@EventHandler public void onInteract(PlayerInteractEvent event) { if (event.getAction() == Action.LEFT_CLICK_BLOCK || event.getAction() == Action.LEFT_CLICK_AIR) { // (2) final Player player = event.getPlayer(); if (player.getItemInHand().getType() == Material.LEATHER) { Location loc = player.getLocation(); Vector vec = calculateVector(loc); final Creeper creeper = player.getWorld().spawn(loc, Creeper.class); // (3) creeper.setVelocity(vec); creeper.setFireTicks(20); BukkitRunnable runnable = new CowTask(player.getWorld(), creeper); runnable.runTaskTimer(this, 0L, 0L); } } }