JTextField - Show date format mask while inputing

Question

I have searched through the forums and I have not found an instance of someone try to show the format mask while a user inputs chars:
ex: **/**/**** <-- Initialized
1*/**/**** <-- After first integer
10/3*/**** <-- After third integer
I would also like the keep the caret position at the last integer and not always at the end of the input.
Also if a user enters a "t"||"T" that it will automatically enter today's date.
Is there a quick way? I have tried to use a DefaultStyledDocument but have not had success.
Thanks

Answer 1

here's a starter
(needs to handle backspace, delete and probably a few other keys)
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.text.*;
class Testing extends JFrame
  JTextField tf = new JTextField(new MyDoc(),"**/**/**",10);
  public Testing()
    setLocation(400,300);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    JPanel jp = new JPanel();
    jp.add(tf);
    getContentPane().add(jp);
    pack();
  class MyDoc extends PlainDocument
    public void insertString(int offs, String str, AttributeSet a) throws BadLocationException
      if(str.equals("**/**/**") == false && (offs == 2 || offs == 5 ||
         str.length() > 1 || offs > 7 || "0123456789".indexOf(str) < 0))
        java.awt.Toolkit.getDefaultToolkit().beep();
        return;
      StringBuffer newText = new StringBuffer(getText(0,getLength()));
      if(newText.length() > 0)
        newText.setCharAt(offs,str.toCharArray()[0]);
        remove(0,getLength());
        super.insertString(0,newText.toString(),a);
        if(offs == 1 || offs == 4) tf.setCaretPosition(offs+2);
        else tf.setCaretPosition(offs+1);
      else super.insertString(offs,str,a);
  public static void main(String[] args){new Testing().setVisible(true);}
}