src/main/java/net/pterodactylus/irc/Connection.java

   1 /*
   2  * XdccDownloader - Connection.java - Copyright © 2013 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.irc;
  19
  20 import static com.google.common.base.Preconditions.checkState;
  21 import static java.util.concurrent.TimeUnit.SECONDS;
  22
  23 import java.io.BufferedReader;
  24 import java.io.Closeable;
  25 import java.io.EOFException;
  26 import java.io.IOException;
  27 import java.io.InputStream;
  28 import java.io.InputStreamReader;
  29 import java.io.OutputStream;
  30 import java.io.UnsupportedEncodingException;
  31 import java.net.InetAddress;
  32 import java.net.Socket;
  33 import java.net.UnknownHostException;
  34 import java.util.ArrayList;
  35 import java.util.List;
  36 import java.util.Map;
  37 import java.util.Set;
  38 import java.util.concurrent.TimeUnit;
  39 import javax.net.SocketFactory;
  40
  41 import net.pterodactylus.irc.event.ChannelJoined;
  42 import net.pterodactylus.irc.event.ChannelLeft;
  43 import net.pterodactylus.irc.event.ChannelMessageReceived;
  44 import net.pterodactylus.irc.event.ChannelNicknames;
  45 import net.pterodactylus.irc.event.ChannelNotJoined;
  46 import net.pterodactylus.irc.event.ChannelNotJoined.Reason;
  47 import net.pterodactylus.irc.event.ChannelNoticeReceived;
  48 import net.pterodactylus.irc.event.ChannelTopic;
  49 import net.pterodactylus.irc.event.ClientQuit;
  50 import net.pterodactylus.irc.event.ConnectionClosed;
  51 import net.pterodactylus.irc.event.ConnectionEstablished;
  52 import net.pterodactylus.irc.event.ConnectionFailed;
  53 import net.pterodactylus.irc.event.DccAcceptReceived;
  54 import net.pterodactylus.irc.event.DccSendReceived;
  55 import net.pterodactylus.irc.event.KickedFromChannel;
  56 import net.pterodactylus.irc.event.MotdReceived;
  57 import net.pterodactylus.irc.event.NicknameChanged;
  58 import net.pterodactylus.irc.event.NicknameInUseReceived;
  59 import net.pterodactylus.irc.event.NoNicknameGivenReceived;
  60 import net.pterodactylus.irc.event.PrivateMessageReceived;
  61 import net.pterodactylus.irc.event.PrivateNoticeReceived;
  62 import net.pterodactylus.irc.event.ReplyReceived;
  63 import net.pterodactylus.irc.event.UnknownReplyReceived;
  64 import net.pterodactylus.irc.util.RandomNickname;
  65 import net.pterodactylus.xdcc.util.io.BandwidthCountingInputStream;
  66 import net.pterodactylus.xdcc.util.io.BandwidthCountingOutputStream;
  67
  68 import com.google.common.base.Optional;
  69 import com.google.common.collect.Maps;
  70 import com.google.common.collect.Sets;
  71 import com.google.common.eventbus.EventBus;
  72 import com.google.common.io.Closeables;
  73 import com.google.common.primitives.Ints;
  74 import com.google.common.primitives.Longs;
  75 import com.google.common.util.concurrent.AbstractExecutionThreadService;
  76 import com.google.common.util.concurrent.Service;
  77 import org.apache.log4j.Logger;
  78
  79 /**
  80  * A connection to an IRC server.
  81  *
  82  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  83  */
  84 public class Connection extends AbstractExecutionThreadService implements Service {
  85
  86         /* The logger. */
  87         private static final Logger logger = Logger.getLogger(Connection.class.getName());
  88
  89         /** The event bus. */
  90         private final EventBus eventBus;
  91
  92         /** The socket factory. */
  93         private final SocketFactory socketFactory;
  94
  95         /** The hostname to connect to. */
  96         private final String hostname;
  97
  98         /** The port to connect to. */
  99         private final int port;
 100
 101         /** The nickname chooser. */
 102         private NicknameChooser nicknameChooser = new NicknameChooser() {
 103
 104                 @Override
 105                 public String getNickname() {
 106                         return RandomNickname.get();
 107                 }
 108         };
 109
 110         /** The nickname. */
 111         private String nickname = null;
 112
 113         /** The username. */
 114         private Optional<String> username = Optional.absent();
 115
 116         /** The real name. */
 117         private Optional<String> realName = Optional.absent();
 118
 119         /** The optional password for the connection. */
 120         private Optional<String> password = Optional.absent();
 121
 122         /** The connection handler. */
 123         private ConnectionHandler connectionHandler;
 124
 125         /** Whether the connection has already been established. */
 126         private boolean established;
 127
 128         /**
 129          * Creates a new connection.
