CS 596 Client-Server Programming
Assignment 5 Comments

class SumServer 
	{
	static int  portNumber  =  4444;
	public static void main(String args[]) 
		{
		ServerSocket serverSocket;
		serverSocket = serverSocketOn( portNumber );

		Socket clientSocket = null;
		InputStream  fromClient;
		OutputStream  toClient;

		while ( true )
			{
			clientSocket  =  acceptClientRequestOn( serverSocket );
			fromClient =  inputStreamFromClient( clientSocket  );
			toClient  =  outputStreamToClient( clientSocket  );
			processClientRequest( fromClient, toClient  );
			}
		}
	protected static void processClientRequest( InputStream in, 
												OutputStream out )
		{
		SumHandler  adder  =  new  SumHandler( in, out);
		Thread  serverThread  =  new  Thread( adder, "Add" );
		serverThread.start();
		}


class SumHandler implements Runnable
	{
	protected ASCIIInputStream  cin;
	protected PrintStream  cout;

	public  SumHandler( InputStream in, OutputStream out )
		{
		cin     =  new ASCIIInputStream( in );
		cout   =  new PrintStream( out, false);
		}

	public void run ()
		{
		try
			{

			// Do server stuff in here

			}
		catch (IOException e) 
			{  // What to do here? }
		}
	}

VT100 terminals

HTTP

Controls all user interaction

Presentation Logic

Displays graphical output and processes user input

Computational Logic

Does computation tasks of the program

Information Logic

Accesses the information storage system

Determines how to access storage system

Determines what to store

Determines what to retrieve

Create a query to send to a database (for example)

Actually reads and writes data from storage devices