Bukkit

        @EventHandler	
    	public void Granaten(PlayerInteractEvent e){ 
    	if(e.getAction() == Action.RIGHT_CLICK_AIR){ 
    	Player p = e.getPlayer();
	    	ItemStack Granate = new ItemStack(Material.DIAMOND, 1);
            ItemMeta meta52 = Granate.getItemMeta();
            Granate.setItemMeta(meta52);
    	
    	if(p.getItemInHand().getType() == Material.DIAMOND){			 
    	final Item Grenade = p.getWorld().dropItem(p.getEyeLocation(), Granate);	
    	Grenade.setVelocity(p.getEyeLocation().getDirection().multiply(1.8));
    	

      	 if(p.getInventory().contains(Material.DIAMOND)){

        	 p.getInventory().removeItem(Granate);
        	 p.updateInventory(); 
        	 }
        	Bukkit.getScheduler().scheduleSyncDelayedTask(this, new Runnable() {
        		public void run() {
        			
	               	if(Grenade.isOnGround()){
	               		Grenade.remove();
	               		World world = Grenade.getWorld();
	               		
	               		world.createExplosion(Grenade.getLocation(), 4);
	                     
	               		
	                     world.playEffect(Grenade.getLocation(), Effect.WITCH_MAGIC, 9);
	                     world.playEffect(Grenade.getLocation(), Effect.LAVA_POP, 9);
	                     
	             }
          }
        }, 80L);
         }
    	}
    	}