 130          *
 131          * @param eventBus
 132          *              The event bus
 133          * @param socketFactory
 134          *              The socket factory
 135          * @param hostname
 136          *              The hostname of the IRC server
 137          * @param port
 138          *              The port number of the IRC server
 139          */
 140         public Connection(EventBus eventBus, SocketFactory socketFactory, String hostname, int port) {
 141                 this.eventBus = eventBus;
 142                 this.socketFactory = socketFactory;
 143                 this.hostname = hostname;
 144                 this.port = port;
 145         }
 146
 147         //
 148         // ACCESSORS
 149         //
 150
 151         /**
 152          * Returns the hostname of the remote end of the connection.
 153          *
 154          * @return The remote’s hostname
 155          */
 156         public String hostname() {
 157                 return hostname;
 158         }
 159
 160         /**
 161          * Returns the port number of the remote end of the connection.
 162          *
 163          * @return The remote’s port number
 164          */
 165         public int port() {
 166                 return port;
 167         }
 168
 169         /**
 170          * Returns whether this connection has already been established.
 171          *
 172          * @return {@code true} as long as this connection is established, {@code
 173          *         false} otherwise
 174          */
 175         public boolean established() {
 176                 return established;
 177         }
 178
 179         /**
 180          * Returns the nickname that is currently in use by this connection. The
 181          * nickname is only available once the connection has been {@link #start()}ed.
 182          *
 183          * @return The current nickname
 184          */
 185         public String nickname() {
 186                 return nickname;
 187         }
 188
 189         //
 190         // MUTATORS
 191         //
 192
 193         /**
 194          * Sets the nickname chooser. The nickname chooser is only used during the
 195          * creation of the connection.
 196          *
 197          * @param nicknameChooser
 198          *              The nickname chooser
 199          * @return This connection
 200          */
 201         public Connection nicknameChooser(NicknameChooser nicknameChooser) {
 202                 this.nicknameChooser = nicknameChooser;
 203                 return this;
 204         }
 205
 206         /**
 207          * Sets the username to use.
 208          *
 209          * @param username
 210          *              The username to use
 211          * @return This connection
 212          */
 213         public Connection username(String username) {
 214                 this.username = Optional.fromNullable(username);
 215                 return this;
 216         }
 217
 218         /**
 219          * Sets the real name to use.
 220          *
 221          * @param realName
 222          *              The real name to use
 223          * @return This connection
 224          */
 225         public Connection realName(String realName) {
 226                 this.realName = Optional.fromNullable(realName);
 227                 return this;
 228         }
 229
 230         /**
 231          * Sets the optional password for the connection.
 232          *
 233          * @param password
 234          *              The password for the connection
 235          * @return This connection
 236          */
 237         public Connection password(String password) {
 238                 this.password = Optional.fromNullable(password);
 239                 return this;
 240         }
 241
 242         //
 243         // ACTIONS
 244         //
 245
 246         /**
 247          * Returns the current rate of the connection’s incoming side.
 248          *
 249          * @return The current input rate (in bytes per second)
 250          */
 251         public long getInputRate() {
 252                 return (connectionHandler != null) ? connectionHandler.getInputRate() : 0;
 253         }
 254
 255         /**
 256          * Returns the current rate of the connection’s outgoing side.
 257          *
 258          * @return The current output rate (in bytes per second)
 259          */
 260         public long getOutputRate() {
 261                 return (connectionHandler != null) ? connectionHandler.getOutputRate() : 0;
 262         }
 263
 264         /**
 265          * Checks whether the given source is the client represented by this
 266          * connection.
 267          *
 268          * @param source
 269          *              The source to check
 270          * @return {@code true} if this connection represents the given source, {@code
 271          *         false} otherwise
 272          */
 273         public boolean isSource(Source source) {
 274                 return source.nick().isPresent() && source.nick().get().equals(nickname);
 275         }
 276
 277         /**
 278          * Joins the given channel.
 279          *
 280          * @param channel
 281          *              The channel to join
 282          * @throws IOException
 283          *              if an I/O error occurs
 284          */
 285         public void joinChannel(final String channel) throws IOException {
 286                 connectionHandler.sendCommand("JOIN", channel);
 287         }
 288
 289         /**
 290          * Sends a message to the given recipient, which may be a channel or another
 291          * nickname.
 292          *
 293          * @param recipient
 294          *              The recipient of the message
 295          * @param message
 296          *              The message
 297          * @throws IOException
 298          *              if an I/O error occurs
 299          */
 300         public void sendMessage(String recipient, String message) throws IOException {
 301                 connectionHandler.sendCommand("PRIVMSG", recipient, message);
 302         }
 303
 304         /**
 305          * Sends a DCC RESUME request to the given recipient.
