Error while running this small Application. Please Guide

Question

Hello Folks
I am getting this error when I run this small application.
Can some one please tell me what is the problem?
Attached is the ERROR and the CLASS.
The ERROR is:
java.lang.NullPointerException
     at javax.swing.plaf.basic.BasicTabbedPaneUI$TabbedPaneLayout.calculateSize(BasicTabbedPaneUI.java:1293)
     at javax.swing.plaf.basic.BasicTabbedPaneUI$TabbedPaneLayout.preferredLayoutSize(BasicTabbedPaneUI.java:1272)
     at java.awt.Container.preferredSize(Container.java:836)
     at java.awt.Container.getPreferredSize(Container.java:820)
     at javax.swing.JComponent.getPreferredSize(JComponent.java:1044)
CLASS:
public class BlankPaneDemo {
private JTabbedPane tabbedPane;
private JFrame dlframe;
// Constructor.
public BlankPaneDemo() {
dlframe = new JFrame("The Plumes Proxy ");
tabbedPane = new JTabbedPane(SwingConstants.LEFT);
tabbedPane.setBackground(Color.blue);
tabbedPane.setForeground(Color.white);
// Calls a method that adds individual tabs to the
// tabbedpane object.
populateTabbedPane();
dlframe.getContentPane().add(tabbedPane);
dlframe.pack();
dlframe.setSize(765, 690);
dlframe.setBackground(Color.white);
dlframe.setVisible(true);
} // End Constructor.
private void populateTabbedPane()
tabbedPane.addTab("Welcome",
null,
null,
"Welcome Options");
public static void main(String[] args)
BlankPaneDemo bpd = new BlankPaneDemo();
} // End Class.

Answer 1

Which version of jdk are you using ?
in jdk1.4 it is working fine on my system,
May be there is problem with passing null component in statement :
tabbedPane.addTab("Welcome", null, null, "Welcome Options");