I am trying to make a game as such:
A single server with multiple java and/or java clients… oh hell- I’m trying to create a grid-based mmo card game where multiple java applets or clients connect to a single server.
The first step I want to take in learning about clients and servers is to have a simple, two-client and single-server setup where player one and player two can see the other’s x and y mouse coordinates as target images on each client’s screen. I’m thinking that both clients connect to the server, the server giving each player a different colored target. Perhaps it can support more than two people but I just want it to be simple so I can learn from it.
The next step is to create the game. I don’t know much about servers, clients, packets, ect., but as an educated guess:
- the Server (physical) holds each player’s total cards, current deck, saved decks, profile information, ect.
- the Client connects to the server and is fully dynamic so that it saves Nothing on the client’s machine
- the Client sends requests information depending on the current page of the client: Intro Page, Lobby and Chat, and Game. (perhaps more)
I’ve heard that UDP is better for action MMO’s like Wow and Rag online, but TCP/IP requests only one packet at a time and doesn’t move forward until the packet is sent. So I’m sure that I’d go with TCP/IP.
As far as I’ve seen, studied (Copy-Paste-Run-Study Code), I’ve been given this group of example codes for The Multithreaded Server and Multithreaded Client:
import java.awt.;
import java.awt.event.;
import java.net.;
import java.io.;
import java.util.*;
public class Server_Threaded extends Frame implements ActionListener, WindowListener {
//***** Mulit-threaded server, accepts multiple messages
// expected to be run on hawk-cs.cs.unc.edu:8901
protected String DEFAULT_HOST = “hawk-cs.cs.unc.edu”;
protected int DEFAULT_PORT = 8901;
String host;
int port;
ListenServer listen;
TextField hostDisplay, portDisplay;
TextArea logDisplay, msgDisplay;
Panel topPanel;
Panel middlePanel;
Panel buttonPanel;
Button listenButton, quitButton;
// ************** Server_Threaded
public Server_Threaded () {
super ( "Server_Threaded " );
buildUI ();
} // end constructor
// ************** main
public static void main ( String [ ] args ) {
Server_Threaded server = new Server_Threaded ();
} // end main
//*********** Interface Methods ***********
//**** ActionListener methods
public void actionPerformed ( ActionEvent e ) {
Object s = e.getSource();
// *** process Button actions
if ( s instanceof Button ) {
if ( s == listenButton ) {
listen = new ListenServer ( this );
listen.start ();
} // end listenButton
if ( s == quitButton ) {
hide ();
dispose ();
} // end quitButton
} // end process Button actions
} // end actionPerformed
//**** WindowListener methods
public void windowActivated ( WindowEvent e ) {
}
public void windowDeactivated ( WindowEvent e ) {
}
public void windowOpened ( WindowEvent e ) {
}
public void windowClosed ( WindowEvent e ) {
}
public void windowClosing ( WindowEvent e ) {
hide ();
dispose ();
}
public void windowIconified ( WindowEvent e ) {
}
public void windowDeiconified ( WindowEvent e ) {
}
//*********** Utility Methods ***********
// ************** buildUI
private void buildUI () {
try {
InetAddress here = InetAddress.getLocalHost ();
host = here.getHostName ();
}
catch (UnknownHostException e) { ;}
hostDisplay = new TextField ( host, 30 );
portDisplay = new TextField ( Integer.toString ( DEFAULT_PORT ), 4 );
topPanel = new Panel ();
topPanel.setLayout ( new GridLayout ( 2, 1 ) );
topPanel.add ( hostDisplay );
topPanel.add ( portDisplay );
logDisplay = new TextArea ( 40, 10 );
msgDisplay = new TextArea ( 40, 10 );
middlePanel = new Panel ();
middlePanel.setLayout ( new GridLayout ( 2, 1 ) );
middlePanel.add ( logDisplay );
middlePanel.add ( msgDisplay );
listenButton = new Button ( "Listen" );
quitButton = new Button ( "Quit" );
listenButton.addActionListener ( this );
quitButton.addActionListener ( this );
buttonPanel = new Panel ( );
buttonPanel.add ( listenButton );
buttonPanel.add ( quitButton );
add ( "North", topPanel );
add ( "Center", middlePanel );
add ( "South", buttonPanel );
resize ( 400, 450 );
show ();
} // end buildUI
} // end Server_Threaded
// ******************** ListenServer ***********
