Cannot cast CraftBlockState to Sign

I'm having this strange error while casting from BlockState to Sign, I say strange since I have done this many times now, what could be causing it?

The error is on line 4 on the following:

Code:java

Sign s = null;
final Location l = b.getLocation();
if (l.add(1, 0, 0).getBlock().getType()==Material.WALL_SIGN){
    s = (Sign) l.add(1, 0, 0).getBlock().getState();
}

b is referring to "Block b" which in the moment of the error was a block of Stone (I know it doesn't matter, just to say its not null)

 

Simple. Your location l, in the evaluation part of the if-statement you are adding 1, 0, 0 to it. And checking if the block at its position is a sign. Then, when you cast, you take the already modified location and add 1, 0, 0 to it yet again, The location is now no longer at the sign location. See now?

 

Hmmm I thought that by making the Location final it wouldn't be affected by the add, thanks.

 

Declaring the variable final only means you cannot change the reference. The object will still be mutable.