Convert tab delimited file content into an xml

Question

Hi,
I am completely new to java and i am trying to create a tree of an
output i have. generally the output is tab delimited and i have a
sample output in the following link
http://jena.sourceforge.net/ontology/examples/class-hierarchy/output.txt
I want to create an xml out of it in the tree format as below
<Class :Thing>
(/t) <Class :KoalaWithPhD>
(/t) <Class :MaleStudentWith3Daughters>
(/t) <Class :Habitat>
</Class :Thing>
note i have added (/t ) just to explain u that kolawithphd is child node of thing ...and so on.
Can someone throw in a simple code snipet that can help me do this.
Really appreciate your help
Thanks
aks

Answer 1

You need to detect the amount of indent, and whether the current line is more or less indented. You also need a stack to hold the indents of the previous lines, so the converter knows which one it's matching.
Assuming the output is like the jena example - spaces only as indent and no non-xml-attribute-value characters in the class names, one possible converter would look like:import java.io.*;
import java.util.*;
public class ClassesToXml {
  public static void main (String[] args) {
    try {
      BufferedReader in = null;
      try {
        in = new BufferedReader(new FileReader(args[0]));
        String line;
        int previousIndent = -1;
        LinkedList stack = new LinkedList();
        System.out.print("<classes");
        while ((line = in.readLine()) != null) {
          final int indent = indent(line);
          if (indent <= previousIndent) {
            System.out.println("/>");
            while (indent < previousIndent) {
              System.out.println("</class>");
              previousIndent = ((Integer)stack.getFirst()).intValue();
              stack.removeFirst();
          } else {
            System.out.println(">");
            stack.addFirst(new Integer(previousIndent));
            previousIndent = indent;
          System.out.print("<class name='" +
                           line.substring(line.indexOf("Class ") + 6).trim() +
        System.out.println("/>");
        while (stack.size() > 1) {
          System.out.println("</class>");
          stack.removeFirst();
        System.out.println("</classes>");
      } finally {
        if (in != null) {
          in.close();
    } catch (IOException ioe) {
      ioe.printStackTrace(System.out);
  static int indent (String line) {
    final int length = line.length();
    for (int indent = 0; indent < length; indent++) {
      if (line.charAt(indent) != ' ') {
        return indent;
    return length;
}Pete