//BoxLayoutFrame.javaimport java.awt.*;import javax.swing.*;public class BoxLayoutFrame extends JFrame {  BoxLayoutTest panel = new BoxLayoutTest();  public BoxLayoutFrame() {    this.getContentPane().add(panel);    this.setSize(500,220);    this.setTitle("BoxLayoutDemo");    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    this.show();  }  public static void main(String[] args) {    BoxLayoutFrame frame = new BoxLayoutFrame();  }}class BoxLayoutTest extends JPanel {  BoxLayoutTest() {    // Set the layout to a y-axis BoxLayout    setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));    // Create three components    TextField textField = new TextField();    TextArea textArea = new TextArea(4, 20);    JButton button = new JButton(      "Click me!");    // Add the three components to the BoxLayout    add(new JLabel("TextField"));    add(textField);    add(new JLabel("TextArea"));    add(textArea);    add(new JLabel("Button"));    add(button);  }}