Error Obtained while calling a custom java code from RTF template

Hi,
Created a jar file and placed it in /opt/oracle/BI_Middleware/user_projects/domains/bifoundation_domain/lib
created a rtf template and calling the java code as below
<?namespace:cfns=http://www.oracle.com/XSL/Transform/java/com.test.bi.CustomFunctions?&gt;
<?for-each:listOfNames?>
<?cfns:helloFunction(name)?>
<?end for-each?>

Created a data source -xml file which is placed in
/opt/oracle/BI_Middleware/user_projects/domains/bifoundation_domain/config/bipublisher/repository/DemoFiles.

The xml file contains
<customFunctions>
<listOfNames>
<name>Vishal</name>
</listOfNames>
<listOfNames>
<name>Shaili</name>
</listOfNames>
</customFunctions>

But getting the below error :

FOProcessor setLocale: en-us
oracle.xdo.XDOException: java.lang.reflect.InvocationTargetException