Since SAX is only an interface, in order to use it the application must define its implementation. SAX parser implementation in Java can be set via system-property javax.xml.parsers.SAXParserFactory. Since Xerces package was integrated to Java Runtime Envorinment, this implementation is used by default. By this reason, in common case there is no need to specify alternate parsers:

 // creating built-in (default) implementation of SAX:
  SAXParserFactory factory = SAXParserFactory.newInstance();

  // create SAX-parser...
  SAXParser parser = factory.newSAXParser();

  // now we are ready to parse XML data...