Naviguer entre les onglets en java

package fonctions;

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.JTextArea;

public class BenBanana extends JFrame {
	private static final long serialVersionUID = 1L;

	class MyJTextPane extends JPanel {
		private static final long serialVersionUID = 1L;
		JTextArea ta;

		public MyJTextPane() {
			setLayout(new BorderLayout());
			ta = new JTextArea();
			add(ta, BorderLayout.CENTER);
		}

		public JTextArea getTextArea() {
			return ta;
		}
	}

	public static void main(String[] args) {
		final BenBanana mf = new BenBanana();
		mf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		mf.setBounds(20, 20, 500, 500);

		mf.setLayout(new BorderLayout());
		final JTabbedPane tabbedPane = new JTabbedPane();
		JPanel p1 = mf.new MyJTextPane();
		JPanel p2 = mf.new MyJTextPane();
		tabbedPane.add("First pane", p1);
		tabbedPane.add("Second one", p2);
		mf.add(tabbedPane, BorderLayout.CENTER);

		JPanel southPane = new JPanel();
		JButton infoBtn = new JButton("Get info");
		infoBtn.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				// afficher le contenu du JTextArea actif (1 ou 2)
				BenBanana.MyJTextPane selectedTab = ((BenBanana.MyJTextPane) tabbedPane
						.getSelectedComponent());
				JOptionPane.showMessageDialog(mf, "Current active JTA reads:\n"
						+ selectedTab.getTextArea().getText());
			}
		});
		southPane.add(infoBtn);
		mf.add(southPane, BorderLayout.SOUTH);

		mf.setVisible(true);
	}
}

// Déclaration de ma table d'onglets
private JTabbedPane onglets = new JTabbedPane(); 

// Nouveau correspond à un JMenuItem
nouveau.addActionListener(new ActionListener() {
			
			public void actionPerformed(ActionEvent e) {

				onglets.add("Onglet", new JTextArea());
				
			}
});

class actionOuvrir implements ActionListener
	{

		public void actionPerformed(ActionEvent e) {
			
			JFileChooser fileChoose = new JFileChooser();
			fileChoose.setCurrentDirectory(new File("~"));;
			String fichier = null;
			
			int resultatOuvrir = fileChoose.showDialog(fileChoose, new String("Ouvrir"));
			
			if (resultatOuvrir == JFileChooser.APPROVE_OPTION) {
				
				fichier = fileChoose.getSelectedFile().toString();
				
				FileInputStream fis;
				try {
					
					fis = new FileInputStream(fichier);
					 int n;
					   
					   while ((n = fis.available())> 0) {
						   
						   byte[] b = new byte[n];
						   int result = fis.read(b);
					      if (result == -1) break;
					      String s = new String(b);
                                             // Ici la ligne manquante pour  insérer la chaine s dans mon onglet
					      
					   }
					   
				} catch (FileNotFoundException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				} catch (IOException e2) {
					// TODO Auto-generated catch block
					e2.printStackTrace();
				}
			}
		}
	}