There are only a few preferences for XSLT Portlet. An example portlet definition can be found here.
The contentService preference dictates where the XML source is located.
The two options for this preference are:
classpathContentServicehttpContentService
The location preference is either a path on the WebProxyPortlet classpath
or a URL to the XML source. Examples are:
/test-content/sample.xmlhttp://localhost:8080/sample.xml
The mainXslt preference is the URI to the XSLT source. This can be either
on the classpath or web. To source on the classpath, the format is different
from location. Examples:
classpath:/test-content/sample.xslhttp://localhost:8080/sample.xsl
While this preference is still implemented, support for "mobile" views has
been superseded by responsive design rather than mobile views. It follows
the same conventions as mainXslt.
The preInterceptors preference is used to configure additional features
in httpContentService if specified above. Interceptors provide support
for dynamic location URL parameters and authentication.
See /docs/wpp_usage.md