Here's some more information about the call that's failing:
https://xerces.apache.org/xerces2-j/javadocs/api/javax/xml/validation/SchemaFactory.html#newInstance(java.lang.String)
If that's behaving oddly and it can't figure out what classes to use, can you specify for it using this?
https://xerces.apache.org/xerces2-j/javadocs/api/javax/xml/validation/SchemaFactory.html#newInstance(java.lang.String,%20java.lang.String,%20java.lang.ClassLoader)
To find out what value to use for factoryClassName, try just getting the name of the class that's generated successfully when you run in the UI. After:
def sf = SchemaFactory.newInstance("http://www.w3.org/XML/XMLSchema/v1.1");simply:
log.info sf.class
You could try also importing that class specifically in your constructor or in your assertion script etc.
