4 different GUI approaches - which is better?

Question

Hi people!
Continuing my Java experiments - now with GUI writing.
I would very much like to know the pros and cons with these 4 different ways to get exactly the same result.
I'm sure some ways are better than others.
class ExperimentGUI
    void ExperimentGUI() // Example A
        JFrame content = new JFrame();
        JTextArea textView = new JTextArea();
        textView.setPreferredSize(new Dimension(300,300));
        content.add(textView, BorderLayout.CENTER);
        content.pack();
        content.setLocationRelativeTo(null);
        content.setVisible(true);
class ExperimentGUI extends JFrame
    void ExperimentGUI() // Example B
        JFrame content = new JFrame();
        JTextArea textView = new JTextArea();
        textView.setPreferredSize(new Dimension(300,300));
        content.add(textView, BorderLayout.CENTER);
        content.pack();
        content.setLocationRelativeTo(null);
        content.setVisible(true);
class ExperimentGUI
    ExperimentGUI() // Example C
        JFrame content = new JFrame();
        JPanel pane = new JPanel(new BorderLayout());
        JTextArea textView = new JTextArea();
        textView.setPreferredSize(new Dimension(300,300));
        pane.add(textView, BorderLayout.CENTER);
        content.setContentPane(pane);
        content.pack();
        content.setLocationRelativeTo(null);
        content.setVisible(true);
class ExperimentGUI extends JFrame
    ExperimentGUI() // Example D
        JPanel content = new JPanel(new BorderLayout());
        JTextArea textView = new JTextArea();
        textView.setPreferredSize(new Dimension(300,300));
        content.add(textView, BorderLayout.CENTER);
        setContentPane(content);
        pack();
        setLocationRelativeTo(null);
        setVisible(true);
}Regards,
Stefan
- a newbie

Answer 1

Be aware that if you declare variable in a local method or constructor, you will have problems with access in other places. Ex:
import java.awt.*;
import java.awt.event.*;
public class ClunkyGui {
//  private  TextArea ta;  // As oposed to global var
//  private  Frame    f;   // As oposed to global var
  public ClunkyGui() {
    Frame    f  = new Frame("ClunkGui");
//    f  = new Frame("ClunkGui");
    TextArea ta = new TextArea(10,20);
//    ta = new TextArea(10,20);
    Button   b  = new Button("GO!");
    b.addActionListener(new BJActionListener());
    Panel    p  = new Panel();
    p.setLayout(new FlowLayout(FlowLayout.CENTER));
    p.add(b);
    f.add(p,BorderLayout.NORTH);
    f.add(ta);
    f.pack();
    f.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent we) {
        f.dispose(); // <access pblm
        System.exit(0);
    f.setVisible(true);
  private class BJActionListener  implements ActionListener {
    public void actionPerformed(ActionEvent ae) {
      ta.setText("HI!"); // <access pblm
  public static void main(String[] argv) {
    new ClunkyGui();
}Now you can code around this and should be able to avoid such things, but just be aware of this.
~Bill