TransformerException

Question

I have the following method with transforms my XML using an XSLT file. I get an javax.xml.transform.TransformException: java.lang.nullPointerException on the line
transformer = tFactory.newTransformer(xsltSource);
I know that it is finding my xslt file okay and can read it as I test this using the File.canRead() method. Any ideas on why I am getting this exception?
public void outputXSL(PrintWriter out) {
Document document = createXMLDocument();
// Make the input sources for the XML and XSLT documents
Source xmlSource = new DOMSource(document);
// XSL input, check file can be read
File file = new File("c:\\ServletsWorking\\MS.xsl");
System.out.println("Read from File: " + file.canRead());
StreamSource xsltSource = new StreamSource(file);
// output response to printwriter of HTTPResponse object
StreamResult xmlResult = new StreamResult(out);
TransformerFactory tFactory = TransformerFactory.newInstance();
Transformer transformer = null;
try {
//Get a XSLT transformer
transformer = tFactory.newTransformer(xsltSource);
} catch(TransformerConfigurationException e) {
e.printStackTrace();
try{
transformer.transform(xmlSource, xmlResult);
} catch(TransformerException e) {
e.printStackTrace();
}

Answer 1

Your code seems to be correct and it should work. But the way canRead() is used is more related to the IO accesability than not to the security constrains. I mean, you get true because there are not security restrictions, not because it is physically possible to read. Did you try to read from a file that is unconditionally unused?
Also try checking xsltSource:
if(xsltSource != null)
  try {
    //Get a XSLT transformer
    transformer = tFactory.newTransformer(xsltSource);
  } catch(TransformerConfigurationException e) {
    e.printStackTrace();
  }I'm not sure if my english is good enough, so if you don't understand my answer, excuse me.