TabbedPane problem

package tabbedPaneTest;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.SwingConstants;
import javax.swing.UIManager;

/**
 * TabbedPane
 *
 */
public class TabbedPane extends JTabbedPane { 

	private static TabbedPane instance = null;

	private JPanel bluePanel;
	private JPanel redPanel;
	private JPanel yellowPanel;

	final private int YELLOW_INDEX = 0;
	final private int BLUE_INDEX = 1;
	final private int RED_INDEX = 2;

	private JPanel blueTabTitlePanel;
	private JPanel redTabTitlePanel;
	private JPanel yellowTabTitlePanel;
	
	private JLabel blueLabel;
	private JLabel redLabel; 
	private JLabel yellowLabel;

	
    /**
	 * singleton, call initialize() instead
	 */
	private TabbedPane() {
		setLayout();
	}

	/**
	 * singleton
	 * 
	 * @return
	 */
	public static TabbedPane getInstance()
	{
		if (instance == null) {
			instance = new TabbedPane();
		}
		return instance;
	}

	/** 
	 * set layout of tabs
	 */
	private void setLayout() {

		this.setTabPlacement(SwingConstants.LEFT); // set tabs on left side
		
		FlowLayout flowLayout = new FlowLayout(FlowLayout.LEFT, 5, 5);

		yellowPanel = new JPanel();
		yellowPanel.setName("Yellow");
		this.addTab(yellowPanel.getName(), yellowPanel);
		
		yellowTabTitlePanel = new JPanel();
		yellowTabTitlePanel.setLayout(flowLayout);
		yellowTabTitlePanel.setOpaque(true);
		yellowLabel = new JLabel(yellowPanel.getName());
		yellowLabel.setOpaque(true);
		yellowTabTitlePanel.add(yellowLabel);
		Dimension dimension = yellowTabTitlePanel.getPreferredSize();
		int width = dimension.width;
		int height = dimension.height;
		yellowTabTitlePanel.setPreferredSize(new Dimension(width, height));
		this.setTabComponentAt(YELLOW_INDEX, yellowTabTitlePanel);
		
		bluePanel = new JPanel();
		bluePanel.setName("Blue");
		this.addTab(bluePanel.getName(), bluePanel);
		
		blueTabTitlePanel = new JPanel();
		blueTabTitlePanel.setLayout(flowLayout);
		blueTabTitlePanel.setOpaque(true);
		blueLabel = new JLabel(bluePanel.getName());
		blueLabel.setOpaque(true);
		blueLabel.setBackground(Color.white); // first tab selected
		blueTabTitlePanel.setBackground(Color.white); // first tab selected
		blueTabTitlePanel.add(blueLabel);
		blueTabTitlePanel.setPreferredSize(new Dimension(width, height));
		this.setTabComponentAt(BLUE_INDEX, blueTabTitlePanel);

		redPanel = new JPanel();
		redPanel.setName("Red");
		this.addTab(redPanel.getName(), redPanel);
		
		redTabTitlePanel = new JPanel();
		redTabTitlePanel.setLayout(flowLayout);
		redTabTitlePanel.setOpaque(true);
		redLabel = new JLabel(redPanel.getName());
		redLabel.setOpaque(true);
		redTabTitlePanel.add(redLabel);
		redTabTitlePanel.setPreferredSize(new Dimension(width, height));
		this.setTabComponentAt(RED_INDEX, redTabTitlePanel);
		
	}
	
	/**
	 * 
	 * @param args
	 */
	public static void main(String args[]) {

		try{
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
		}
		catch (Exception e) {
			e.printStackTrace();
		}

		try {

			final JFrame frame = new JFrame();
			TabbedPane tabbedPane =  TabbedPane.getInstance();

			frame.getContentPane().add(new JScrollPane(tabbedPane));
			frame.setTitle("TabbedPane");
			frame.setPreferredSize(new Dimension(500, 500));
			frame.addWindowListener(new WindowAdapter() {
				@Override
				public void windowClosing(WindowEvent e) {
				}
			});

			frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
			frame.setLocation(300, 200);
			frame.pack();
			frame.setVisible(true);

		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}

Select allOpen in new window