 306          *
 307          * @param recipient
 308          *              The recipient of the request
 309          * @param filename
 310          *              The name of the file to resume
 311          * @param port
 312          *              The port number from the original DCC SEND request
 313          * @param position
 314          *              The position at which to resume the transfer
 315          * @throws IOException
 316          *              if an I/O error occurs
 317          */
 318         public void sendDccResume(String recipient, String filename, int port, long position) throws IOException {
 319                 connectionHandler.sendCommand("PRIVMSG", recipient, String.format("\u0001DCC RESUME %s %d %d\u0001", filename, port, position));
 320         }
 321
 322         /**
 323          * Closes this connection.
 324          *
 325          * @throws IOException
 326          *              if an I/O error occurs
 327          */
 328         public void close() throws IOException {
 329                 if (connectionHandler != null) {
 330                         connectionHandler.close();
 331                 }
 332         }
 333
 334         //
 335         // ABSTRACTEXECUTIONTHREADSERVICE METHODS
 336         //
 337
 338         @Override
 339         protected void startUp() throws IllegalStateException {
 340                 checkState(username.isPresent(), "username must be set");
 341                 checkState(realName.isPresent(), "realName must be set");
 342         }
 343
 344         @Override
 345         protected void run() {
 346
 347                 /* connect to remote socket. */
 348                 try {
 349                         Socket socket = socketFactory.createSocket(hostname, port);
 350                         socket.setSoTimeout((int) TimeUnit.MINUTES.toMillis(3));
 351                         connectionHandler = new ConnectionHandler(socket.getInputStream(), socket.getOutputStream());
 352
 353                         /* register connection. */
 354                         if (password.isPresent()) {
 355                                 connectionHandler.sendCommand("PASSWORD", password.get());
 356                         }
 357                         connectionHandler.sendCommand("USER", username.get(), "8", "*", realName.get());
 358                         nickname = nicknameChooser.getNickname();
 359                         connectionHandler.sendCommand("NICK", nickname);
 360
 361                 } catch (IOException ioe1) {
 362                         eventBus.post(new ConnectionFailed(this, ioe1));
 363                         return;
 364                 }
 365
 366                 /* now read replies and react. */
 367                 try {
 368                         /* some status variables. */
 369                         int oldConnectionStatus = 0;
 370                         int connectionStatus = 0;
 371                         boolean connected = true;
 372                         StringBuilder motd = new StringBuilder();
 373                         Set<Nickname> nicks = Sets.newHashSet();
 374
 375                         /* server modes. */
 376                         Map<String, String> nickPrefixes = Maps.newHashMap();
 377                         Set<Character> channelTypes = Sets.newHashSet();
 378
 379                         while (connected) {
 380                                 Reply reply = connectionHandler.readReply();
 381                                 eventBus.post(new ReplyReceived(this, reply));
 382                                 logger.trace(String.format("<< %s", reply));
 383                                 String command = reply.command();
 384                                 List<String> parameters = reply.parameters();
 385
 386                                 /* most common events. */
 387                                 if (command.equalsIgnoreCase("PRIVMSG")) {
 388                                         String recipient = parameters.get(0);
 389                                         String message = parameters.get(1);
 390                                         if (message.startsWith("\u0001") && message.endsWith("\u0001")) {
 391                                                 /* CTCP! */
 392                                                 handleCtcp(reply.source().get(), message);
 393                                         } else if (!channelTypes.contains(recipient.charAt(0))) {
 394                                                 eventBus.post(new PrivateMessageReceived(this, reply.source().get(), message));
 395                                         } else {
 396                                                 eventBus.post(new ChannelMessageReceived(this, recipient, reply.source().get(), message));
 397                                         }
 398
 399                                 } else if (command.equalsIgnoreCase("NOTICE")) {
 400                                         String recipient = parameters.get(0);
 401                                         String message = parameters.get(1);
 402                                         if (message.startsWith("\u0001") && message.endsWith("\u0001")) {
 403                                                 /* CTCP! */
 404                                                 handleCtcp(reply.source().get(), message);
 405                                         } else if (!channelTypes.contains(recipient.charAt(0))) {
 406                                                 eventBus.post(new PrivateNoticeReceived(this, reply));
 407                                         } else {
 408                                                 eventBus.post(new ChannelNoticeReceived(this, reply.source().get(), recipient, message));
 409                                         }
 410
 411                                 /* 43x replies are for nick change errors. */
 412                                 } else if (command.equals("431")) {
 413                                         eventBus.post(new NoNicknameGivenReceived(this, reply));
 414                                 } else if (command.equals("433")) {
 415                                         if (connectionStatus == 0) {
