1. A Chat Server DBI – Representation and Management of Data on the Internet

2. A Chat Server Example Gives an example of how to combine the client and the server application into one combined system The Chat application gives a group of remote users the ability to ‘talk’ to each other through a server

3. A Real Chat Room Commercials advertisements

4. Chat Server Listens on a port Accepts connections Spawns threads, one per connection Receives a message from one client Dispatches it to all clients

5. The Objects of the Server ChatServer –main ClientHandler –one per connection –threaded Dispatcher –vector

6. Chat Server Objects (Diagram) ChatServer ClientHandler Dispatcher Socket

7. ClientHandler In the running loop: –Generates filter streams –Reads a message line –Sends the messages to the dispatcher On another client message: –Get the message from the dispatcher –Sends the message to the client using the socket to the client

8. Dispatcher Keeps a list of all client handlers On a client message (sends the message to all clients): –Accepts a String and an identifying integer –Enumerates down all client handlers and calls each one’s send() method

9. ChatServer Creates a new ServerSocket Creates a new Dispatcher Listens for connections When connection received, creates a new ClientHandler and starts it as a new thread Adds it to the Dispatcher

10. The Code ChatClient.java ChatServer.java ClientHandler.java Dispatcher.java