/*
 * (C) Copyright IBM Corp. 2004.  All rights reserved.
 *
 * US Government Users Restricted Rights Use, duplication or
 * disclosure restricted by GSA ADP Schedule Contract with IBM Corp.
 *
 * The program is provided "as is" without any warranty express or
 * implied, including the warranty of non-infringement and the implied
 * warranties of merchantibility and fitness for a particular purpose.
 * IBM will not be liable for any damages suffered by you as a result
 * of using the Program. In no event will IBM be liable for any
 * special, indirect or consequential damages or lost profits even if
 * IBM has been advised of the possibility of their occurrence. IBM
 * will not be liable for any third party claims against you.
 */

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.StreamTokenizer;
import java.math.BigInteger;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

public class CsvToSax
  extends DefaultHandler 
{
  static String tagNames[] = {"employeeNumber", 
                              "firstName", 
                              "middleInitial", 
                              "lastName", 
                              "deptNo", 
                              "extension", 
                              "dateOfBirth"};

  public void scanCsvFile(String uri, DefaultHandler dh)
      throws java.io.FileNotFoundException,
             java.io.IOException,
             org.xml.sax.SAXException
  {
    BufferedReader br = new BufferedReader(new FileReader(uri));
    StreamTokenizer st = new StreamTokenizer(br);

    // We want to read the file one line at a time, so end-ofline matters
    st.eolIsSignificant(true);
    // The delimiter between fields is a comma, not a space
    st.whitespaceChars(',', ',');
    // All strings are in double quotes
    st.quoteChar('"');

    char [] lineBreak = new String("\n").toCharArray();
    char [] singleIndent = new String("  ").toCharArray();
    char [] doubleIndent = new String("    ").toCharArray();

    dh.startDocument();
    dh.startElement(null, null, "employees", null);
    dh.ignorableWhitespace(lineBreak, 0, lineBreak.length);

    // Get the first token, then check its type
    st.nextToken();
    while (st.ttype != StreamTokenizer.TT_EOF)
    {
      // We're not at EOF, so start a row
      dh.ignorableWhitespace(singleIndent, 0, singleIndent.length);
      dh.startElement(null, null, "employee", null);
      dh.ignorableWhitespace(lineBreak, 0, lineBreak.length);

      int i = 0;
      while (st.ttype != StreamTokenizer.TT_EOL && 
             st.ttype != StreamTokenizer.TT_EOF)
      {
        // We use the BigInteger class here to write long numbers out
        // Without this, the date fields (which are written something 
        // like (19991013) get converted to scientific notation....
        if (st.ttype == StreamTokenizer.TT_NUMBER)
        {
          char [] chars = BigInteger.valueOf((long)st.nval).
              toString().toCharArray();
          dh.ignorableWhitespace(doubleIndent, 0, doubleIndent.length);
          dh.startElement(null, null, tagNames[i], null);
          dh.characters(chars, 0, chars.length);
          dh.endElement(null, null, tagNames[i]);
          dh.ignorableWhitespace(lineBreak, 0, lineBreak.length);
        }
        else if (st.ttype != StreamTokenizer.TT_EOL &&
                 st.ttype != StreamTokenizer.TT_EOF)
        {
          // For reasons that escape me, if the token is "+", it
          // is interpreted as NULL.
          if (st.sval != null)
          {
            char [] chars = st.sval.trim().toCharArray();
            dh.ignorableWhitespace(doubleIndent, 0, doubleIndent.length);
            dh.startElement(null, null, tagNames[i], null);
            dh.characters(chars, 0, chars.length);
            dh.endElement(null, null, tagNames[i]);
            dh.ignorableWhitespace(lineBreak, 0, lineBreak.length);
          }
        }
        st.nextToken();
        i++;
      }

      // We've hit either the end of the line or the end of the file,
      // so close the row.
      dh.ignorableWhitespace(singleIndent, 0, singleIndent.length);
      dh.endElement(null, null, "employee");
      st.nextToken();
      dh.ignorableWhitespace(lineBreak, 0, lineBreak.length);
    }

