Get block relative to players location and direction.

I've tried several ways and non have worked. I googled the forums and I fount some that reference vectors, but im having issues with it. What I need is the block y-1 and in front of the player. Just the 1 block.

 

Paxination

PHP:

public Location behindPlayer(Player player) {
        double rotation = (player.getLocation().getYaw() - 90) % 360;
        Block b = player.getLocation().clone().subtract(0, 1, 0).getBlock();
        if (rotation < 0) {
            rotation += 360.0;
        }
        if (0 <= rotation && rotation < 22.5) {
            return b.getRelative(BlockFace.NORTH).getLocation();
        } else if (22.5 <= rotation && rotation < 67.5) {
            return b.getRelative(BlockFace.NORTH_EAST).getLocation()
        } else if (67.5 <= rotation && rotation < 112.5) {
            return b.getRelative(BlockFace.EAST).getLocation();
        } else if (112.5 <= rotation && rotation < 157.5) {
            return b.getRelative(BlockFace.SOUTH_EAST).getLocation();
        } else if (157.5 <= rotation && rotation < 202.5) {
            return b.getRelative(BlockFace.SOUTH).getLocation();
        } else if (202.5 <= rotation && rotation < 247.5) {
            return b.getRelative(BlockFace._SOUTH_WEST).getLocation();
        } else if (247.5 <= rotation && rotation < 292.5) {
            return b.getRelative(BlockFace.WEST).getLocation();
        } else if (292.5 <= rotation && rotation < 337.5) {
           return b.getRelative(BlockFace.NORTH_WEST).getLocation() ;
        } else if (337.5 <= rotation && rotation < 360.0) {
            return b.getRelative(BlockFace.NORTH).getLocation();
        } else {
            return null;
        }
    }
}

 

Whats the point in .clone()? Other than its name sake "clone", why are you using it? Is it so the subtract(0,1,0) doesnt modify the actual location?