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JAVA = javac
RM = /bin/rm -f
all:
#${JAVA} src/Message.java
#${JAVA} src/Room.java
#${JAVA} src/User.java
${JAVA} src/ChatClient.java
${JAVA} src/ChatServer.java
clean:
${RM} *.class
${RM} src/*.class

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# A simple Chat program written in Java with NIO package
This program was written as a solution for an assignment given in
DCC-FCUP's [Networking and Communication](https://sigarra.up.pt/fcup/en/UCURR_GERAL.FICHA_UC_VIEW?pv_ocorrencia_id=445231) module.
The server implements a [multiplex model](http://tutorials.jenkov.com/java-nio/selectors.html) using [Java's NIO API](http://tutorials.jenkov.com/java-nio/index.html).
The protocol specified in the [assignment.pdf](assignment.pdf) (in Portuguese) is vaguely similar to IRC.
## Usage
1. Compile it with `make`
2. Run the server with a listening port as argument
```Shell
java ChatServer 31337
```
3. Run the client with the server IP address and the listening port
```Shell
java ChatClient 127.0.0.1 31337
```
## Tests
To test the sending of a fragmented message divided in various packages, use `netcat` with `<CTRL-D>`, as in
```Shell
/ni<CTRL-D>ck Chu<CTRL-D>ck No<CTRL-D>rris<ENTER>
```
To test the sending of various messages in a single package, you can try it with
```Shell
netcat localhost 31337 < test_package_input.txt
```
## Credits
Developed by [Diogo Cordeiro](https://www.diogo.site/) and [Hugo Sales](https://github.com/someonewithpc)
## License
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public
License along with this program, in the file "LICENSE". If not, see
<http://www.gnu.org/licenses/>.

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import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.InetSocketAddress;
import java.nio.CharBuffer;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.StandardCharsets;
/**
* This is the main class for the Chat Client
*/
public class
ChatClient
{
// Variáveis relacionadas com a interface gráfica --- * NÃO MODIFICAR *
JFrame frame = new JFrame("Chat Client");
private JTextField chatBox = new JTextField();
private JTextArea chatArea = new JTextArea();
// --- Fim das variáveis relacionadas com a interface gráfica
// Se for necessário adicionar variáveis ao objecto ChatClient, devem
// ser colocadas aqui
// Socket info
private SocketChannel client_socket;
// Decoder and enconder for transmitting text
private final Charset charset = StandardCharsets.UTF_8;
private final CharsetEncoder encoder = charset.newEncoder();
/**
* Método a usar para acrescentar uma string à caixa de texto
* * NÃO MODIFICAR *
*
* @param message
*/
public void
printMessage (final String message)
{
chatArea.append(message);
}
/**
* Constructor
*
* @param server server_host
* @param port server_port
* @throws IOException
*/
public ChatClient (String server, int port)
throws IOException
{
// Inicialização da interface gráfica --- * NÃO MODIFICAR *
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
panel.add(chatBox);
frame.setLayout(new BorderLayout());
frame.add(panel, BorderLayout.SOUTH);
frame.add(new JScrollPane(chatArea), BorderLayout.CENTER);
frame.setSize(500, 300);
frame.setVisible(true);
chatArea.setEditable(false);
chatBox.setEditable(true);
chatBox.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
try {
newMessage(chatBox.getText());
} catch (IOException ex) {
} finally {
chatBox.setText("");
}
}
});
frame.addWindowListener(new WindowAdapter() {
public void windowOpened(WindowEvent e) {
chatBox.requestFocus();
}
});
// --- Fim da inicialização da interface gráfica
// Se for necessário adicionar código de inicialização ao
// construtor, deve ser colocado aqui
// Socket information
try {
client_socket = SocketChannel.open();
client_socket.configureBlocking(true);
client_socket.connect(new InetSocketAddress(server, port));
} catch (IOException ex) {
// Fail graciously if the server is offline.
