Java: BoxAlignmentDemo

/*
 * BoxAlignmentDemo.java requires the following files:
 *   public/images/article/middle.gif
 *   public/images/article/geek-cght.gif
 *
 * This demo shows how to specify alignments when you're using
 * a BoxLayout for components with maximum sizes and different
 * default alignments.
 */

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

public class BoxAlignmentDemo extends JPanel {
    public BoxAlignmentDemo() {
        super(new BorderLayout());
        JTabbedPane tabbedPane = new JTabbedPane();

        JPanel buttonRow = new JPanel();
        //Use default FlowLayout.
        buttonRow.add(createButtonRow(false));
        buttonRow.add(createButtonRow(true));
        tabbedPane.addTab("Altering alignments", buttonRow);

        JPanel labelAndComponent = new JPanel();
        //Use default FlowLayout.
        labelAndComponent.add(createLabelAndComponent(false));
        labelAndComponent.add(createLabelAndComponent(true));
        tabbedPane.addTab("X alignment mismatch", labelAndComponent);

        JPanel buttonAndComponent = new JPanel();
        //Use default FlowLayout.
        buttonAndComponent.add(createYAlignmentExample(false));
        buttonAndComponent.add(createYAlignmentExample(true));
        tabbedPane.addTab("Y alignment mismatch", buttonAndComponent);

        //Add tabbedPane to this panel.
        add(tabbedPane, BorderLayout.CENTER);
    }

    protected JPanel createButtonRow(boolean changeAlignment) {
        JButton button1 = new JButton("A JButton",
                                      createImageIcon("public/images/article/middle.gif"));
        button1.setVerticalTextPosition(AbstractButton.BOTTOM);
        button1.setHorizontalTextPosition(AbstractButton.CENTER);

        JButton button2 = new JButton("Another JButton",
                                      createImageIcon("public/images/article/geek-cght.gif"));
        button2.setVerticalTextPosition(AbstractButton.BOTTOM);
        button2.setHorizontalTextPosition(AbstractButton.CENTER);

        String title;
        if (changeAlignment) {
            title = "Desired";
            button1.setAlignmentY(BOTTOM_ALIGNMENT);
            button2.setAlignmentY(BOTTOM_ALIGNMENT);
        } else {
            title = "Default";
        }

        JPanel pane = new JPanel();
        pane.setBorder(BorderFactory.createTitledBorder(title));
        pane.setLayout(new BoxLayout(pane, BoxLayout.X_AXIS));
        pane.add(button1);
        pane.add(button2);
        return pane;
    }

    protected JPanel createLabelAndComponent(boolean doItRight) {
        JPanel pane = new JPanel();

        JComponent component = new JPanel();
        Dimension size = new Dimension(150,100);
        component.setMaximumSize(size);
        component.setPreferredSize(size);
        component.setMinimumSize(size);
        TitledBorder border = new TitledBorder(
                                  new LineBorder(Color.black),
                                  "A JPanel",
                                  TitledBorder.CENTER,
                                  TitledBorder.BELOW_TOP);
        border.setTitleColor(Color.black);
        component.setBorder(border);

        JLabel label = new JLabel("This is a JLabel");
        String title;
        if (doItRight) {
            title = "Matched";
            label.setAlignmentX(CENTER_ALIGNMENT);
        } else {
            title = "Mismatched";
        }

        pane.setBorder(BorderFactory.createTitledBorder(title));
        pane.setLayout(new BoxLayout(pane, BoxLayout.Y_AXIS));
        pane.add(label);
        pane.add(component);
        return pane;
    }

    protected JPanel createYAlignmentExample(boolean doItRight) {
        JPanel pane = new JPanel();
        String title;

        JComponent component1 = new JPanel();
        Dimension size = new Dimension(100, 50);
        component1.setMaximumSize(size);
        component1.setPreferredSize(size);
        component1.setMinimumSize(size);
        TitledBorder border = new TitledBorder(
                                  new LineBorder(Color.black),
                                  "A JPanel",
                                  TitledBorder.CENTER,
                                  TitledBorder.BELOW_TOP);
        border.setTitleColor(Color.black);
        component1.setBorder(border);

        JComponent component2 = new JPanel();
        size = new Dimension(100, 50);
        component2.setMaximumSize(size);
        component2.setPreferredSize(size);
        component2.setMinimumSize(size);
        border = new TitledBorder(new LineBorder(Color.black),
                                  "A JPanel",
                                  TitledBorder.CENTER,
                                  TitledBorder.BELOW_TOP);
        border.setTitleColor(Color.black);
        component2.setBorder(border);

        if (doItRight) {
            title = "Matched";
        } else {
            component1.setAlignmentY(TOP_ALIGNMENT);
            title = "Mismatched";
        }

        pane.setBorder(BorderFactory.createTitledBorder(title));
        pane.setLayout(new BoxLayout(pane, BoxLayout.X_AXIS));
        pane.add(component1);
        pane.add(component2);
        return pane;
    }

    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path) {
        java.net.URL imgURL = BoxAlignmentDemo.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }

    /**
     * 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("BoxAlignmentDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        BoxAlignmentDemo newContentPane = new BoxAlignmentDemo();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        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(() -> {
            createAndShowGUI();
        });
    }
}