Sending int through socket in Java

Question

What is the best possible way to send an int through a socket in Java? Right now I'm looking at

sockout.write((byte)( length >> 24 ));
sockout.write((byte)( (length << 8) >> 24 ));
sockout.write((byte)( (length << 16) >> 24 ));
sockout.write((byte)( (length << 24) >> 24 ));

and then trying to rebuild the int from bytes on the other side, but it doesn't seem to work. Any ideas?

Thanks.

Answer 1

There are other type of streams you can use, which can directly send integers. You can use DataOutputStream. Observe,

DataOutputStream out;
try {
    //create write stream to send information
    out=new DataOutputStream(sock.getOutputStream());
} catch (IOException e) { 
    //Bail out
}

out.writeInt(5);

Answer 2

Wrap your OutputStream with a DataOutputStream and then just use the writeInt() method.

Something else which may be useful is that on the other end you can wrap our InputStream in a DataInputStream and use readInt() to read an int back out.

Both classes also contain a number of other useful methods for reading and writing other raw types.

Answer 3

If you are sending small amounts of data, then encoding as character data (e.g. Integer.toString(length)) and decoding at the other end is not unreasonable.