Graphics repaint() NOT Firing

Consider the code below for a graphics class that will be used for painting a time-series chart. For now it just prints "painting"

public class ChartingPanel extends JPanel {

public void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("painting");

}

}

This function is used elsewhere in my program. It has a static call and is on a thread.

public void historicalData(int reqId, String date, double open, double high, double low,
double close, int volume, int count, double WAP, boolean hasGaps) {

System.out.println(date + " " + open + " " + high + " " + low + " " + close);

chartingPanel.repaint();

}

What I want to happen is to generate a printout like this:

20120614 06:00:00 1.25565 1.2586 1.2553 1.25705
painting
20120614 07:00:00 1.25705 1.25785 1.25555 1.2567
painting
20120614 08:00:00 1.2567 1.2589 1.2551 1.2579
painting
20120614 09:00:00 1.2579 1.2601 1.25635 1.25995
painting

What's happening is a printout like this:

painting
painting
20120607 17:15:00 1.2561 1.2565 1.25605 1.2564
20120607 18:00:00 1.2564 1.25715 1.2563 1.25685
painting
20120607 19:00:00 1.25685 1.2575 1.25665 1.2568
20120607 20:00:00 1.2568 1.2572 1.25295 1.254
painting
20120607 21:00:00 1.254 1.25425 1.25225 1.25245
20120607 22:00:00 1.25245 1.2529 1.25145 1.2528
painting
20120607 21:00:00 1.254 1.25425 1.25225 1.25245
20120607 22:00:00 1.25245 1.2529 1.25145 1.2528
20120607 23:00:00 1.2528 1.2533 1.25215 1.25215
20120608 00:00:00 1.25215 1.2529 1.2518 1.25245

---------------------------------------------------------------------------------

Some sort of synchronization issue with the Graphics. The repaint() method is not firing for every time the historicalData is called. What can I do to fix this ????