Why is the java compiler throwing a NullPointerException?

[phpuser123]

That's what I've implemented...

import java.io.*;
import org.xml.sax.*;
import org.xml.sax.helpers.DefaultHandler;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
public class java_xml extends DefaultHandler{
 
 
    public static void main(String argv[])
    {
 
    // Use an instance of ourselves as the SAX event handler
    DefaultHandler handler = new java_xml();
    // Use the default (non-validating) parser
    SAXParserFactory factory = SAXParserFactory.newInstance();
    try {
    // Set up output stream
    OutputStreamWriter out = new OutputStreamWriter(System.out, "UTF8");
    // Parse the input
    SAXParser saxParser = factory.newSAXParser();
    saxParser.parse( "file.xml", handler );
    } catch (SAXException t) {
    System.err.println(t.getLocalizedMessage()+" Errorzz");
    }
    catch (IOException t) {
        System.err.println(t.getLocalizedMessage()+" Errorzz");
        }
    catch (ParserConfigurationException t) {
        t.printStackTrace();
        }
    System.exit(0);
    }
 
 
 
    static private Writer out;
    private void emit(String s)
    throws SAXException
    {
    try {
    out.write(s);
    out.flush();
    } catch (IOException e) {
    throw new SAXException("I/O error", e);
    }
    }
 
 
 
    private void nl()
    throws SAXException
    {
    String lineEnd = System.getProperty("line.separator");
    try {
    //ECHOING AN XML FILE WITH THE SAX PARSER 129
    out.write(lineEnd);
    } catch (IOException e) {
    throw new SAXException("I/O error", e);
    }
    }
 
 
    public void startDocument()
    throws SAXException
    {
    //emit("<?xml version='1.0' encoding='UTF-8'?>");
    //nl();
        System.out.println("parsing starts");
    }
    public void endDocument()
    throws SAXException 
    {
        System.out.println("parsing Ends");
 
 
    }    
 
 
    public void startElement(String namespaceURI,
            String sName, // simple name
            String qName, // qualified name
            Attributes attrs)
            throws SAXException
            {
            String eName = sName; // element name
            if ("".equals(eName)) eName = qName; // not namespace-aware
            emit("<"+eName);
            if (attrs != null) {
            for (int i = 0; i < attrs.getLength(); i++) {
            String aName = attrs.getLocalName(i); // Attr name
            if ("".equals(aName)) aName = attrs.getQName(i);
            emit(" ");
            emit(aName+"=\""+attrs.getValue(i)+"\"");
            }
            }
            emit(">");
            }
            public void endElement(String namespaceURI,
            String sName, // simple name
            String qName // qualified name
            )
            throws SAXException
            {
            //ECHOING AN XML FILE WITH THE SAX PARSER 131
            String eName = sName; // element name
            if ("".equals(eName)) eName = qName; // not namespace-aware
            emit("</"+eName+">");
            }
}

and my xml file which I name file.xml goes below:

<?xml version='1.0' encoding='UTF-8'?>
<Personnel>
<Employee type="permanent">
        <Name>Seagull</Name>
        <Id>3674</Id>
        <Age>34</Age>
   </Employee>
  <Employee type="contract">
        <Name>Robin</Name>
        <Id>3675</Id>
        <Age>25</Age>
    </Employee>
  <Employee type="permanent">
        <Name>Crow</Name>
        <Id>3676</Id>
        <Age>28</Age>
    </Employee>
</Personnel>

Why am I getting a NullPointerException?The problem is somewhat in my xml file...



Thanks in adv

[Frinavale]

Do you know which line in the above posted code that the error occurs on?



-Frinny

[phpuser123]

On line 42 and 88
BTW here's the stack trace ..

Exception in thread "main" java.lang.NullPointerException
at java_xml.emit(java_xml.java:42)
at java_xml.startElement(java_xml.java:88)
at com.sun.org.apache.xerces.internal.parsers.Abstrac tSAXParser.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTD Validator.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumen tFragmentScannerImpl.scanStartElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumen tScannerImpl$ContentDispatcher.scanRootElementHook (Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumen tFragmentScannerImpl$FragmentContentDispatcher.dis patch(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumen tFragmentScannerImpl.scanDocument(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Co nfiguration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Co nfiguration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLPars er.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.Abstrac tSAXParser.parse(Unknown Source)
at javax.xml.parsers.SAXParser.parse(Unknown Source)
at javax.xml.parsers.SAXParser.parse(Unknown Source)
at java_xml.main(java_xml.java:22)

[dbeberman]

Where is your
static private Writer out;
being initialized?

[phpuser123]

Yes I skipped the initialisaton part..
Thabks, It's working now