Starting Network Programming in Java - An Introduction to Network Programming with Java - page 16

catch(IOException ioEx)
{
ioEx.printStackTrace();
}
fi nally
{
try
{
System.out.println(
"\n* Closing connection… *");
link.close(); //Step 5.
}
catch(IOException ioEx)
{
System.out.println(
"Unable to disconnect!");
System.exit(1);
}
}
}
}
Setting up the corresponding client involves four steps…
1. Establish a connection to the server.
We create a Socket object, supplying its constructor with the following two
arguments:
￿ the server's IP address (of type InetAddress );
￿ the appropriate port number for the service.
(The port number for server and client programs must be the same, of course!)
For simplicity's sake, we shall place client and server on the same host, which
will allow us to retrieve the IP address by calling static method getLocalHost of
class InetAddress . For example:
Socket link =
new Socket(InetAddress.getLocalHost(),1234);
2. Set up input and output streams.
These are set up in exactly the same way as the server streams were set up (by call-
ing methods getInputStream and getOutputStream of the Socket object that was cre-
ated in step 2).
3. Send and receive data.
The Scanner object at the client end will receive messages sent by the PrintWriter
object at the server end, while the PrintWriter object at the client end will send mes-
sages that are received by the Scanner object at the server end (using methods next-
Line and println respectively).