private void verifyTileAt(CrystalNetworkTile te, WorldLocation loc) { UUID key = te.getUniqueID(); WorldLocation prev = verifier.get(key); if (prev != null && !prev.equals(loc)) { te.getWorld().setBlockToAir(te.getX(), te.getY(), te.getZ()); throw new InvalidLocationException(te, loc, prev); } else verifier.put(key, loc); }