How to pass a Document object as a parameter to XSLT

I am executing a XSLT from Java using this code ::

        DocumentBuilder builder;
        InputStream defInputStream = this.getClass().getClassLoader().getResourceAsStream("definitionsdb.xml");
        Document definitionsDB = builder.parse(defInputStream);

            Source xslSource = new StreamSource(inputXMLFile);
            Result xmlResult = new StreamResult(xmlOutputFileWriter);
            xmlTransformer.setParameter("inputFile", definitionsDB);
            xmlTransformer.transform(xslSource, xmlResult);

As you can see, apart from the StreamSource input xml file, I am sending another XML file as a parameter to the XSLT.

I receive the file in XSLT using the <xsl:param name="inputFile"/>

But then, I am not able to use the variable as a normal nodeset variable... like $inputFile/Definition/node1 ...

Any solution, on how to solve it?