pocketmine\item\Item::isAxe PHP Method

    public function isAxe()
    {
        return false;
    }

 public function getBreakTime(Item $item)
 {
     switch ($item->isAxe()) {
         case 5:
             return 0.4;
         case 4:
             return 0.5;
         case 3:
             return 0.75;
         case 2:
             return 0.25;
         case 1:
             return 1.5;
         default:
             return 3;
     }
 }