Re: [Jython-users] Classpath/Classloader issue with Jython invoke d vi a Tomcat/Velocity

[Alexey N. S. <A.S...@md...>]

Tomcat handles all class loading. Please make sure that there is no 
jython.jar on a global classpath. Maybe your launcher (for example 
JBuilder) puts it onto Tomcat's classpath.

- Alexey.

Travis Bear wrote:

>Alexey, 
>
>For this webapp, jython.jar is installed in
>$CATALINA_HOME/webapps/$WEBAPP_NAME/WEB-INF/lib/ 
>
>If you are correct, is there a recommended way to override the
>classloader with one of my choosing? 
>
>
>Thanks! 
>
>
>-Travis 
>
>
>On Jan 31, 2005, at 2:55 PM, Alexey N. Solofnenko wrote: 
>
>
>  
>
>> I think it indicates that your code is loaded by another (global?)
>>class loader. Where do you have Jython jar installed? 
>>
>> - Alexey. 
>>
>> Travis Bear wrote: 
>>I'm really puzzled by an issue I'm seeing running Jython.  I've
>>compiled 
>>my scripts with jythonc into java class files.  These scripts import 
>>some classes from external jar files.  From the command line,
>>everything 
>>runs just fine.  However, when I invoke the Jython scripts  from
>>inside 
>>Tomcat, they break because they can't locate any of the packages I try
>>
>>to import from.  The puzzling part is that other (non-Jython) code in
>>my 
>>webapp imports the same pacakges just fine, and it's all running in
>>the 
>>same VM.  
>>
>>Here is the Jython script Setup.py:  
>>
>>print "Entering Setup"  
>>
>>from org.jtmb.sql import DataEngine  
>>from java.io import File  
>>
>>propsFile = File("conf/DataEngine.properties")  
>>de = DataEngine.getStaticInstance(propsFile)  
>>print de.getString("select version as name from branch")  
>>
>>Here is the code from the Velocity context where I statically invoke
>>the 
>>jython script:  
>>
>>com.myrio.setup.Setup.main(new String[]{});  
>>
>>Here's an alternate effort in the Velocity context where I try to 
>>explicitly use the same classloader:  
>>
>>    ClassLoader loader = this.getClass().getClassLoader();  
>>    Object setup = Class.forName("com.myrio.setup.Setup", true,  
>>loader).newInstance();  
>>    logger.fatal ("Attempting to load setup with custom classloader");
>>
>>    ((com.myrio.setup.Setup) setup).main(new String[]{});  
>>
>>
>>In both cases, I get the same result.  Here's the output in 
>>catalina.out.  
>>
>>Entering Setup  
>>Traceback (innermost last):  
>>  File "/home/travis/p4/3.5/qa/qas/code/jython/Setup.py", line 0, in 
>>main  
>>ImportError: No module named jtmb  
>>
>>
>>
>>Thanks in advance -- this is my first effort at using classloaders, so
>>I 
>>could easily be missing something.  I'm pretty sure I could get it to 
>>work by manually setting the classpath via system properties.  But
>>that 
>>seems like a pretty broken approach.  Any help is appreciated!  
>>
>>
>>-Travis  
>>
>>   
>>
>>
>> --  
>>
>> Alexey N. Solofnenko 
>> home: http://trelony.cjb.net/ 
>>  
>> _________________________________________________ Scanned on 31 Jan
>>2005 22:57:33
>>
>>    
>>