commit 619d47ae66c785ff41d4ed619030e1938a112fe5 Author: Diogo Cordeiro Date: Wed Dec 25 13:40:45 2019 +0000 dump solution diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..f288702 --- /dev/null +++ b/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..6ddfa37 --- /dev/null +++ b/Makefile @@ -0,0 +1,14 @@ +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 diff --git a/README.md b/README.md new file mode 100644 index 0000000..00472c4 --- /dev/null +++ b/README.md @@ -0,0 +1,45 @@ +# 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 ``, as in +```Shell + /nick Chuck Norris +``` +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 +. diff --git a/assignment.pdf b/assignment.pdf new file mode 100644 index 0000000..09c8b9e Binary files /dev/null and b/assignment.pdf differ diff --git a/src/ChatClient.java b/src/ChatClient.java new file mode 100644 index 0000000..1f075e2 --- /dev/null +++ b/src/ChatClient.java @@ -0,0 +1,181 @@ +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); + } +} diff --git a/src/ChatServer.java b/src/ChatServer.java new file mode 100644 index 0000000..49aa811 --- /dev/null +++ b/src/ChatServer.java @@ -0,0 +1,634 @@ +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 nickname_user = new HashMap<>(); + private static final HashMap 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 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_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_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_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 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_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."); + } + } + } +} diff --git a/src/Message.java b/src/Message.java new file mode 100644 index 0000000..52e61ee --- /dev/null +++ b/src/Message.java @@ -0,0 +1,253 @@ +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"; + } +} diff --git a/src/Room.java b/src/Room.java new file mode 100644 index 0000000..670d6f1 --- /dev/null +++ b/src/Room.java @@ -0,0 +1,58 @@ +import java.util.TreeSet; + +/** + * Room class + */ +public class +Room +{ + private final TreeSet users; + private final String name; + + /** + * Constructor + * + * @param name + */ + public Room (String name) + { + this.users = new TreeSet<>(); + this.name = name; + } + + /** + * @return TreeSet + */ + public TreeSet + 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; + } +} diff --git a/src/User.java b/src/User.java new file mode 100644 index 0000000..3b3af00 --- /dev/null +++ b/src/User.java @@ -0,0 +1,137 @@ +import java.nio.channels.SocketChannel; + +/** + * User state + */ +enum State +{ + INIT, OUTSIDE, INSIDE +} + +/** + * User class + */ +public class +User +implements Comparable +{ + 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); + } +} diff --git a/src/chat.iml b/src/chat.iml new file mode 100644 index 0000000..e8a8ece --- /dev/null +++ b/src/chat.iml @@ -0,0 +1,11 @@ + + + + + + + + + + + diff --git a/test_package_input.txt b/test_package_input.txt new file mode 100644 index 0000000..6f94974 --- /dev/null +++ b/test_package_input.txt @@ -0,0 +1,4 @@ +/nick bomrapaz +/join sala +Bom dia! +