}
}
/**
* Instancia o ChatClient e arranca-o invocando o seu método run()
* * NÃO MODIFICAR *
*
* @param args
* @throws IOException
*/
public static void
main (String[] args)
throws IOException
{
ChatClient client = new ChatClient(args[0], Integer.parseInt(args[1]));
client.run();
}
/**
* Método invocado sempre que o utilizador insere uma mensagem
* na caixa de entrada
*
* @param message
* @throws IOException
*/
public void
newMessage (String message)
throws IOException
{
// PREENCHER AQUI com código que envia a mensagem ao servidor
client_socket.write(encoder.encode(CharBuffer.wrap(message + "\n")));
}
/**
* Método principal do objecto
*
* @throws IOException
*/
private void
run ()
throws IOException
{
// PREENCHER AQUI
try
{
while (!client_socket.finishConnect())
{;} /* Deliberately blank. */
}
catch (IOException ce)
{
System.err.println("Unable to connect to the server...");
System.exit(0);
return;
}
BufferedReader input_reader =
new BufferedReader(new InputStreamReader(client_socket.socket().getInputStream()));
// Listen loop
while (true)
{
String message = input_reader.readLine();
if (message == null)
{
break;
}
System.out.println("RECEIVED: " + message);
message = message.trim();
printMessage(Message.parse_string(message).toString(true));
int len = chatArea.getDocument().getLength(); // Length of chat text in lines
chatArea.setCaretPosition(len); // Scroll to bottom
}
System.out.println("Terminated.");
client_socket.close();
System.exit(0);
}
}

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import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Set;
import java.util.TreeSet;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* This is the main class for the Chat Server
*/
public class
ChatServer
{
// A pre-allocated buffer for the received data
private static final ByteBuffer buffer = ByteBuffer.allocate(16384);
// Decoder and encoder for transmitting text
private static final Charset charset = StandardCharsets.UTF_8;
private static final CharsetDecoder decoder = charset.newDecoder();
private static final CharsetEncoder encoder = charset.newEncoder();
// Regex for message process
private static final String REGEX_MSG_NEW_NICKNAME = "nick " + Message.REGEX_NICKNAME;
private static final String REGEX_MSG_JOIN = "join " + Message.REGEX_ROOM_NAME;
private static final String REGEX_MSG_LEAVE = "leave";
private static final String REGEX_MSG_BYE = "bye";
private static final String REGEX_MSG_PRIVATE = "priv " + Message.REGEX_NICKNAME + " " + Message.REGEX_TEXT;
// Users info
private static final HashMap<String, User> nickname_user = new HashMap<>();
private static final HashMap<String, Room> nickname_room = new HashMap<>();
/**
* Run the server
*
* @param args
*/
public static void
main (String[] args)
{
// Port to listen
int server_port = Integer.parseInt(args[0]);
try
{
// Instead of creating a ServerSocket, create a ServerSocketChannel
ServerSocketChannel ssc = ServerSocketChannel.open();
// Set it to non-blocking, so we can use select
ssc.configureBlocking(false);
// Get the Socket connected to this channel, and bind
// it to the listening port
ServerSocket ss = ssc.socket();
InetSocketAddress isa = new InetSocketAddress(server_port);
ss.bind(isa);
// Create a new Selector for selecting
Selector selector = Selector.open();
// Register the ServerSocketChannel, so we can listen
// for incoming connections
ssc.register(selector, SelectionKey.OP_ACCEPT);
System.out.println("Listening on port " + server_port);
while (true)
{
// See if we've had any activity -- either an incoming connection,
// or incoming data on an existing connection
int num = selector.select();
// If we don't have any activity, loop around and wait again
if (num == 0)
{
continue;
}
// Get the keys corresponding to the activity that has been
// detected, and process them one by one
Set<SelectionKey> keys = selector.selectedKeys();
for (SelectionKey key : keys)
{
// Get a key representing one of bits of I/O activity
// What kind of activity is it?
if (key.isAcceptable())
{
// It's an incoming connection. Register this socket with
// the Selector so we can listen for input on it
Socket s = ss.accept();
System.out.println("Got connection from " + s + ".");
// Make sure to make it non-blocking, so we can use a selector
// on it.
SocketChannel sc = s.getChannel();
sc.configureBlocking(false);
// Register it with the selector, for reading
sc.register(selector, SelectionKey.OP_READ, new User(sc));
}
else if (key.isReadable())
{
SocketChannel sc = null;
try
{
// It's incoming data on a connection -- process it
sc = (SocketChannel) key.channel();
boolean ok = processInput(key, sc);
// If the connection is dead, remove it from the selector
// and close it
if (!ok)
{
key.cancel();
close_client(key, sc);
}
}
catch (IOException ie)
{
// On exception, remove this channel from the selector
key.cancel();
close_client(key, sc);
}
}
}
// We remove the selected keys, because we've dealt with them.
