title: Can a ServerSocket and a Socket use one same port?
body: <p><br>
  Now I want to use a serversocket to listen port x, in the same time I want to use the port x to establish a socket to other serversocket, that means there is a serversocket and a socket will use one same port, is that possible?<br>
  I know for socket, it is four tuple, one port can have multiple socket, but for a socket and serversocket?<br>
  thank you for your attention!</p>