    // Now we're at the end of the file, so close the XML document, 
    dh.endElement(null, null, "employees");
    dh.ignorableWhitespace(lineBreak, 0, lineBreak.length);
    dh.endDocument();
  }

  /** Start document. */
  public void startDocument()
  {
    System.out.println("<?xml version=\"1.0\"?>");
  } // startDocument()

  /** Start element. */
  public void startElement(String namespaceURI, String localName, 
                           String rawName, Attributes attrs) 
  {
    System.out.print("<");
    System.out.print(rawName);
    if (attrs != null)
    {
      int len = attrs.getLength();
      for (int i = 0; i < len; i++)
      {
        System.out.print(" ");
        System.out.print(attrs.getQName(i));
        System.out.print("=\"");
        System.out.print(attrs.getValue(i));
        System.out.print("\"");
      }
    }
    System.out.print(">");
  } // startElement(String,AttributeList)

  /** Characters. */
  public void characters(char ch[], int start, int length) 
  {
    System.out.print(new String(ch, start, length));
  } // characters(char[],int,int);

  /** Ignorable whitespace. */
  public void ignorableWhitespace(char ch[], int start, int length) 
  {
    characters(ch, start, length);
  } // ignorableWhitespace(char[],int,int);

  /** End element. */
  public void endElement(String namespaceURI, String localName, 
                         String rawName) 
  {
    System.out.print("</");
    System.out.print(rawName);
    System.out.print(">");
  } // endElement(String)

  /** End document. */
  public void endDocument() 
  {
    // No need to do anything.
  } // endDocument()

  /** Processing instruction. */
  public void processingInstruction(String target, String data) 
  {
    System.out.print("<?");
    System.out.print(target);
    if (data != null && data.length() > 0)
    {
      System.out.print(' ');
      System.out.print(data);
    }
    System.out.print("?>");

  } // processingInstruction(String,String)

  //
  // ErrorHandler methods
  //

  /** Warning. */
  public void warning(SAXParseException ex) 
  {
    System.err.println("[Warning] "+
                       getLocationString(ex)+": "+
                       ex.getMessage());
  }

  /** Error. */
  public void error(SAXParseException ex) 
  {
    System.err.println("[Error] "+
                       getLocationString(ex)+": "+
                       ex.getMessage());
  }

  /** Fatal error. */
  public void fatalError(SAXParseException ex) 
    throws SAXException 
  {
    System.err.println("[Fatal Error] "+
                       getLocationString(ex)+": "+
                       ex.getMessage());
    throw ex;
  }

  /** Returns a string of the location. */
  private String getLocationString(SAXParseException ex) 
  {
    StringBuffer str = new StringBuffer();

    String systemId = ex.getSystemId();
    if (systemId != null)
    {
      int index = systemId.lastIndexOf('/');
      if (index != -1)
        systemId = systemId.substring(index + 1);
      str.append(systemId);
    }
    str.append(':');
    str.append(ex.getLineNumber());
    str.append(':');
    str.append(ex.getColumnNumber());

    return str.toString();
  } // getLocationString(SAXParseException):String

  /** Main program entry point. */
  public static void main(String argv[]) 
  {
    if (argv.length == 0 ||
        (argv.length == 1 && argv[0].equals("-help")))
    {
      System.out.println("\nUsage:  java CsvToSax uri");
      System.out.println("   where uri is the URI of your ");
      System.out.println("     comma-separated values document.");
      System.out.println("   Sample:  java CsvToSax sonnet.xml");
      System.out.println("\nEchoes SAX events back to the console.");
      System.exit(1);
    }

    CsvToSax c2s = new CsvToSax();
    try
    {
      c2s.scanCsvFile(argv[0], c2s);
    }
    catch (FileNotFoundException fnfe) 
    { 
      System.err.println("Error - File " + argv[0] + " not found!"); 
    }
    catch (SAXException se) 
    { 
      System.err.println("SAX Exception: " + se);
    }
    catch (IOException ioe) 
    { 
      System.err.println("IO Exception: " + ioe);
    }
  } // main(String[])
}