keys.clear();
}
}
catch (IOException ie)
{
System.err.println(ie.getMessage());
}
}
/**
* Close a connection with a client
*
* @param key
* @param sc
*/
private static void
close_client (SelectionKey key, SocketChannel sc)
{
User sender = (User)key.attachment();
if (sender.get_state() == State.INSIDE)
{
Room room = sender.get_room();
room.left_user(sender);
TreeSet<User> user_list = room.get_users();
for (User user : user_list)
{
try
{
send_left_message(user, sender.get_nickname());
}
catch (IOException ie)
{
System.err.println("Error sending left message: " + ie);
}
}
if (user_list.size() == 0)
{
nickname_room.remove(room.get_name());
}
}
nickname_user.remove(sender.get_nickname());
key.cancel();
Socket s = sc.socket();
try
{
System.out.println("Closing connection to " + s);
sc.close();
}
catch (IOException ie)
{
System.err.println("Error closing socket " + s + ": " + ie);
}
}
/**
* Read a message from the socket and process it
*
* @param key
* @param sc
* @return boolean false if connection closed, true otherwise
* @throws IOException
*/
private static boolean
processInput (SelectionKey key, SocketChannel sc)
throws IOException
{
// Read the message to the buffer
buffer.clear();
sc.read(buffer);
buffer.flip();
// If no data, close the connection
if (buffer.limit() == 0)
{
return false;
}
// Decode and add to buffer
User sender = (User)key.attachment();
sender.add_to_buffer(decoder.decode(buffer).toString());
String instructions = sender.get_buffer().toString();
// // Print byte representation of incoming package
// for (final char c : instructions.toCharArray()) {
// System.out.print((int) c + " ");
// }
// System.out.println();
// We only want to process full instructions
if (!instructions.endsWith("\n"))
{
return true;
}
for (String instruction : instructions.split("\n"))
{
Matcher tokens;
if (instruction.startsWith("/"))
{
String cmd = instruction.substring(1).trim();
if ((tokens = Pattern.compile(REGEX_MSG_NEW_NICKNAME).matcher(cmd)).find())
{
send_nickname_command(sender, tokens.group(1));
}
else if ((tokens = Pattern.compile(REGEX_MSG_JOIN).matcher(cmd)).find())
{
send_join_command(sender, tokens.group(1));
}
else if (Pattern.matches(REGEX_MSG_LEAVE, cmd))
{
send_leave_command(sender);
}
else if (Pattern.matches(REGEX_MSG_BYE, cmd))
{
send_bye_command(key, sender);
}
else if ((tokens = Pattern.compile(REGEX_MSG_PRIVATE).matcher(cmd)).find())
{
send_private_command(
sender,
// Emitter
tokens.group(1),
// Message
tokens.group(2)
);
}
else if (cmd.startsWith("/"))
{
send_public_message(sender, cmd);
}
else
{
send_error_message(sender, "Unknown command.");
}
}
else if (instruction.length() != 0)
{
send_public_message(sender, instruction.trim());
}
sender.advance_buffer(instruction.length() + 1);
}
return true;
}
/**
* Helper function to send a message
*
* @param sc
* @param message
* @throws IOException
*/
private static void
send_message (SocketChannel sc, Message message)
throws IOException
{
sc.write(encoder.encode(CharBuffer.wrap(message.toString())));
}
/**
* Helper function to send a message
*
* @param receiver
* @param sender
* @param message_value
* @throws IOException
*/
private static void
send_message (User receiver, String sender, String message_value)
throws IOException
{
Message message = new Message(MessageType.MESSAGE, sender, message_value);
send_message(receiver.get_socket(), message);
}
/**
* Send error message
*
* @param receiver
* @param error_message
* @throws IOException
*/
private static void
send_error_message (User receiver, String error_message)
throws IOException
{
Message message = new Message(MessageType.ERROR, error_message);
send_message(receiver.get_socket(), message);
}
/**
* Send ok message
*
* @param receiver
* @throws IOException
*/
private static void
send_ok_message (User receiver)
throws IOException
{
Message message = new Message(MessageType.OK);
send_message(receiver.get_socket(), message);
}
/**
* Send newnick message
*
* @param receiver
* @param old_nickname
* @param new_nickname
* @throws IOException
*/
private static void
send_nickname_message (User receiver, String old_nickname, String new_nickname)
