public class Fenster extends JFrame {
public Fenster(){
Container c = this.getContentPane();
JTabbedPane tpane = new JTabbedPane();
tpane.addTab("Tab1", new JPanel());
tpane.addTab("Tab2", new JPanel());
tpane.setBounds(0, 0, 200, 200);
this.setLayout(null);
this.add(tpane);
this.setSize(500, 500);
this.setVisible(true);
}
}