Error while transforming XSLT by calling function with Reflection API

Question

Hi,
I'm new to Reflection API. I want to call function from the jar file which is not in my application context. So I have loaded that jar ( say XXX.jar) file at runtime with URLClassLoader and call the function say [ *myTransform(Document document)* ]. Problem is that when I want to transform any XSLT file in that function it throws exception 'Could not compile stylesheet'. All required classes are in XXX.jar.
If I call 'myTransform' function directly without reflection API then it transformation successfully completed.
Following is code of reflection to invoke function
        ClassLoader contextCL = Thread.currentThread().getContextClassLoader();
        URLClassLoader loader = new URLClassLoader(jarURLs, contextCL);
        Class c = loader.loadClass(fullClasspath);
        Constructor constructor = c.getDeclaredConstructor(constructorParamsClasses);
        Object instance = constructor.newInstance(constructorParams);
        Method method = c.getDeclaredMethod("myTransform", methodParamsClasses);
        Object object = method.invoke(instance, methodParams);Following is function to be called with reflection API.
public Document myTransform ( Document document ) {
// Reference of Document (DOM NODE) used to hold the result of transformation.
            Document doc = null ;
            // DocumentBuilderFactory instance which is used to initialize DocumentBuilder to create newDocumentBuilder.
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance () ;
            // Reference of DocumentBuilder used to create new Document (DOM NODE).
            DocumentBuilder builder;
            try {
                  // Initialize DocumentBuilder by using DocumentBuilderFactory instance.
                  builder = factory.newDocumentBuilder ();
                  // Initialize new document instance by using DocumentBuilder instance.
                  doc = builder.newDocument () ;
                  // Creates new DOMSource by using document (DOM NODE) which is coming through current transform() method parameter.
                  DOMSource domsource = new DOMSource ( document ) ;
                  // Creates new instance of TransformerFactory.
                  TransformerFactory transformerfactory = TransformerFactory.newInstance () ;
                  // Creates new Transformer instance by using TransformerFactory which holds XSLT file.
                  Transformer transformer = null;
********* exception is thrown from here onward ******************
                  transformer = transformerfactory.newTransformer (new StreamSource (xsltFile));
                  // Transform XSLT on document (DOM NODE) and store result in doc (DOM NODE).
                  transformer.transform ( domsource , new DOMResult ( doc ) ) ;
            } catch (ParserConfigurationException ex) {
                  ex.printStackTrace();
            } catch (TransformerConfigurationException ex) {
                  ex.printStackTrace();
            } catch (TransformerException ex) {
                 ex.printStackTrace();
            } catch (Exception ex) {
                 ex.printStackTrace();
            //holds result of transformation.
            return doc ;
}Following is full exception stacktrace
ERROR:  'The first argument to the non-static Java function 'myBeanMethod' is not a valid object reference.'
FATAL ERROR:  'Could not compile stylesheet'
javax.xml.transform.TransformerConfigurationException: Could not compile stylesheet
        at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:829)
        at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl.newTransformer(TransformerFactoryImpl.java:623)
        at com.actl.dxchange.utilities.Transformation.transform(Transformation.java:83)
        at com.actl.dxchange.base.BaseConnector.transform(BaseConnector.java:330)
        at com.actl.dxchange.connectors.KuoniConnector.doRequestProcess(KuoniConnector.java:388)
        at com.actl.dxchange.connectors.KuoniConnector.hotelAvail(KuoniConnector.java:241)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        ...........

Answer 1

Hi,
Thanks for response.
Following is code for setting 'methodParamsClasses' array object. I do ensure that Document is not null and valid. My application is web application.
Document requestObj = /* my code for generating Document object*/
Object[] methodParams = new Object[]{requestObj}
Class[] methodParamsClasses = new Class[]{};
            if (methodParams != null) {
                methodParamsClasses = new Class[methodParams.length];
                for (int i = 0; i < methodParams.length; i++) {
                    if (methodParams[i] instanceof Document) {
/************** if parameter is instance of Document then I set class type as "Document.class" ***********/
                        methodParamsClasses[i] = Document.class;
                    } else {
                        methodParamsClasses[i] = methodParams.getClass();