Java tutorial
import java.awt.BorderLayout; import java.awt.Color; import java.awt.Component; import java.awt.Container; import java.awt.Graphics; import java.awt.Insets; import javax.swing.AbstractButton; import javax.swing.ButtonModel; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.border.AbstractBorder; import javax.swing.border.Border; public class RedGreenBorder extends AbstractBorder { public boolean isBorderOpaque() { return true; } public Insets getBorderInsets(Component c) { return new Insets(3, 3, 3, 3); } public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) { Insets insets = getBorderInsets(c); Color horizontalColor; if (c.isEnabled()) { boolean pressed = false; if (c instanceof AbstractButton) { ButtonModel model = ((AbstractButton) c).getModel(); pressed = model.isPressed(); } if (pressed) { horizontalColor = Color.RED; } else { horizontalColor = Color.GREEN; } } else { horizontalColor = Color.LIGHT_GRAY; } g.setColor(horizontalColor); g.fillRect(0, 0, width, insets.top); } public static void main(String args[]) { JFrame frame = new JFrame("My Border"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); Border border = new RedGreenBorder(); JButton helloButton = new JButton("Hello"); helloButton.setBorder(border); JButton braveButton = new JButton("Brave New"); braveButton.setBorder(border); braveButton.setEnabled(false); JButton worldButton = new JButton("World"); worldButton.setBorder(border); Container contentPane = frame.getContentPane(); contentPane.add(helloButton, BorderLayout.NORTH); contentPane.add(braveButton, BorderLayout.CENTER); contentPane.add(worldButton, BorderLayout.SOUTH); frame.setSize(300, 100); frame.setVisible(true); } }