Block Radius Excerpt

int radius = BlocksRadius.get(key);
Location location = event.getEntity().getLocation();
World world = location.getWorld();
HashSet<Block> blocklist = new HashSet<Block>();
for (int x = -(radius); x <= radius; x ++) {
    for (int y = -(radius); y <= radius; y ++) {
        for (int z = -(radius); z <= radius; z ++) {
            Block b = location.getWorld().getBlockAt(x + location.getBlockX(), y + location.getBlockY(), z + location.getBlockZ());
            blocklist.add(b);
        }
    }
}
for(Block b: blocklist) {
    Integer[] pairs = BlockPairs.get(key);
    if(b.getTypeId() == pairs[0]) {
        world.getBlockAt(b.getLocation()).setTypeId(pairs[1]);
    }
}