'com.fasterxml.aalto.impl.StreamExceptionBase: Can not output XML declaration, after other output has already been done.' when trying to transform XML using XSLT

[nestrada]

Hello,

I wanted to test out the performances of aalto so I wrote this simple test program where I indent some XML using an XSLT stylesheet and use StaXSources and StaXResults as the input and output of the Transformer respectively.

Here is my test code:

public static void main(String[] args) throws Exception {

    SAXTransformerFactory xformerFactory = (SAXTransformerFactory) TransformerFactory
            .newInstance();

    InputStream is = null;

    is = XMLTest.class.getResourceAsStream("/xml/indenter.xsl");
    Templates indenter = xformerFactory.newTemplates(new StreamSource(is));
    is.close();

    System.out.println(indenter);

    File xml = new File(args[0]);
    File outXml = new File(args[0] + ".out");

    // XMLInputFactory xif = XMLInputFactory.newFactory(
    // "com.sun.xml.internal.stream.XMLInputFactoryImpl", XMLTest.class.getClassLoader());
    XMLInputFactory xif = XMLInputFactory.newFactory(
            "com.fasterxml.aalto.stax.InputFactoryImpl", XMLTest.class.getClassLoader());

    xif.setProperty(XMLInputFactory.IS_COALESCING, Boolean.TRUE);
    xif.setProperty(XMLInputFactory.IS_NAMESPACE_AWARE, Boolean.TRUE);
    System.out.println(xif);
    // XMLOutputFactory xof = XMLOutputFactory.newFactory(
    // "com.sun.xml.internal.stream.XMLOutputFactoryImpl", XMLTest.class.getClassLoader());
    XMLOutputFactory xof = XMLOutputFactory.newFactory(
            "com.fasterxml.aalto.stax.OutputFactoryImpl", XMLTest.class.getClassLoader());
    System.out.println(xof);

    Source in = new StAXSource(xif.createXMLStreamReader(new FileInputStream(xml)));
    Result out = new StAXResult(
            xof.createXMLStreamWriter(new FileOutputStream(outXml), "UTF-8"));

    indenter.newTransformer().transform(in, out);
    // xformerFactory.newTransformer().transform(in, out);

}

And I get the exception visible in the title. Any help would be suggested.

Nicolas

[nestrada]

An additional note, when I comment the indenter.newTransformer().transform() and replace it with the line below (ie. a pass through transformer), I get the following exception:

ERREUR : 'com.fasterxml.aalto.impl.StreamExceptionBase: Trying to declare prefix xmlns (illegal as per NS 1.1 #4)'
Exception in thread "main" javax.xml.transform.TransformerException: javax.xml.stream.XMLStreamException: com.fasterxml.aalto.impl.StreamExceptionBase: Trying to declare prefix xml
ns (illegal as per NS 1.1 #4)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:719)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:313)
at xml.XMLTest.main(XMLTest.java:78)
Caused by: javax.xml.stream.XMLStreamException: com.fasterxml.aalto.impl.StreamExceptionBase: Trying to declare prefix xmlns (illegal as per NS 1.1 #4)
at com.sun.org.apache.xalan.internal.xsltc.trax.StAXStream2SAX.handleCharacters(StAXStream2SAX.java:266)
at com.sun.org.apache.xalan.internal.xsltc.trax.StAXStream2SAX.bridge(StAXStream2SAX.java:171)
at com.sun.org.apache.xalan.internal.xsltc.trax.StAXStream2SAX.parse(StAXStream2SAX.java:120)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transformIdentity(TransformerImpl.java:656)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:707)
... 2 more

[nestrada]

Whoops I forgot to show the stacktrace for the first exception

ERREUR : 'com.fasterxml.aalto.impl.StreamExceptionBase: Can not output XML declaration, after other output has already been done.'
Exception in thread "main" javax.xml.transform.TransformerException: com.sun.org.apache.xalan.internal.xsltc.TransletException: com.fasterxml.aalto.impl.StreamExceptionBase: Can no
t output XML declaration, after other output has already been done.
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:713)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:313)
at xml.XMLTest.main(XMLTest.java:77)
Caused by: com.sun.org.apache.xalan.internal.xsltc.TransletException: com.fasterxml.aalto.impl.StreamExceptionBase: Can not output XML declaration, after other output has already b
een done.
at com.sun.org.apache.xalan.internal.xsltc.dom.SAXImpl.characters(SAXImpl.java:1564)
at com.sun.org.apache.xalan.internal.xsltc.dom.DOMAdapter.characters(DOMAdapter.java:330)
at GregorSamsa.applyTemplates()
at GregorSamsa.template$dot$0()
at GregorSamsa.applyTemplates()
at GregorSamsa.applyTemplates()
at GregorSamsa.transform()
at com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet.transform(AbstractTranslet.java:602)
at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:709)
... 2 more

I would be happen to attach the indenter.xsl XSLT stylesheet, but I can't seem to paste it here. Note however that it works fine using the standard XML input and output factories.

[cowtowncoder]

Hmmh. I suspect that indentation calls are what cause problems (since writing output for indentation could be taken as output preceding xml declaration).

I'll see if I can figure out what gives...

[cowtowncoder]

Can not reproduce without an example.