public void loopThrough(Location loc1, Location loc2, World w) {
    int minx = Math.min(loc1.getBlockX(), loc2.getBlockX()),
    miny = Math.min(loc1.getBlockY(), loc2.getBlockY()),
    minz = Math.min(loc1.getBlockZ(), loc2.getBlockZ()),
    maxx = Math.max(loc1.getBlockX(), loc2.getBlockX()),
    maxy = Math.max(loc1.getBlockY(), loc2.getBlockY()),
    maxz = Math.max(loc1.getBlockZ(), loc2.getBlockZ());
    for (int x = minx; x<=maxx;x++) {
        for (int y = miny; y<=maxy;y++) {
            for (int z = minz; z<=maxz;z++) {
                Block b = w.getBlockAt(x, y, z);
                //do somthing productive with b...
            }
        }
    }
}