class ListenServer extends Thread {
Server_Threaded source;
ServerSocket listenSocket;
int port;
Socket connection;
HandleServer handle;
boolean again = true;
// ************** ListenServer constructor
ListenServer ( Server_Threaded s) {
super ();
source = (Server_Threaded ) s;
} // end constructor
// ************** run
public void run () {
if ( ! ( source.portDisplay.getText () ).equals ( "" ) ) port = Integer.parseInt ( source.portDisplay.getText () );
else port = source.DEFAULT_PORT;
try {
listenSocket = new ServerSocket ( port );
source.logDisplay.setText ( "Server started:\n listening on port " + port + "\n\n" );
while ( true ) {
Socket connection = listenSocket.accept();
HandleServer handleServer = new HandleServer ( connection, source );
handleServer.start ();
} // end while
} catch ( IOException e ) {
e.printStackTrace ();
source.logDisplay.setText ( "Error is opening ServerSocket\n" );
System.exit ( 1 );
} // end catch
} // end run
} // end ListenServer
/******************************** HandleServer ***********/
class HandleServer extends Thread {
Server_Threaded source;
Socket connection;
InputStream inStream;
DataInputStream inDataStream;
OutputStream outStream;
DataOutputStream outDataStream;
String message;
// ************** HandleServer constructor
HandleServer ( Socket socket, Server_Threaded s) {
super ();
connection = socket;
source = s;
} // end constructor
// ************** run
public void run () {
String stringIn, stringOut;
boolean again = true;
InetAddress inet = connection.getInetAddress ();
String origin = inet.getHostName ();
int originport = connection.getPort ();
source.logDisplay.appendText ( "Adding Client: \n "+origin+":"+originport+"\n\n" );
try {
outStream = connection.getOutputStream ();
outDataStream = new DataOutputStream ( outStream );
inStream = connection.getInputStream ();
inDataStream = new DataInputStream ( inStream );
while ( true ) {
message = inDataStream.readUTF ();
source.logDisplay.appendText ( " Message, below, received\n" );
source.msgDisplay.setForeground ( Color.red );
source.msgDisplay.setText ( message );
outDataStream.writeUTF ( message );
source.logDisplay.appendText ( " Message returned to client \n\n" );
} // end while
} // end try
catch ( EOFException except ) {
source.logDisplay.appendText ( " Connection closed by Client\n\n" );
try {
connection.close ();
return;
}
catch ( IOException e ) {
e.printStackTrace ();
return;
} // end IOException
} // end catch EOFException
catch ( IOException e ) {
source.logDisplay.appendText ( " Connection closed abormally\n" );
e.printStackTrace ();
return;
} // end catch IOException
} // end run
} // end HandleServer
-AND THE CLIENT-
import java.awt.;
import java.awt.event.;
import java.net.;
import java.io.;
import java.util.*;
public class Client_Threaded extends Frame implements ActionListener, WindowListener {
//***** Mulit-threaded client, sends and receives multiple messages
// expected to connect to server on hawk-cs.cs.unc.edu:8901
protected String DEFAULT_HOST = “hawk-cs.cs.unc.edu”;
protected int DEFAULT_PORT = 8901;
String host;
int port;
ConnectServer connection;
TextField hostDisplay, portDisplay;
TextArea logDisplay, msgDisplay;
Panel topPanel;
Panel middlePanel;
Panel buttonPanel;
Button connectButton, sendButton, cancelButton, quitButton;
// ************** Client_Threaded
public Client_Threaded () {
super ( "Client_Threaded " );
buildUI ();
} // end constructor
// ************** main
public static void main ( String [ ] args ) {
Client_Threaded client = new Client_Threaded ();
} // end main
//*********** Interface Methods ***********
//**** ActionListener methods
public void actionPerformed ( ActionEvent e ) {
Object s = e.getSource();
// *** process Button actions
if ( s instanceof Button ) {
if ( s == connectButton ) {
connection = new ConnectServer ( this );
connection.start ();
} // end connectButton
if ( s == sendButton ) {
connection.sendReceive ();
} // end sendButton
if ( s == cancelButton ) {
msgDisplay.setText ( "" );
} // end cancelButton
if ( s == quitButton ) {
logDisplay.appendText ( "Closing connection and quitting\n" );
connection.closeConnection ();
try {Thread.sleep ( 2000 );} catch ( InterruptedException except) {;}
hide ();
dispose ();
System.exit ( 0 );
} // end quitButton
} // end process Button actions
} // end actionPerformed
