import java.rmi.Naming;
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

public class ChatServerImpl extends UnicastRemoteObject implements ChatServer
{
	private static class ChatMsg
	{
		private int id;
		private String msg;
		
		public ChatMsg (int i, String m)
		{
			id = i;
			msg = m;
		}
		
		public int getId ()
		{
			return id;
		}
		
		public String getMsg ()
		{
			return msg;
		}
		
		public String toString ()
		{
			return "" + id + "..." + msg;
		}
	}
	
	private List msgs = new LinkedList ();
	private int nextId = 0;
	
	public synchronized void send (String name, String text) throws RemoteException
	{
		msgs.add (new ChatMsg (nextId++, name + ": " + text));
	}

	public synchronized String get (int id) throws RemoteException
	{
		Iterator iter = msgs.iterator ();
		
		while (iter.hasNext ())
		{
			ChatMsg cm = (ChatMsg) iter.next ();

			if (cm.id == id)
				return cm.msg;
		}
		
		return null;
	}
	
	public synchronized void disconnect (String name) throws RemoteException
	{
		msgs.add (new ChatMsg (nextId++, "<<" + name + " leaves the chat>>"));
	}
	
	public synchronized void connect (String name) throws RemoteException
	{
		msgs.add (new ChatMsg (nextId++, "<<" + name + " enters the chat>>"));
	}

	public ChatServerImpl () throws RemoteException
	{
		super ();
	}
	
	public static void main (String[] args)
	{
		try
		{
			ChatServerImpl server = new ChatServerImpl ();
			Naming.rebind ("//localhost:1099/ChatServer", server);
			System.out.println ("Ready for connections...");
		} 
		catch (Exception e)
		{
			e.printStackTrace();
		}
	}
}