Getting blocks in a radius

For my plugin, I would like to check for mob spawners in a radius, so people cannot farm mob spawners for insane amounts of plugin xp.

Code:

            int startx, starty, startz;
            int endx, endy, endz;
            for (int x = startx; x < endx; x++) {
                for (int y = starty; y < endy; y++) {
                    for (int z = startz; z < endz; z++) {
                        Block block = world.getBlockAt(x, y, z);
                        if (block.getTypeId() == 52)
                            return;
                    }
                }
            }

It's throwing an error at "world.getBlockAt()" (world cannot be resolved)

Any suggestions? :3

 

If you have a player use player.getWorld, if you have an event use event.get(Entity, Player, Block)().getWorld().
If you have none of those you can use getServer().getWorlds().get(0)

 

You haven't defined "world"

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