throws IOException
{
Message message = new Message(MessageType.NEW_NICKNAME, old_nickname, new_nickname);
send_message(receiver.get_socket(), message);
}
/**
* Send joined message
*
* @param receiver
* @param join_nickname
* @throws IOException
*/
private static void
send_joined_message (User receiver, String join_nickname)
throws IOException
{
Message message = new Message(MessageType.JOINED, join_nickname);
send_message(receiver.get_socket(), message);
}
/**
* Send left message
*
* @param receiver
* @param left_nickname
* @throws IOException
*/
private static void
send_left_message (User receiver, String left_nickname)
throws IOException
{
Message message = new Message(MessageType.LEFT, left_nickname);
send_message(receiver.get_socket(), message);
}
/**
* Send bye message
*
* @param receiver
* @throws IOException
*/
private static void
send_bye_message (User receiver)
throws IOException
{
Message message = new Message(MessageType.BYE);
send_message(receiver.get_socket(), message);
}
/**
* Send private message
*
* @param receiver
* @param sender
* @param message_value
* @throws IOException
*/
private static void
send_private_message (User receiver, String sender, String message_value)
throws IOException
{
Message message = new Message(MessageType.PRIVATE, sender, message_value);
send_message(receiver.get_socket(), message);
}
/**
* Send simple message
*
* @param sender
* @param message_value
* @throws IOException
*/
private static void
send_public_message (User sender, String message_value)
throws IOException
{
if (sender.get_state() == State.INSIDE)
{
Room sender_room = sender.get_room();
TreeSet<User> user_list = sender_room.get_users();
for (User user : user_list)
{
send_message(user, sender.get_nickname(), message_value);
}
}
else
{
send_error_message(sender, "You are not in a room.");
}
}
/**
* Send nick command
*
* @param sender
* @param nick
* @throws IOException
*/
private static void
send_nickname_command (User sender, String nick)
throws IOException
{
if (
// Allow to change to the current nick
// Only compare if the user already has a nickname
((sender.get_state() != State.INIT)
&& sender.get_nickname().equals(nick))
|| // Don't allow to set a nickname already in use
!nickname_user.containsKey(nick)
)
{
if (sender.get_state() == State.INIT)
{
sender.set_state(State.OUTSIDE);
}
if (sender.get_state() == State.INSIDE)
{
Room sender_room = sender.get_room();
TreeSet<User> user_list = sender_room.get_users();
for (User user : user_list)
{
if (user != sender)
{
send_nickname_message(user, sender.get_nickname(), nick);
}
}
}
nickname_user.remove(sender.get_nickname());
nickname_user.put(nick, sender);
send_ok_message(sender);
sender.set_nickname(nick);
}
else
{
send_error_message(sender, "There already is a user with nick " + nick);
}
}
/**
* Send join command
*
* @param sender
* @param room_name
* @throws IOException
*/
private static void
send_join_command (User sender, String room_name)
throws IOException
{
if (sender.get_state() == State.INIT)
{
send_error_message(sender, "You don't have a nickname.");
}
/*else if (sender.get_room().get_name().equals(room_name))
{
send_error_message(sender, "You already are in that room.");
}*/
else
{
// If already in a room, leave it first
if (sender.get_state() == State.INSIDE)
{
send_leave_command(sender);
}
// If room doesn't exist
if (!nickname_room.containsKey(room_name))
{
nickname_room.put(room_name, new Room(room_name));
}
// Notify
Room new_room = nickname_room.get(room_name);
TreeSet<User> current_room_user_list = new_room.get_users();
new_room.join_user(sender);
for (User user : current_room_user_list)
{
send_joined_message(user, sender.get_nickname());
}
send_ok_message(sender);
sender.set_room(new_room);
sender.set_state(State.INSIDE);
}
}
/**
* Send leave command
*
* @param sender
* @throws IOException
*/
private static void
send_leave_command (User sender)
throws IOException
{
if (sender.get_state() != State.INSIDE)
{
send_error_message(sender, "You are not in a room.");
}
else
{
Room room = sender.get_room();
room.left_user(sender);
TreeSet<User> user_list = room.get_users();
