$15\mathrm{.}3($Move the ball$)$ Write a program that moves the ball in a pane. You should define a pane class for displaying the ball and provide the methods for moving the ball left, right, up$,$ and down, as shown in Figure $15\mathrm{.}26$c$.$ Check the boundary to prevent the ball from moving out of sight completely.

$($c$)$

FiGure $15\mathrm{.}26($c$)$ Exercise $15\mathrm{.}3$ uses the buttons to move the ball.