Steps to reproduce:
1. Compile and run the attached testcase

Expected results:
1. A window with two labels and a textfield between the labels shows up.

Actual results:
1. A window with two labels shows up but the textfield is not visible.

Testcase:

import javax.swing.*;
import java.awt.*;
public class jtextfield extends JFrame {
        public static void main(String[] args) {
                (new jtextfield()).show();
        }
        public jtextfield() {
                JPanel panel = new JPanel();
                panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
                panel.add(new JLabel("label1"));
                panel.add(new JTextField(4));
                panel.add(new JLabel("label2"));
                this.setContentPane(panel);
                this.pack();
        }
}

If I comment out the line that does setLayout the textfield is visible.