beckchr/staxon

weblogic

Closed this issue · 10 comments

mheijink commented

Used the library in a gwt app. It works in hosted mode but when I deploy it on a weblogic server it doesn't. Any suggestions?

beckchr commented

Can you give more details? What does "it doesn't work" mean?

mheijink commented

When I call writer.add(reader) an XMLStreamException: Cannot end document
is thrown.

beckchr commented
  1. What version of StAXON are you using?
  2. Can you post some code snippet?
  3. Would you please post the exception's stack trace?
mheijink commented

1.I'm using staxon-1.1

  1. public static String toJSon(String str, String prefix) {
Logger logger = Logger.getLogger(Conversion.class);

logger.info("Starting toJson with : " + str);

String json = null;
InputStream input = null;
OutputStream output = new ByteArrayOutputStream();

JsonXMLConfig config = new JsonXMLConfigBuilder().autoArray(true).prettyPrint(true).build();

try {

    input = new ByteArrayInputStream(str.getBytes("UTF-8"));
    logger.info("Created a inputstream");

    XMLEventReader reader = XMLInputFactory.newInstance().createXMLEventReader(input);

    JsonXMLOutputFactory outputFactory = new JsonXMLOutputFactory(config);
    outputFactory.setProperty(JsonXMLOutputFactory.PROP_NAMESPACE_DECLARATIONS, false);

    XMLEventWriter writer = outputFactory.createXMLEventWriter(output);
    logger.info("Created a writer");

    /*
     * Copy events from reader to writer.
     */
    writer.add(reader);
    logger.info("Added a reader to writer");

    reader.close();

    writer.flush();
    json = output.toString();

    json = json.replaceAll(prefix + ":", "");

    writer.close();
} catch (UnsupportedEncodingException e) {
    logger.info("UnsupportedEncodingException: " + e.getMessage());
} catch (XMLStreamException e) {
    logger.info("XMLStreamException: " + e.getMessage());
} catch (FactoryConfigurationError e) {
    logger.info("FactoryConfigurationError: " + e.getMessage());
} finally {
    /*
     * As per StAX specification, XMLEventReader/Writer.close() doesn't
     * close the underlying stream.
     */
    try {
        output.close();
        input.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

}

return json;

}

  1. Stack trace : I'm gonna check if I can get more then "Cannnot end document'
mheijink commented

INFO di sep 25 16:50:28.888 2012 XMLStreamException: de.odysseus.staxon.base.AbstractXMLStreamWriter.writeEndDocument(AbstractXMLStreamWriter.java:320)
INFO di sep 25 16:50:28.888 2012 XMLStreamException: de.odysseus.staxon.json.JsonXMLStreamWriter.writeEndDocument(JsonXMLStreamWriter.java:274)
INFO di sep 25 16:50:28.889 2012 XMLStreamException: de.odysseus.staxon.event.SimpleXMLEventWriter.add(SimpleXMLEventWriter.java:57)
INFO di sep 25 16:50:28.889 2012 XMLStreamException: de.odysseus.staxon.event.SimpleXMLEventWriter.add(SimpleXMLEventWriter.java:119)
INFO di sep 25 16:50:28.889 2012 XMLStreamException: nl.tudelft.server.Conversion.toJSon(Conversion.java:131)
INFO di sep 25 16:50:28.890 2012 XMLStreamException: nl.tudelft.server.MyServletContextListener.contextInitialized(MyServletContextListener.java:23)
...

beckchr commented

Thanks. This seems to be a bug in WebLogic's StAX implementation. I guess you don't have a XML declaration (<?xml ...>) in your input, right? The reader does not create a START_DOCUMENT event but an END_DOCUMENT event.

Possible Solutions

  • deploy a better StAX implementation, e.g. woodstox (if you deployed BEA's jsr-173-*.jar, get rid of it)
  • add an XML declaration to your XML
  • add the START_DOCUMENT manually like this:
if (!reader.peek().isStartDocument()) { // this should be there, but...
    writer.add(XMLEventFactory.newInstance().createStartDocument());
}
mheijink commented

Hi Christoph,

I got it working.
I added woodstoz-core-asl-4.1.4 and stax2-api-3.1.1 to my project
And I told weblogic to use these jars by adding

<prefer-web-inf-classes>true</prefer-web-inf-classes>

to the weblogic.xml

Thanks!

beckchr commented

Great!

Anyway, I think I've found the cause now... Using BEA's original StAX implementation (jsr173-1.0-ri.jar), I replaced the

writer.add(reader);

with

System.out.println(reader.getClass());
while (reader.peek() != null) {
    XMLEvent event = reader.nextEvent();
    System.out.println(event);
    writer.add(event);
}

and got the following output:

class com.bea.xml.stream.XMLEventReaderBase
[Stax Event #7]
[Stax Event #1]
[Stax Event #2]
[Stax Event #8]
[Stax Event #8] <-- Second END_DOCUMENT

That is, the peek() method reports zombie END_DOCUMENT events instead of null (as required by the specification).

etenorio87 commented

Hello @mheijink I know you solved this long time ago, but It would be possible you provide me your solution. I recently ran into the same problem when traying to convert xml to json in OSB.