Need help with error BlockState cannot be cast to Sign

Hi everyone,
Everytime , when I worked with Sign lines, something like this code worked:

Code:

Sign s;
BlockState st =b.getState();
            if(st instanceof Sign){
                  s = (Sign)st;
            }
s.setLine(0, "Red: " + reds.size());
            s.setLine(1, "Blue: " + blues.size());
            s.update();

(b is a block and reds and blues are ArrayLists)
But now, I am getting an error:

Whats wrong with my code?
Thankx

 

Have you imported the wrong Sign?

 

nisovin
I have imported import org.bukkit.block.Sign; because with Material, Im getting error om setLine()

 

could try something like this.

Code:Java

if (b != null) {
    BlockState st =b.getState();
    if (st instanceof Sign) {
        Sign s = (Sign) st;
        s.setLine(0, "herp");
        s.update();
    }
}

EDIT: Updated the code.. had an error.

 

I don't understand how, and I dont understand why, but it started to work, when I adden Muddr 's statement.
Thank you really much