HSPLet自体に手を入れれば次のような感じで実装できます。
mouse命令の機能のうちマウスカーソルの移動は特権が必要なのでjarに署名しないと動きません。
hsplet.function.GuiCommand.mouse(Context, Operand, int, Operand, int)
public static void mouse(final Context context, final Operand x1v, final int x1vi, final Operand y1v, final int y1vi) {
final Bmscr win = (Bmscr) context.windows.get(context.targetWindow);
if (hideCursor == null) {
int size = 1;
int[] pixels = new int[size * size];
Image image = Toolkit.getDefaultToolkit().createImage(new MemoryImageSource(size, size, pixels, 0, size));
hideCursor = Toolkit.getDefaultToolkit().createCustomCursor(image, new Point(0, 0), "hide");
}
final int x1 = toInt(x1v, x1vi, context.mouseX);
final int y1 = toInt(y1v, y1vi, context.mouseY);
if (x1 < 0 || y1 < 0) {
if (win != null && win.component != null) {
win.component.setCursor(hideCursor);
}
return;
}
if (win != null && win.component != null) {
win.component.setCursor(Cursor.getDefaultCursor());
}
try {
Robot r = new Robot();
r.mouseMove(x1, y1);
} catch (AWTException ae) {
ae.printStackTrace();
} catch (SecurityException se) {
se.printStackTrace();
}
}