Trouble updating signs

I'm having trouble updating signs. It works 99% of the time, but sometimes the sign isn't updated. In the following code, line1, etc, are the lines on the sign, and arg[1], etc, are the sign's location. I dump out line and arg, and they're all correct. The calls to block.getType work, so it must be finding the sign correctly. The call to sign.update returns true. I can check the sign with another client, so it's not a client issue.

So am I doing something wrong? Is this the correct way to update a sign? Is block.getState what I should be using?

Code:

Location loc = new Location(plugin.getServer().getWorld(arg[1]),
                            Double.valueOf(arg[2]),
                            Double.valueOf(arg[3]),
                            Double.valueOf(arg[4]));
 
World world = loc.getWorld();
Block block = world.getBlockAt(loc);
 
if(block.getType() == Material.SIGN_POST ||
   block.getType() == Material.WALL_SIGN)
{
    Sign sign = (Sign)block.getState();
    sign.setLine(0, line1);
    sign.setLine(1, line2);
    sign.setLine(2, line3);
    sign.setLine(3, line4);
    sign.update();
}

 

Should be working correctly, did you really double-checked all Parameters?

 

Johnny Crazy Yup I checked everything I mentioned, by dumping to the chat window and or the console:

• sign lines (line...)
• sign location (arg[])
• the if statement works (is true)
• sign.update returns true

all correct even when the sign doesn't get updated.

I'll keep looking at it in case I missed something. If anyone else has suggestions, let me know.

It looks like it may be related to chunk loading/unloading. If I park a second player near the sign so the chunk stays loaded, the problem doesn't occur.

This doesn't make a lot of sense to me, because the check for the block material is working. If the chunk wasn't loaded, how could that pass?

In any case, how would I modify the above code to ensure the chunk is loaded? I'm not sure what methods to call.

EDIT: Added calls to loc.getChunk and chunk.load, but it didn't help.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.