for (User user : user_list)
{
send_left_message(user, sender.get_nickname());
}
if (user_list.size() == 0)
{
nickname_room.remove(room.get_name());
}
send_ok_message(sender);
sender.set_state(State.OUTSIDE);
}
}
/**
* Send bye command
*
* @param key
* @param sender
* @throws IOException
*/
private static void
send_bye_command (SelectionKey key, User sender)
throws IOException
{
send_bye_message(sender);
close_client(key, sender.get_socket());
}
/**
* Send private message
*
* @param sender
* @param receiver
* @param message_value
* @throws IOException
*/
private static void
send_private_command (User sender, String receiver, String message_value)
throws IOException
{
if (sender.get_state() == State.INIT)
{
send_error_message(sender, "You don't have a nickname.");
}
else
{
if (nickname_user.containsKey(receiver))
{
send_ok_message(sender);
send_private_message(nickname_user.get(receiver), sender.get_nickname(), message_value);
}
else
{
send_error_message(sender, receiver + ": No such nickname online.");
}
}
}
}

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import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Type of the Message
*/
enum MessageType
{
OK, ERROR, MESSAGE, NEW_NICKNAME, JOINED, LEFT, BYE, PRIVATE
}
/**
* Message class
*/
public class
Message
{
public static final String REGEX_NICKNAME = "([^ .]+)";
public static final String REGEX_ROOM_NAME = "([^ .]+)";
public static final String REGEX_TEXT = "(.*)";
// Regex for command process
private static final String REGEX_CMD_OK = "OK";
private static final String REGEX_CMD_ERROR = "ERROR";
private static final String REGEX_CMD_MESSAGE = "MESSAGE " + REGEX_NICKNAME + " " + REGEX_TEXT;
private static final String REGEX_CMD_NEW_NICKNAME = "NEWNICK " + REGEX_NICKNAME + " " + REGEX_NICKNAME;
private static final String REGEX_CMD_JOINED = "JOINED " + REGEX_NICKNAME;
private static final String REGEX_CMD_LEFT = "LEFT " + REGEX_NICKNAME;
private static final String REGEX_CMD_BYE = "BYE";
private static final String REGEX_CMD_PRIVATE = "PRIVATE " + REGEX_NICKNAME + " " + REGEX_TEXT;
private final MessageType type;
// There are no getters for these two attributes, refer to toString
private final String token1;
private final String token2;
/**
* Constructor
*
* @param type
*/
public Message (MessageType type)
{
this.type = type;
this.token1 = "";
this.token2 = "";
}
/**
* Constructor
*
* @param type
* @param token1
*/
public Message (MessageType type, String token1)
{
this.type = type;
this.token1 = token1;
this.token2 = "";
}
/**
* Constructor
*
* @param type
* @param token1
* @param token2
*/
public Message (MessageType type, String token1, String token2)
{
this.type = type;
this.token1 = token1;
this.token2 = token2;
}
/**
* Message from String
* ONLY TO BE USED BY CHAT CLIENT (that is, command process and not
* message process as happens in the server)
*
* @param text
* @return Message
*/
public static Message
parse_string (String text)
{
MessageType type;
Matcher tokens;
String token1 = "";
String token2 = "";
if (Pattern.matches(REGEX_CMD_OK, text))
{
type = MessageType.OK;
}
else if (Pattern.matches(REGEX_CMD_ERROR, text))
{
type = MessageType.ERROR;
}
else if ((tokens = Pattern.compile(REGEX_CMD_MESSAGE).matcher(text)).find())
{
type = MessageType.MESSAGE;
token1 = tokens.group(1); // Emitter
token2 = tokens.group(2); // Message
}
else if ((tokens = Pattern.compile(REGEX_CMD_NEW_NICKNAME).matcher(text)).find())
{
type = MessageType.NEW_NICKNAME;
token1 = tokens.group(1); // Old nickname
token2 = tokens.group(2); // New nickname
}
else if ((tokens = Pattern.compile(REGEX_CMD_JOINED).matcher(text)).find())
{
type = MessageType.JOINED;
token1 = tokens.group(1);
}
else if ((tokens = Pattern.compile(REGEX_CMD_LEFT).matcher(text)).find())
{
type = MessageType.LEFT;
token1 = tokens.group(1);
}
else if (Pattern.matches(REGEX_CMD_BYE, text))
{
type = MessageType.BYE;
}
else if ((tokens = Pattern.compile(REGEX_CMD_PRIVATE).matcher(text)).find())
{
type = MessageType.PRIVATE;
token1 = tokens.group(1); // Emitter
token2 = tokens.group(2); // Message
}
else
{
type = MessageType.ERROR;
