Java SAX parser Exception : Provider org.apache.xerces.jaxp.SAXParserFactoryImpl could not be instantiated:

Hello ..I am trying to implement a Java SAX parser for my application but I am encountering a SAX error when I am instantiating  the parser itself ..could you help me wth this ,..

Exception in thread "main" javax.xml.parsers.FactoryConfigurationError: Provider org.apache.xerces.jaxp.SAXParserFactoryImpl could not be instantiated: java.lang.NullPointerException
        at javax.xml.parsers.SAXParserFactory.newInstance(SAXParserFactory.java:113)
        at ParseXML.parseTheXml(ParseXML.java:146)
        at ParseXML.main(ParseXML.java:122)



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import org.xml.sax.*;
import org.xml.sax.helpers.*;

import javax.xml.parsers.*;
import org.xml.sax.*;
import org.xml.sax.helpers.*;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.util.StringTokenizer;



public class ParseXML extends DefaultHandler{
      
      public static String geneid="";
      
      
      public void startDocument(  ) throws SAXException {
        System.out.println("Parsing begins...");
      }


      public void endDocument(  ) throws SAXException {
        System.out.println("...Parsing ends.");
}
      
      public void startElement(String namespaceUri,
            String localName,
            String qualifiedName,
            Attributes attributes) throws SAXException {
            
            
             for (int i=0; i<attributes.getLength(  ); i++)
             {
                 // System.out.println("  Attribute: " + attributes.getLocalName(i) +
                 //                    "=" + attributes.getValue(i));          
      
                   if(attributes.getLocalName(i).equals("accession") && attributes.getValue(i).equals(geneid))

                   {
                         System.out.println("I was sucessful in the first part\n");
                         System.out.println("This geneId is found "+geneid);
                         System.exit(1);
                   }
                  
             }
      
      
      }
            
            
      
      
      
      
      public void endElement(String namespaceUri,
            String localName,
            String qualifiedName) throws SAXException {}
      


      public void characters(char[] chars,
            int startIndex,
            int endIndex) {}

      
      
      
      public static void main(String[] args) {
        
            String xmlFile="";
            String inputFile="";
            String outputFile="";
            String leftOutFile ="";
            String line="";
            
            String jaxpPropertyName =
            "javax.xml.parsers.SAXParserFactory";
          
          if (System.getProperty(jaxpPropertyName) == null) {
            String apacheXercesPropertyValue =
              "org.apache.xerces.jaxp.SAXParserFactoryImpl";
            System.setProperty(jaxpPropertyName,
                               apacheXercesPropertyValue);
          }
          
        
          if (args.length == 2) {
                xmlFile = args[0];
                inputFile=args[1];
                outputFile=inputFile+"_" +"GOAnnotated";
                leftOutFile=inputFile+"_" +"Unannotated";
                
          } else {
            
                System.out.println("Usage: java ParseXML [xml file] [geneidfile]");
                System.exit(1);
          
          }
        
      
          // Get the ID from the input file
          
          try
          {
                 BufferedReader br = new BufferedReader(
                        new InputStreamReader(new FileInputStream(inputFile)));
                
                 line = br.readLine(); // Assumes the first Line has the Header
                 int count =0;
                  while ((line = br.readLine()) != null) {
                    
                      if(line!="")
                      {
                            count++;
                            line=line.trim();
                            geneid=line;
                            //Send the ID to the XML parser and parse the file
                            System.out.println("This is id "+count + geneid);
                            parseTheXml(line,xmlFile);
                            if(count==20)
                            {
                                  System.exit(1);
                            }
                      }
                      else
                            continue;
                        
                  }
                
          }catch(Exception e)
          {
                e.printStackTrace();
          }
          
          
      
      }//ends main
      
        
        public static void parseTheXml(String geneId,String xmlFile)
        {
              DefaultHandler handler = new ParseXML();
              SAXParserFactory factory = SAXParserFactory.newInstance();
             
              try {
                  SAXParser parser = factory.newSAXParser();
                  parser.parse(xmlFile, handler);
                } catch(Exception e) {
                  String errorMessage =
                    "Error parsing " + xmlFile + ": " + e;
                  System.err.println(errorMessage);
                  e.printStackTrace();
                }
             
        }


}//ends class
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