Create Block HELP please!

Hi, Ive just put together two pieces of code
One from user yottabyte
One From Tent plugin.
There it is:

Code:

    public void onPlayerInteract(PlayerInteractEvent event){
        Player player = event.getPlayer();
        if(event.getAction() == Action.RIGHT_CLICK_BLOCK){
            Block b = event.getClickedBlock();
            if(b.getType() == Material.SIGN_POST){
                  if(((Sign)b.getState()).getLines()[0].equals("[BARAK]")){
                      for(int q = 1;q <= 3; q++){
                            Block newBlock = player.getWorld().getBlockAt(b.getX(), b.getY()+q, b.getZ());
                            newBlock.setTypeId(49);
 
    }
            }
        }
    }

It should(I think) create 3 block of obsidian onclick on the Sign, but if i do this, There is just simple message appeared in chat: diff.
Can you help little , san noob that want to make at least one plugin?
Thanks

 

You're missing one } at the end but it will work.

 

Ive added one, but still.. there is just an message diff in the chat window.. but nothing more

 

That's nothing to do with this code though. The code above (once you add that } ) does exactly what it should do. No idea where that message is coming from, either somewhere else in your code or another plugin.