The definition of available for LineNumberInputStream is

    public int available() throws IOException {
return (pushBack == -1) ? super.available() : super.available() + 1;
    }

but it should be

    public int available() throws IOException {
return (pushBack == -1) ? super.available()/2 : super.available()/2 + 1;
    }

    because if the contained stream can supply n bytes it might turn out
    that LineNumberInputStream can supply only n/2 bytes if the n bytes
    are a pile of \\r\\n pairs, right?