Java Socket

I am trying to open a socket and send a
query to a remote comp. It connects allright, but does not
respond to the query, not even with an error message - that's
the problem.

just fyi - the ultimate goal of this program is to find mashines
within given IP range and read their parameters (hostname, mac
address, etc.)

Thanks a bunch!

try {
input = new BufferedReader(new
InputStreamReader(System.in));
OutputStream out = socket.getOutputStream();

out.write (45);
System.out.println ("start reading");
BufferedReader din =
new BufferedReader(new InputStreamReader
(socket.getInputStream()));
System.out.println ("done creating object");
response = din.readLine();
System.out.println ("done reading");

System.out.print (response);
socket.close();
//}
}
catch (IOException e) {
System.out.println(e);
}