OSXButtonStyles.scala

import javax.swing._
import java.awt._

val styles = Vector("square", "gradient", "bevel", "textured", "roundRect", "recessed", "help", "segmented", "segmentedRoundRect", "segmentedCapsule", "segmentedTextured", "segmentedGradient")
val p = new JPanel(new FlowLayout())
styles.foreach { style =>
  val b = new JButton()
  if (style != "help") b.setText(style)
  b.putClientProperty("JButton.buttonType", style)
  if (style.startsWith("segmented"))
    b.putClientProperty("JButton.segmentPosition", "only")
  b.setFocusable(false)
  p.add(b)
}
val f = new JFrame()
f.getContentPane.add(p, BorderLayout.CENTER)
f.setResizable(false)
f.pack()
f.setLocationRelativeTo(null)
f.setVisible(true)