import java.net.*;import javax.xml.parsers.*;import org.xml.sax.*;import org.xml.sax.helpers.*;import org.w3c.dom.*;import com.heaton.bot.*;import java.io.*;/** * Example program from Chapter 6 * Programming Spiders, Bots and Aggregators in Java * Copyright 2001 by Jeff Heaton * * * This example program parses a XML file. This file * may come from either the Internet or a local drive. * * @author Jeff Heaton * @version 1.0 */public class ParseXML {  /** Current indentention */  static private int _indent = 0;  /**   * Display common data for every type of element.   *   * @param n The node.   */  static private void printlnCommon(Node n)  {    System.out.print(" nodeName=\"" + n.getNodeName() + "\"");    String val = n.getNamespaceURI();    if ( val != null )      System.out.print(" uri=\"" + val + "\"");    val = n.getPrefix();    if ( val != null )      System.out.print(" pre=\"" + val + "\"");    val = n.getLocalName();    if ( val != null )      System.out.print(" local=\"" + val + "\"");    val = n.getNodeValue();    if ( val != null ) {      System.out.print(" nodeValue=");      if ( val.trim().equals("") ) {        // Whitespace        System.out.print("[WS]");      } else {        System.out.print("\"" + n.getNodeValue() + "\"");      }    }    System.out.println();  }  /**   * Indent the proper number of spaces for the display.   */  static private void doIndentation()  {    for ( int i = 0; i < _indent; i++ )      System.out.print("  ");  }  /**   * Display an idividual node. Called recursivly.   *   * @param n   */  static private void display(Node n)  {    // Indent to the current level before printing anything    doIndentation();    int type = n.getNodeType();    switch ( type ) {    case Node.ATTRIBUTE_NODE:      System.out.print("ATTR:");      printlnCommon(n);      break;    case Node.CDATA_SECTION_NODE:      System.out.print("CDATA:");      printlnCommon(n);      break;    case Node.COMMENT_NODE:      System.out.print("COMM:");      printlnCommon(n);      break;    case Node.DOCUMENT_FRAGMENT_NODE:      System.out.print("DOC_FRAG:");      printlnCommon(n);      break;    case Node.DOCUMENT_NODE:      System.out.print("DOC:");      printlnCommon(n);      break;    case Node.DOCUMENT_TYPE_NODE:      System.out.print("DOC_TYPE:");      printlnCommon(n);      // Print entities if any      NamedNodeMap nodeMap = ((DocumentType)n).getEntities();      _indent += 2;      for ( int i = 0; i < nodeMap.getLength(); i++ )        display((Entity)nodeMap.item(i));      _indent -= 2;      break;    case Node.ELEMENT_NODE:      System.out.print("ELEM:");      printlnCommon(n);      NamedNodeMap atts = n.getAttributes();      _indent += 2;      for ( int i = 0; i < atts.getLength(); i++ )        display( (Node) atts.item(i) );      _indent -= 2;      break;    case Node.ENTITY_NODE:      System.out.print("ENT:");      printlnCommon(n);      break;    case Node.ENTITY_REFERENCE_NODE:      System.out.print("ENT_REF:");      printlnCommon(n);      break;    case Node.NOTATION_NODE:      System.out.print("NOTATION:");      printlnCommon(n);      break;    case Node.PROCESSING_INSTRUCTION_NODE:      System.out.print("PROC_INST:");      printlnCommon(n);      break;    case Node.TEXT_NODE:      System.out.print("TEXT:");      printlnCommon(n);      break;    default:      System.out.print("UNSUPPORTED NODE: " + type);      printlnCommon(n);      break;    }    // Print children if any    _indent++;    for ( Node child = n.getFirstChild(); child != null;        child = child.getNextSibling() )      display(child);    _indent--;  }  /**   * Main entry point.   *   * @param args The first command line parameter specifies the URL or filename.   */  public static void main(String args[])  {    InputStream f=null;    if ( args.length!=1 ) {      // display usage      System.out.println("Usage:");      System.out.println("javac ParseXML [qif file or URL to parse]");      System.exit(0);    }    try {      // first try and open it as a file      f = new FileInputStream( new File(args[0]) );    } catch ( FileNotFoundException e ) {      // if it fails as a file, try as a URL      try {        HTTPSocket http = new HTTPSocket();        http.send(args[0],null);        f = new StringBufferInputStream(http.getBody());      } catch ( UnknownHostException ee ) {        // if it fails as a URL too, give up        System.out.println("Can't open file or URL named: "                           + args[0] + "(" + ee + ")");        System.exit(0);      } catch ( IOException ee ) {        System.out.println( e );        System.exit(0);      }    }    // parse the XML    try {      DocumentBuilderFactory dbf =      DocumentBuilderFactory.newInstance();      DocumentBuilder db = null;      db = dbf.newDocumentBuilder();      Document doc = null;      doc = db.parse(f);      // Parse the document      display(doc);    } catch ( Exception e ) {      System.out.println("Error: " + e );    }    // close out the file    try {      if ( f!=null )        f.close();    } catch ( IOException e ) {      System.out.println("Error:" + e );      System.exit(0);    }  }}