The problem is that endDocument is actually called twice.  I set
buf=null to cause an exception to be raised on the first call and here
is the backtrace:

Exception in thread "main" java.lang.NullPointerException
	at java.io.FileOutputStream.writeBytes(Native Method)
	at java.io.FileOutputStream.write(Compiled Code)
	at com.jclark.xsl.sax.XMLOutputHandler.flushBuf(Compiled Code)
	at com.jclark.xsl.sax.XMLOutputHandler.endDocument(Compiled Code)
	at com.jclark.xsl.sax.ResultBase.end(Compiled Code)
	at com.jclark.xsl.sax.ExtensionHandlerImpl$2.emit(Compiled Code)
	at com.jclark.xsl.sax.MultiNamespaceResult.resultTreeFragment(Compiled Code)
	at com.jclark.xsl.sax.ExtensionHandlerImpl$1.append(Compiled Code)
	at com.jclark.xsl.tr.CopyOfAction.invoke(Compiled Code)
	at com.jclark.xsl.tr.AppendAction.invoke(Compiled Code)
	at com.jclark.xsl.tr.LiteralElementAction.invoke(Compiled Code)
	at com.jclark.xsl.tr.AppendAction.invoke(Compiled Code)
	at com.jclark.xsl.tr.SheetImpl$ProcessContextImpl.processSafe(Compiled Code)
	at com.jclark.xsl.tr.SheetImpl.process(Compiled Code)
	at com.jclark.xsl.sax.XSLProcessorImpl.parse(Compiled Code)
	at com.jclark.xsl.sax.Driver.transform(Compiled Code)
	at com.jclark.xsl.sax.Driver.transformFile(Compiled Code)
	at com.jclark.xsl.sax.Driver.main(Compiled Code)

I definitely don't understand the implementation well enough yet to
attempt a fix :-)

Cheers,

-- 
Dr. Denys Duchier			Denys.Duchier@xxxxxxxxxxxx
Forschungsbereich Programmiersysteme	(Programming Systems Lab)
Universitaet des Saarlandes, Geb. 45	http://www.ps.uni-sb.de/~duchier
Postfach 15 11 50			Phone: +49 681 302 5618
66041 Saarbruecken, Germany		Fax:   +49 681 302 5615


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