public StAXResult(XMLStreamWriter xmlStreamWriter) 
{
        if (xmlStreamWriter == null) {
            throw new IllegalArgumentException("XMLStreamWriter cannot be null.");
        }
        this.xmlStreamWriter = xmlStreamWriter;
        this.xmlEventWriter = null;
}

 public StAXResult(XMLEventWriter xmlEventWriter) 
{
        if (xmlEventWriter == null) {
            throw new IllegalArgumentException("XMLEventWriter cannot be null.");
        }
        this.xmlStreamWriter = null;
        this.xmlEventWriter = xmlEventWriter;
}

 public String getSystemId() 
{
        return null;
}

 public XMLEventWriter getXMLEventWriter() 
{
        return xmlEventWriter;
}

 public XMLStreamWriter getXMLStreamWriter() 
{
        return xmlStreamWriter;
}

 public  void setSystemId(String systemId) 
{
        throw new UnsupportedOperationException("Setting systemId is not supported.");
}