DO NOT REPLY [Bug 15240] New: - No locator provided upon stylesheet errors

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http://nagoya.apache.org/bugzilla/show_bug.cgi?id=15240

No locator provided upon stylesheet errors

           Summary: No locator provided upon stylesheet errors
           Product: XalanJ2
           Version: 2.4
          Platform: Other
        OS/Version: Other
            Status: NEW
          Severity: Normal
          Priority: Other
         Component: org.apache.xalan.transformer
        AssignedTo: xalan-dev@xml.apache.org
        ReportedBy: caprani@altern.org
                CC: mmidy@apache.org


Current processing of stylesheet errors does not allow straightforward 
processing like this:
=========
StreamSource source = new StreamSource(source_url);

// A stylesheet with an error, for example
// <xsl:apply_templates/><!-- a '_' in place of a '-' -->
StreamSource stylesheet = new StreamSource(stylesheet_url);

StreamResult result = new StreamResult(System.out);

try {	
	Transformer transformer = factory.newTransformer(stylesheet);

} catch (TransformerConfigurationException tce) {
	// Here we get the error message but not the location where the problem 
occured:
	//   javax.xml.transform.TransformerConfigurationException:
	//   javax.xml.transform.TransformerException:
	//   javax.xml.transform.TransformerException:
	//   xsl:apply_templates is not allowed in this position in the 
stylesheet!
	System.err.println(tce.getMessageAndLocation());
}
=========

The exception that is thrown when parsing an erroneous stylesheet does not 
provide a locator.
The original exception (with its locator) is burried deep into a nesting of 
exceptions.

The TransformerConfigurationException contains:
- A TransformerConfigurationException (no locator) which contains:
  - A TransformerException (no locator) which contains:
    - A SaxException which contains:
      - A TransformerException (with a locator !)

I suggest that at least the SaxException should be avoided, because the SAX 
mechanism should be made transparent. The SaxException that is caught during 
parse() (in TransformerFactoryImpl.newTemplates()) would be unpacked and the 
encapsulated TransformerException be sent to the fatalError
(TransformerException) Handler.

The default ErrorListener may also make sure to provide a locator for the 
exceptions it throws (I've noticed there is an ensureLocationSet(exception) to 
do that).

Note: This is probably similar to bug #5872