Convert IP between IPv4 and numerical format in java

Question

An IPv4 can have more representations: as string (a.b.c.d) or numerical (as an unsigned int of 32 bits). (Maybe other, but I will ignore them.)

Is there any

Answer 1

I would suggest:

long ip2long(){
    ByteBuffer buffer = ByteBuffer.allocate(Long.BYTES).order(ByteOrder.BIG_ENDIAN);
    buffer.put(new byte[] { 0,0,0,0 });
    buffer.put(socket.getInetAddress().getAddress());
    buffer.position(0);
    return buffer.getLong();
}