package TcpExamples;

import java.io.IOException;
import java.net.*;

/**
 * A server example that creates and dispatches a new thread to handle multiple
 * connections one after another, running in parallel.
 *
 * @author Don McGregor
 * @author Don Brutzman
 * @author MV3500 class
 */
public class TcpExample4DispatchServer {

    /**
     * Program invocation, execution starts here
     * @param args command-line arguments
     */
    public static void main(String[] args)
    {
        try {
            ServerSocket serverSocket = new ServerSocket(2317);
            TcpExample4HandlerThread handlerThread;
            Socket clientConnection;

            int connectionCount = 0; // state variable

            System.out.println(TcpExample4DispatchServer.class.getName() + " ready to accept socket connections...");
            while (true) // infinite loop
            {
                clientConnection = serverSocket.accept(); // block until connected

                connectionCount++; // unblocked, got another connection
                System.out.println("=============================================================");
                System.out.println(TcpExample4DispatchServer.class.getName() + ".handlerThread invocation for connection #" + connectionCount + "...");
                handlerThread = new TcpExample4HandlerThread(clientConnection);
                handlerThread.start(); // invokes the run() method in that object
                System.out.println(TcpExample4DispatchServer.class.getName() + ".handlerThread is launched, awaiting another connection...");
            }
        } catch (IOException e) {
            System.out.println("Problem with " + TcpExample4DispatchServer.class.getName() + " networking:"); // describe what is happening
            System.out.println("Error: " + e);
            // Provide more helpful information to user if exception occurs due to running twice at one time
            if (e instanceof java.net.BindException) {
                System.out.println("*** Be sure to stop any other running instances of programs using this port!");
            }
        }
        System.out.println("=============================================================");
    }
}