Differentiating between 21st 20th century years

Question

I am wirting an applicaion for a mysql database where in I have to populate some very old data in to the database.For that I need to convert dates from the format "MM/dd/yy" into the format "yyyy-mm-dd"( this format being used in mysql).Although I have written the following code to do the conversion, I still have a problem.HOw do I make it recognize centuries i.e 1906 or 2006?
public class Datedemo extends Object {
String convertDate(String oldate){
     String strdate=null;
     try{     
     SimpleDateFormat sdfOutput = new SimpleDateFormat ( "yyyy-MM-dd" );
     DateFormat df=DateFormat.getDateInstance(DateFormat.SHORT,Locale.US);
     Date myDate =df.parse(oldate);
     strdate=sdfOutput.format(myDate);
     }catch (ParseException ae){}
     return strdate;
     public static void main(String args[])
          String newdate;
          Datedemo datedemo=new Datedemo ();
     newdate=datedemo.convertDate("03/23/06");
     System.out.print (newdate);
How does java recognize whether a year is in this century or in the last e.g how do I a make a date like 03/23/06 (06 meaning 1906) to 1906-03-23.Java converts it to 2006-03-23.Although for some dates like 03/23/31 java corectly converts it to 1931-03-23 it doesnt do that for some earlier years.
How do I get around this?Thanks in advance for any help regarding this.
RS

Answer 1

See this API link on the SimpleDateFormat class:
http://java.sun.com/j2se/1.3/docs/api/java/text/SimpleDateFormat.html
Read the Code Sample: section, 2nd paragraph on how this class handles 2 digit years