//**** WindowListener methods
public void windowActivated ( WindowEvent e ) {
}
public void windowDeactivated ( WindowEvent e ) {
}
public void windowOpened ( WindowEvent e ) {
}
public void windowClosed ( WindowEvent e ) {
}
public void windowClosing ( WindowEvent e ) {
hide ();
dispose ();
System.exit(0);
}
public void windowIconified ( WindowEvent e ) {
}
public void windowDeiconified ( WindowEvent e ) {
}
//*********** Utility Methods ***********
// ************** buildUI
private void buildUI () {
try {
InetAddress here = InetAddress.getLocalHost ();
host = here.getHostName ();
}
catch (UnknownHostException e) { ;}
hostDisplay = new TextField ( host, 30 );
portDisplay = new TextField ( Integer.toString ( DEFAULT_PORT ), 4 );
topPanel = new Panel ();
topPanel.setLayout ( new GridLayout ( 2, 1 ) );
topPanel.add ( hostDisplay );
topPanel.add ( portDisplay );
logDisplay = new TextArea ( 40, 10 );
msgDisplay = new TextArea ( 40, 10 );
msgDisplay.setText ("Default message.");
middlePanel = new Panel ();
middlePanel.setLayout ( new GridLayout ( 2, 1 ) );
middlePanel.add ( logDisplay );
middlePanel.add ( msgDisplay );
connectButton = new Button ( "Connect" );
sendButton = new Button ( "Send" );
cancelButton = new Button ( "Cancel" );
quitButton = new Button ( "Quit" );
connectButton.addActionListener ( this );
sendButton.addActionListener ( this );
cancelButton.addActionListener ( this );
quitButton.addActionListener ( this );
buttonPanel = new Panel ( );
buttonPanel.add ( connectButton );
buttonPanel.add ( sendButton );
buttonPanel.add ( cancelButton );
buttonPanel.add ( quitButton );
add ( "North", topPanel );
add ( "Center", middlePanel );
add ( "South", buttonPanel );
resize ( 400, 450 );
show ();
} // end buildUI
} // end Server_Threaded
// ************************ ConnectServer Class ************************
class ConnectServer extends Thread {
Client_Threaded source;
String host;
int port;
Socket connection;
InputStream inStream;
DataInputStream inDataStream;
OutputStream outStream;
DataOutputStream outDataStream;
String message;
public static final String DEFAULT_HOST = “hawk-cs.cs.unc.edu”;
public static final int DEFAULT_PORT = 8901;
// ************** ConnectServer
ConnectServer ( Client_Threaded c) {
super ();
source = (Client_Threaded ) c;
connectServer ();
} // end constructor
// ************** run
public void run () {
} // end run
// ************** connectServer
public void connectServer ( ) {
host = source.hostDisplay.getText ();
if ( host.equals ("" ) ) host = source.DEFAULT_HOST;
if ( ! ( source.portDisplay.getText () ).equals ( "" ) ) port = Integer.parseInt ( source.portDisplay.getText () );
else port = source.DEFAULT_PORT;
try {
connection = new Socket ( host, port );
outStream = connection.getOutputStream ();
outDataStream = new DataOutputStream ( outStream );
inStream = connection.getInputStream ();
inDataStream = new DataInputStream ( inStream );
source.logDisplay.setText ( "Socket created: \n connecting to server "+host+":"+port+"\n\n" );
} // end try
catch ( IOException except) {
source.logDisplay.setText ( "Error connecting to server\n" );
except.printStackTrace ();
System.exit ( 1 );
} // end catch
} // end connectServer
// ************** sendReceive
public void sendReceive () {
try {
message = source.msgDisplay.getText ();
outDataStream.writeUTF ( message );
source.logDisplay.appendText ( "Message, below, sent to Server\n" );
source.msgDisplay.setText ( "" );
source.msgDisplay.setForeground ( Color.red );
message = inDataStream.readUTF ();
source.msgDisplay.appendText ( message );
source.logDisplay.appendText ( " Message returned from server\n\n" );
} // end try for input
catch ( EOFException except ) {
source.logDisplay.appendText ( "EOF received\n" );
closeConnection ();
} // end catch IOException
catch ( IOException e ) {
source.logDisplay.appendText ( "IOException\n" );
e.printStackTrace ();
return;
} // end catch IOException
} // end sendReceive
// ************** closeConnection
public void closeConnection () {
try {
connection.close ();
} catch ( IOException except ) {
source.logDisplay.appendText ( " Error clossing conncetion\n" );
except.printStackTrace ();
}
} // end closeConnection
} // end ConnectServer
So will i be using a client-server group like this or … where can I learn to do what I’ve set out to do?
