import javax.swing.*;
import javax.swing.border.AbstractBorder;
import javax.swing.border.Border;
import javax.swing.border.CompoundBorder;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

/**
 * "Crazy JButton painters" from 
 *  http://weblogs.java.net/blog/alexfromsun/
 * 
 * Note: please consider this code as a joke,
 * I don't recommend using all this dirty tricks 
 *  
 * @author Alexander Potochkin
 */
public class ButtonPainter extends JFrame {

    private JButton button;

    public ButtonPainter() {
        setTitle("Crazy JButton painters");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);

        JPanel buttonPanel = new JPanel(new GridBagLayout());
        button = new JButton("Hello World !", new TestIcon());
        button.setPreferredSize(new Dimension(150, 70));
        buttonPanel.add(button);

        buttonPanel.setBorder(BorderFactory.createEtchedBorder());
        add(buttonPanel);
        add(createOptionsPanel(), BorderLayout.WEST);

        setSize(400, 200);
        setLocationRelativeTo(null);
    }

    private JComponent createOptionsPanel() {
        Box panel = new Box(BoxLayout.Y_AXIS);
        panel.add(Box.createVerticalGlue());
        final JCheckBox componentButton = new JCheckBox("Component");
        componentButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                button.removeAll();
                if (componentButton.isSelected()) {
                    button.setLayout(new BorderLayout());
                    button.add(new ComponentPainter());
                }
                button.revalidate();
                button.repaint();
            }
        });
        panel.add(componentButton);
        panel.add(Box.createVerticalGlue());
        final JCheckBox borderButton = new JCheckBox("Border");
        borderButton.addActionListener(new ActionListener() {
            private Border oldBorder = button.getBorder();

            public void actionPerformed(ActionEvent e) {
                if (borderButton.isSelected()) {
                    button.setBorder(new CompoundBorder(oldBorder, new BorderPainter()));
                } else {
                    button.setBorder(oldBorder);
                }
            }
        });
        panel.add(borderButton);
        panel.add(Box.createVerticalGlue());
        final JCheckBox iconButton = new JCheckBox("Icon");
        iconButton.addActionListener(new ActionListener() {
            private Icon oldIcon = button.getIcon();

            public void actionPerformed(ActionEvent e) {
                if (iconButton.isSelected()) {
                    button.setIcon(new IconPainter(oldIcon));
                } else {
                    button.setIcon(oldIcon);
                }
            }
        });
        panel.add(iconButton);
        panel.add(Box.createVerticalGlue());
        panel.setBorder(BorderFactory.createEtchedBorder());
        return panel;
    }

    class ComponentPainter extends JPanel {
        protected void paintComponent(Graphics g) {
            Graphics2D g2 = (Graphics2D) g.create();
            // It enables painting outside the component's border
            g2.setClip(null);
            // Make it translucent
            g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.3f));
            // Take button's insets into account
            Insets insets = button.getInsets();
            // Custom painting
            g2.setColor(Color.ORANGE);
            g2.fillOval(-insets.left, -insets.top, button.getWidth(), button.getHeight());
            g2.setColor(Color.GRAY);
            g2.drawOval(-insets.left, -insets.top, button.getWidth(), button.getHeight());
            g2.dispose();
        }
    }

class BorderPainter extends AbstractBorder {
    public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
        Graphics2D g2 = (Graphics2D) g.create();
        g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.3f));
        g2.setPaint(new GradientPaint(0, 10, Color.BLACK, 10, 10, Color.RED, true));
        // We are free to paint wherever we want :-)
        g2.fillRect(0, 0, button.getWidth(), button.getHeight());
    }
}

class IconPainter implements Icon {
    private final Icon delegateeIcon;

    public IconPainter(Icon innerIcon) {
        this.delegateeIcon = innerIcon;
    }

    public int getIconWidth() {
        if (delegateeIcon != null) {
            return delegateeIcon.getIconWidth();
        }
        return 0;
    }

    public int getIconHeight() {
        if (delegateeIcon != null) {
            return delegateeIcon.getIconHeight();
        }
        return 0;
    }

    public void paintIcon(Component c, Graphics g, int x, int y) {
        if (delegateeIcon != null) {
            delegateeIcon.paintIcon(c, g, x, y);
        }
        Graphics2D g2 = (Graphics2D) g.create();
        g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.3f));
        g2.setPaint(new GradientPaint(10, 0, Color.RED, 10, 10, Color.BLUE, true));
        // It is special icon, it is not interesed in x, y and icon's size 
        g2.fillRect(0, 0, button.getWidth(), button.getHeight());
    }
}


    public static void main(String[] args) throws Exception {
        new ButtonPainter().setVisible(true);
    }
}

class TestIcon implements Icon {
    public int getIconHeight() {
        return 20;
    }

    public int getIconWidth() {
        return 20;
    }

    public void paintIcon(Component c, Graphics g, int x, int y) {
        g.setColor(Color.GREEN.darker());
        g.fillOval(x, y, getIconWidth(), getIconHeight());
    }
}