}
return new Message(type, token1, token2);
}
/**
* @return MessageType
*/
public MessageType
get_type ()
{
return this.type;
}
/**
* @return String
*/
@Override
public String
toString ()
{
return this.toString(false);
}
/**
* @param pretty
* @return String
*/
public String
toString (boolean pretty)
{
String output = "";
switch (this.type)
{
case OK:
if (pretty)
{
output = "Command successful.";
}
else
{
output = "OK";
}
break;
case ERROR:
if (pretty)
{
output = "Error. " + this.token1;
}
else
{
output = "ERROR";
}
break;
case MESSAGE:
if (pretty)
{
output = this.token1 + ": " + this.token2;
}
else
{
output = "MESSAGE " + this.token1 + " " + this.token2;
}
break;
case NEW_NICKNAME:
if (pretty)
{
output = this.token1 + " is now known as " + this.token2;
}
else
{
output = "NEWNICK " + this.token1 + " " + this.token2;
}
break;
case JOINED:
if (pretty)
{
output = this.token1 + " has joined the room.";
}
else
{
output = "JOINED " + this.token1;
}
break;
case LEFT:
if (pretty)
{
output = this.token1 + " left the room.";
}
else
{
output = "LEFT " + this.token1;
}
break;
case BYE:
if (pretty)
{
output = "Disconnected...";
}
else
{
output = "BYE";
}
break;
case PRIVATE:
if (pretty)
{
output = "<" + this.token1 + ">: " + this.token2;
}
else
{
output = "PRIVATE " + this.token1 + " " + this.token2;
}
break;
}
return output + "\n";
}
}

58
src/Room.java Normal file
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@ -0,0 +1,58 @@
import java.util.TreeSet;
/**
* Room class
*/
public class
Room
{
private final TreeSet<User> users;
private final String name;
/**
* Constructor
*
* @param name
*/
public Room (String name)
{
this.users = new TreeSet<>();
this.name = name;
}
/**
* @return TreeSet<User>
*/
public TreeSet<User>
get_users ()
{
return this.users;
}
/**
* @param user
*/
public void
join_user (User user)
{
this.users.add(user);
}
/**
* @param user
*/
public void
left_user (User user)
{
this.users.remove(user);
}
/**
* @return String
*/
public String
get_name ()
{
return this.name;
}
}

137
src/User.java Normal file
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@ -0,0 +1,137 @@
import java.nio.channels.SocketChannel;
/**
* User state
*/
enum State
{
INIT, OUTSIDE, INSIDE
}
/**
* User class
*/
public class
User
implements Comparable<User>
{
private String nickname;
private State state = State.INIT;
private Room room;
private final SocketChannel socket;
private StringBuilder buffer = new StringBuilder();
/**
* Constructor
*
* @param socket
*/
public User (SocketChannel socket)
{
this.socket = socket;
}
/**
* Comparator
*
* @param other
* @return int
*/
@Override
public int
compareTo (User other)
{
return this.nickname.compareTo(other.nickname);
}
/**
* @return String
*/
public String
get_nickname ()
{
return this.nickname;
}
/**
* @param nickname
*/
public void
set_nickname (String nickname)
{
this.nickname = nickname;
}
/**
* @return State
*/
public State
get_state ()
{
return this.state;
}
/**
* @param state
*/
public void
set_state (State state)
{
this.state = state;
}
/**
* @return Room
*/
public Room
get_room ()
{
return this.room;
}
/**
* @param room
*/
public void
set_room (Room room)
{
this.room = room;
}
/**
* @return SocketChannel
*/
public SocketChannel
get_socket ()
{
return this.socket;
}
/**
* @param cmd
*/
public void
add_to_buffer (String cmd)
{
this.buffer.append(cmd);
}
/**
* @return String
*/
public StringBuilder
get_buffer ()
{
return this.buffer;
}
/**
* @param idx
*/
public void
advance_buffer (int idx)
{
this.buffer.delete(0, idx);
}
}

11
src/chat.iml Normal file
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@ -0,0 +1,11 @@
<?xml version="1.0" encoding="UTF-8"?>
<module type="JAVA_MODULE" version="4">
<component name="NewModuleRootManager" inherit-compiler-output="true">
<exclude-output />
<content url="file://$MODULE_DIR$">
<sourceFolder url="file://$MODULE_DIR$" isTestSource="false" />
</content>
<orderEntry type="inheritedJdk" />
<orderEntry type="sourceFolder" forTests="false" />
</component>
</module>

4
test_package_input.txt Normal file
View File

@ -0,0 +1,4 @@
/nick bomrapaz
/join sala
Bom dia!