Java window component bug

Given the below java code:

import java.awt.*;
import javax.swing.*;

public class WindowSwing {
    /**
     * Create the GUI and show it.  For thread safety,
     * this method should be invoked from the
     * event-dispatching thread.
     */
    private static void createAndShowGUI() {
        //Create and set up the window.
        JFrame frame = new JFrame("Windows Asgn");
        frame.setSize(400, 150);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create container
        Container content = frame.getContentPane();

        //Add JButton
        JButton button = new JButton("JButton");
        content.add(button);

        //Add JLabel.
        JLabel label = new JLabel("Enter Your First Name Below:");
        content.add(label);

        //Add JtextField
        JTextField textFld = new JTextField();
        content.add(textFld);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
        //frame.addWindowListener(new ExitListener());
          //frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

The window run is very small. None of the components show. Why? Please advise.
Thanks.