seems that it won't change anything.Is there any way I can know eclipse's classloader when it runs?or my plugin's?

JasonW

if your classes are in the cp of the class that instaniates the engine and you have the parent setting there it should be able to access them. Did you try:
osgi.parentClassloader=fwk for testing purposes? You should also be able to add hard paths to your plugins cp for testing as well.

alirezaS

I've tested osgi.parentClassloader=fwk and it didn't help me!
I'm going to think about another approach.Is there anyway I can get the query of my report and run it myself and then give the results to birt for my report execution???(Can I set the resultset of a report when rendering it in my application??)

Thank you very much for your help and attention!

JasonW

Is there any chance you could open a bug and submit your code? The scenario you trying should work.

Jason

alirezaS

I've opened one bug but yet nobody answered me.

Do you know how can I use this line:

config.setOSGiArguments(arguments);

I think it may help me!!!

Thanks

JasonW

In your ODA what is the value of your setThreadContextClassLoader? 
 
 
On the setOSGiArguments some are reserved. It expects a string array. I believe this is setting=value. You can also use a map. 
 
public void setOSGiArguments( String[] arguments ) 
{ 
properties.put( OSGI_ARGUMENTS, arguments ); 
} 
 
/** 
* set the configuration used by the OSGi framework. The configuration 
* includes all valid osgi configs except some reserved as follow: 
* 
[*]1. osgi.install.area, using the one defined by BIRT_HOME. 
* 
[*]2. eclipse.ignoreApp, be true. 
* 
[*]3. osgi.noShutDown, be true. 
* 
[*]4. osgi.framework, using the one defined by BIRT_HOME 
* 
[*]5. osgi.framework.useSystemProperties, be false. 
* 
* @param osgiConfigMap 
*/ 
public void setOSGiConfig( Map osgiConfigMap ) 
{ 
properties.put( OSGI_CONFIGURATION, osgiConfigMap ); 
} 
 
Jason

alirezaS

What do you think it should be?(setThreadContextClassLoader)I have no idea how to pass my classloader into my oda plugin????

My question about osgi argument is:What are these arguements?How can I know about them???

Thanks for your attention a lot!!!

alirezaS

What do you think it should be?(setThreadContextClassLoader)I have no idea how to pass my classloader into my oda plugin????

My question about osgi argument is:What are these arguments?How can I know about them???

Thanks for your attention a lot!!!

JasonW

I wrote an ODA for hibernate that I set it to true. I also added to the cp using a URL class loader. The source for it is here: 
<a class='bbc_url' href='http://www.actuate.com/products/resources/?articleid=11719'>Actuate BIRT Community Contributions</a> 
 
Also from the extension description 
 
setThreadContextClassLoader - If true, the consumer of the ODA runtime extension plug-in should set the thread context class loader to the one used to load this driver before calling any ODA interface method. Any data source plug-in extension with this flag set to true would take precedence, and is applied to all data source extensions implemented by this plug-in. 
If the thread context class loader being set is the OSGi class loader that was used to load this ODA runtime plugin, it is not designed to be used by a plugin to in turn load additional classes. If further class loading is needed, it is up to individual ODA runtime plugin implementation to provide its own URLClassLoader, and switch thread context class loader as appropriate. 
 
OSGi arguments: 
Look at this 
<a class='bbc_url' href='http://help.eclipse.org/ganymede/index.jsp?topic=/org.eclipse.platform.doc.isv/reference/misc/runtime-options.html'>Help - Eclipse SDK</a> 
 
scroll down to system properties for a description of each. 
 
Jason

alirezaS

Thank you very much,Jason.

With a combination of setThreadContextClassLoader = true and osgi.parentClassloader = fwk my problem has been solved.

Thank you again.