Why am I getting a NoClassDefFoundError?

Question

Could anybody tell me why I'm getting this error, and how to fix the problem?

Exception in thread "main" java.lang.NoClassDefFoundError: org/codehaus/stax2/ri/Stax2ReaderAdapter at org.codehaus.staxmate.dom.DOMConverter._build(DOMConverter.java:188) at org.codehaus.staxmate.dom.DOMConverter.buildDocument(DOMConverter.java:171) at org.codehaus.staxmate.dom.DOMConverter.buildDocument(DOMConverter.java:152) at org.codehaus.staxmate.dom.DOMConverter.buildDocument(DOMConverter.java:131) at xmlprocessing.api.STAXModifyCV.main(STAXModifyCV.java:68) Caused by: java.lang.ClassNotFoundException: org.codehaus.stax2.ri.Stax2ReaderAdapter at java.net.URLClassLoader$1.run(URLClassLoader.java:202) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at java.lang.ClassLoader.loadClass(ClassLoader.java:307) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) at java.lang.ClassLoader.loadClass(ClassLoader.java:248) ... 5 more Java Result: 1

I wrote the code below:

    //-*-*-
    FileInputStream input = new FileInputStream("cv.xml");
    XMLStreamReader reader = XMLInputFactory.newInstance().createXMLStreamReader(input);
    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));

    //-*-*- get new entries from input stream
    System.out.println("<< Sahar CV >>\n -> Modify the first reference\n    ** Modify The Name **");
    System.out.print("    Enter degree : ");
    String degree = in.readLine();
    System.out.print("    Enter first name : ");
    String fName = in.readLine();
    System.out.print("    Enter last name : ");
    String lName = in.readLine();
    System.out.println("    ** Modify The Address ** ");
    System.out.print("    Enter new city : ");
    String newCity = in.readLine();
    System.out.print("    Enter new country : ");
    String newCountry = in.readLine();

    //-*-*- let the reader point at the first "reference" element
    int eventType;
    boolean ref = false, fname = false;
    while (!ref && reader.hasNext()) {
        eventType = reader.next();
        switch (eventType) {
            case XMLEvent.START_ELEMENT:
                if (reader.getLocalName().equalsIgnoreCase("references")) {
                    ref = true;
                    break;
                }
        }
    }
    System.out.println("I am here");

    //-*-*- start modification
    Document doc = new DOMConverter().buildDocument(reader);
    Element firstRef = (Element)doc.getElementsByTagName("reference").item(0);
    NodeList name = (NodeList)firstRef.getElementsByTagName("name");
    //-*-*- modify the degree (Dr. , Eng. , Dev. ,etc)
    Attr att = (Attr)name.item(0).getAttributes().item(0);
    ((Node)att).setNodeValue(degree);
    //-*-*- modify first name
    NodeList firstName = (NodeList)firstRef.getElementsByTagName("fname");
    NodeList firstNameChilds = (NodeList)firstName.item(0).getChildNodes();
    ((Node)firstNameChilds.item(0)).setNodeValue(fName);
    //-*-*- modify last name
    NodeList lastName = (NodeList)firstRef.getElementsByTagName("lname");
    NodeList lastNameChilds = (NodeList)lastName.item(0).getChildNodes();
    ((Node)lastNameChilds.item(0)).setNodeValue(lName);
    //-*-*- modify city
    NodeList city = (NodeList)firstRef.getElementsByTagName("city");
    NodeList cityChilds = (NodeList)city.item(0).getChildNodes();
    ((Node)cityChilds.item(0)).setNodeValue(newCity);
    //-*-*- modify country
    NodeList country = (NodeList)firstRef.getElementsByTagName("country");
    NodeList countryChilds = (NodeList)country.item(0).getChildNodes();
    ((Node)countryChilds.item(0)).setNodeValue(newCountry);

    reader.close();
    input.close();
    //-*-*- write DOM document
    FileOutputStream out = new FileOutputStream("cv.xml");
    XMLStreamWriter sw = XMLOutputFactory.newInstance().createXMLStreamWriter(out);

    new DOMConverter().writeDocument(doc, sw);
    sw.close();
    out.close();

Answer 1

You need to make sure the right Woodstox is in your path. Basically, you're using a class that's implemented in that jar, but because the jar isn't in the path Java has no idea what class you're referencing.

Answer 2

This means that a .class file was found that didn't contain the expected class, either because the package doesn't correspond with the directory structure or because the file was renamed after compilation. There are other causes but this is the most common.

Answer 3

Sorry I voted down on the 3 answers but suddenly had a doubt and needed to double check what I thought ... and it ended up being more complex than I thought. However I found a very complete answer for you here: http://mindprod.com/jgloss/runerrormessages.html#NOCLASSDEFFOUNDERROR