A DOM program that writes Fibonacci numbers onto System.out

import java.math.*;
import java.io.*;
import org.w3c.dom.*;
import org.apache.xerces.dom.*;
import org.apache.xml.serialize.*;


public class FibonacciDOMSerializer {

  public static void main(String[] args) {

    try {

      DOMImplementationImpl impl = (DOMImplementationImpl)
       DOMImplementationImpl.getDOMImplementation();

      DocumentType type = impl.createDocumentType("Fibonacci_Numbers",
       null, null);

      // type is supposed to be able to be null,
      // but in practice that didn't work
      DocumentImpl fibonacci
       = (DocumentImpl) impl.createDocument(null, "Fibonacci_Numbers", type);

      BigInteger low  = BigInteger.ZERO;
      BigInteger high = BigInteger.ONE;

      Element root = fibonacci.createElement("Fibonacci_Numbers");
      // This not only creates the element; it also makes it the
      // root element of the document.

      for (int i = 0; i <= 25; i++) {
        Element number = fibonacci.createElement("fibonacci");
        number.setAttribute("index", Integer.toString(i));
        Text text = fibonacci.createTextNode(low.toString());
        number.appendChild(text);
        root.appendChild(number);
        BigInteger temp = high;
        high = high.add(low);
        low = temp;
      }

      try {
        // Now that the document is created we need to *serialize* it
        OutputFormat format = new OutputFormat(fibonacci);
        XMLSerializer serializer = new XMLSerializer(System.out, format);
        serializer.serialize(root);
      }
      catch (IOException e) {
        System.err.println(e);
      }
    }
    catch (DOMException e) {
      e.printStackTrace();
    }

  }

}