String line;                                        // 1
while ( (line = bufferedReader.readLine()) != null) // 2
{                                                   // 3
  Vector aLine = new Vector();                      // 4
  aLine.add(stringToVector(line));                  // 5
  System.out.println("what is aLine " +aLine );     // 6
  data.addAll(aLine);                               // 7
}                                                   // 8

public class MyCustomVector 
  extends java.util.Vector
{
 
  
...
 
 
public String toString()
{
  synchronize(this)
  {
    Object[] o = this.toArray(); 
    // Check if this is fast enough or may be you could try to access the 
   // protected  Object[] elementData of the java.util.Vector
  } // End of synchronization
  StringBuffer buf = new StringBuffer();
 
  // This is not excatly what you want but 
  // removing the last comma should not be an issue
  //
  for (int i = 0; i < o.length; i++)
    buf.append(o[i]).append(',');
  // Please not that the forum has a problem.
  // It dislays comparison (greater/smaller) signs around the "i" 
  // They are in fact square brackets, instead !!!
  return buf.toString();
}

public static Vector stringToVector(String string)
{
  // can't you give a char ',' instead of a String ","
  StringTokenizer tokenizer = new StringTokenizer(string, ",", false);
  Vector row = new Vector();
  while(tokenizer.hasMoreTokens())
  {
    String valueOfToken = tokenizer.nextToken();
    // trimming the String before adding it ?
    row.addElement(valueOfToken.trim());
  }
  return row;
}