tipgame.net
Class GameConnections

java.lang.Object
  tipgame.net.GameConnections

public class GameConnections
extends java.lang.Object

This is used to receive and transmit data for consistency. The server is the authority of all information. The server sends regular updates and sends a common clock sample. Upon a client connecting, the server sends:

1. id of the client as an int
2. keyboard array
3. mouse array
4. message array
   When the server starts running, at each frame advance it reads from each client if available:
   1. keyboard
   2. mouse
   3. message
   then it sends to each client:
   1. the current time in seconds as a double
      if any of the keyboard or mouse information has changed, it sends the complete:
      1. keyboard array
      2. mouse array
      3. message array
   The current time is used to keep the clocks in sync. *

   Author:

   Jam Jenkins

   Nested Class Summary

   (package private) class

   GameConnections.WriterThread repeatedly writes to the clients

   Field Summary

   private boolean[]	activeStreams the state of the game connections to the server.
   private double	currentTime the global clock time in seconds.
   private java.lang.String	gameName name of the game
   private boolean	hasReadClients dirty bit indicating if the server has read new information from the clients.
   protected java.io.ObjectInputStream[]	in all connections inbound.
   private boolean	isPaused the state of the advancing of the game
   private Keyboard[]	keyboard all of the keyboards of the computers connected
   private java.lang.Object[]	message currently unused
   private Mouse[]	mouse all of the mouses of the computers connected
   private java.io.ObjectOutputStream[]	out all connections outbound.
   private java.lang.String	sessionName name of this session
   static int	TIME_BETWEEN_UPDATES time between sending updates to the clients
   private java.util.Timer	timer used to repeatedly write to the clients

   Constructor Summary

   GameConnections(java.lang.String gameName, java.lang.String sessionName, int players)
   constructs a server without blocking.

   Method Summary

   boolean	addConnection(java.io.ObjectOutputStream outStream, java.io.ObjectInputStream inStream) adds a connection to the server's list of clients.
   private void	clearInputDevices() clears all keys typed and mouses clicked to make sure they are only sent once.
   private void	flushClients() flushes what's currently in the output streams to the clients.
   private int	getFirstInactiveStream() determines where the next active stream should be added
   private void	handleBrokenConnection(int clientIndex) handles exceptions of broken connections.
   boolean	isActive() determines if any stream is active
   boolean	isFull() determines if all connections are alive
   private void	keepThreadAlive() necessary to keep the timer alive
   private void	readAvailable() reads any available new information from the clients.
   boolean	readAvailable(int clientIndex) reads what's available from the given client without blocking
   private void	sendFirstClientMessage() sends the information the client needs to start communications: keyboard array mouse array message array This method sends the arrays as complete objects the first time so that the existing objects can simply be updated on later transmissions.
   void	startThreads() starts the writing to the clients.
   void	write() writes to all clients if the game is not paused
   private void	writeClient(int clientIndex) writes an update to the client.
   private void	writeClients() writes an update to all client.

   Methods inherited from class java.lang.Object

   clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

   Field Detail

   keyboard

   private Keyboard[] keyboard

   all of the keyboards of the computers connected

   mouse

   private Mouse[] mouse

   all of the mouses of the computers connected

   isPaused

   private boolean isPaused

   the state of the advancing of the game

   TIME_BETWEEN_UPDATES

   public static final int TIME_BETWEEN_UPDATES

   time between sending updates to the clients

   See Also:

   Constant Field Values

   message

   private java.lang.Object[] message

   currently unused

   timer

   private java.util.Timer timer

   used to repeatedly write to the clients

   hasReadClients

   private boolean hasReadClients

   dirty bit indicating if the server has read new information from the clients. This is set to false after each server message is sent and set to true when any client information is read.

   in

   protected java.io.ObjectInputStream[] in

   all connections inbound. For clients this is just a single connection with the server and it is used to receive the array of mouses and keyboards and the current time to keep consistent clocks. For servers, there is one connection per client used to receive the individual keyboards and mouses.

   out

   private java.io.ObjectOutputStream[] out

   all connections outbound. For clients this is just a single connection with the server used to write this client's keyboard and mouse. For servers, there is one connection per client used to write the keyboard and mouse arrays and the current time.

   activeStreams

   private boolean[] activeStreams

   the state of the game connections to the server. True indicates everything is connecteda and active. False indicates disconnected or not yet connected streams.

   gameName

   private java.lang.String gameName

   name of the game

   sessionName

   private java.lang.String sessionName

   name of this session

   currentTime

   private double currentTime

   the global clock time in seconds. Starts at zero.

   Constructor Detail

   GameConnections

   public GameConnections(java.lang.String gameName,
                          java.lang.String sessionName,
                          int players)

   constructs a server without blocking.

   Parameters:

   gameName - the name of the game being played

   sessionName - the name of the current session for a given game

   players - the number of clients connecting

   Method Detail

   isFull

   public boolean isFull()

   determines if all connections are alive

   Returns:

   true if all connections are active, false otherw