Java IO.pdf - Nguyen Dang Binh

}
}
}
// This next line is problematic on non-ASCII systems
byte[] b = request.getBytes();
OutputStream out = s.getOutputStream();
InputStream in = s.getInputStream();
out.write(b);
out.flush();
StreamCopier.copy(in, System.out);
in.close();
out.close();
s.close();
}
catch (MalformedURLException e) {System.err.println(e);}
catch (IOException e) {System.err.println(e);}
Java I/O
For example, when SocketTyper connects to http://www.oreilly.com/, here is what you see:
% java SocketTyper http://www.oreilly.com/
HTTP/1.0 200 OK
Server: WN/1.15.1
Date: Sun, 09 Aug 1998 20:05:03 GMT
Last-modified: Fri, 07 Aug 1998 23:44:36 GMT
Content-type: text/html
Title: www.oreilly.com -- Welcome to O'Reilly & Associates!
Link: ; rev="Made"
Notice the header lines you didn't see in Example 5.1. When you use the URL class to
download a web page, the associated protocol handler never shows you the HTTP header.
5.4 Server Sockets
There are two ends to each connection: the client, which initiates the connection, and the
server, which responds to the connection. So far, we've only discussed the client side and
assumed that a server existed out there for the client to talk to. To implement a server, you
need to write a program that waits for other hosts to connect to it. A server socket binds to a
particular port on the local machine (the server); once it has successfully bound to a port, it
listens for incoming connection attempts from remote machines (the clients). When the server
detects a connection attempt, it accepts the connection. This creates a socket between the two
machines over which the client and the server communicate.
Many clients can connect to a port on the server simultaneously. Incoming data is
distinguished by the port to which it is addressed and the client host and port from which it
came. The server can tell for which service (like HTTP or FTP) the data is intended by
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