 416                                                 nickname = nicknameChooser.getNickname();
 417                                                 connectionHandler.sendCommand("NICK", nickname);
 418                                         } else {
 419                                                 eventBus.post(new NicknameInUseReceived(this, reply));
 420                                         }
 421
 422                                 /* client stuff. */
 423                                 } else if (command.equalsIgnoreCase("NICK")) {
 424                                         eventBus.post(new NicknameChanged(this, reply.source().get(), parameters.get(0)));
 425
 426                                 /* channel stuff. */
 427                                 } else if (command.equalsIgnoreCase("JOIN")) {
 428                                         eventBus.post(new ChannelJoined(this, parameters.get(0), reply.source().get()));
 429                                 } else if (command.equals("331")) {
 430                                         /* no topic is set. */
 431                                 } else if (command.equals("332")) {
 432                                         eventBus.post(new ChannelTopic(this, parameters.get(1), parameters.get(2)));
 433                                 } else if (command.equals("353")) {
 434                                         for (String nickname : parameters.get(3).split(" ")) {
 435                                                 if (nickPrefixes.containsKey(nickname.substring(0, 1))) {
 436                                                         nicks.add(new Nickname(nickname.substring(1), nickname.substring(0, 1)));
 437                                                 } else {
 438                                                         nicks.add(new Nickname(nickname, ""));
 439                                                 }
 440                                         }
 441                                 } else if (command.equals("366")) {
 442                                         eventBus.post(new ChannelNicknames(this, parameters.get(1), nicks));
 443                                         nicks.clear();
 444                                 } else if (command.equalsIgnoreCase("PART")) {
 445                                         eventBus.post(new ChannelLeft(this, parameters.get(0), reply.source().get(), getOptional(parameters, 1)));
 446                                 } else if (command.equalsIgnoreCase("QUIT")) {
 447                                         eventBus.post(new ClientQuit(this, reply.source().get(), parameters.get(0)));
 448
 449                                 /* common channel join errors. */
 450                                 } else if (command.equals("474")) {
 451                                         eventBus.post(new ChannelNotJoined(this, parameters.get(1), Reason.banned));
 452                                 } else if (command.equals("473")) {
 453                                         eventBus.post(new ChannelNotJoined(this, parameters.get(1), Reason.inviteOnly));
 454                                 } else if (command.equals("475")) {
 455                                         eventBus.post(new ChannelNotJoined(this, parameters.get(1), Reason.badChannelKey));
 456                                 } else if (command.equals("477")) {
 457                                         eventBus.post(new ChannelNotJoined(this, parameters.get(1), Reason.registeredNicknamesOnly));
 458
 459                                 /* basic connection housekeeping. */
 460                                 } else if (command.equalsIgnoreCase("PING")) {
 461                                         connectionHandler.sendCommand("PONG", getOptional(parameters, 0), getOptional(parameters, 1));
 462
 463                                 /* replies 001-004 don’t hold information but they have to be sent on a successful connection. */
 464                                 } else if (command.equals("001")) {
 465                                         connectionStatus |= 0x01;
 466                                 } else if (command.equals("002")) {
 467                                         connectionStatus |= 0x02;
 468                                 } else if (command.equals("003")) {
 469                                         connectionStatus |= 0x04;
 470                                 } else if (command.equals("004")) {
 471                                         connectionStatus |= 0x08;
 472
 473                                 /* 005 originally was a bounce message, now used to transmit useful information about the server. */
 474                                 } else if (command.equals("005")) {
 475                                         for (String parameter : parameters) {
 476                                                 if (parameter.startsWith("PREFIX=")) {
 477                                                         int openParen = parameter.indexOf('(');
 478                                                         int closeParen = parameter.indexOf(')');
 479                                                         if ((openParen != -1) && (closeParen != -1)) {
 480                                                                 for (int modeCharacterIndex = 1; modeCharacterIndex < (closeParen - openParen); ++modeCharacterIndex) {
 481                                                                         char modeCharacter = parameter.charAt(openParen + modeCharacterIndex);
 482                                                                         char modeSymbol = parameter.charAt(closeParen + modeCharacterIndex);
 483                                                                         nickPrefixes.put(String.valueOf(modeSymbol), String.valueOf(modeCharacter));
 484                                                                 }
 485                                                                 logger.debug(String.format("Parsed Prefixes: %s", nickPrefixes));
 486                                                         }
 487                                                 } else if (parameter.startsWith("CHANTYPES=")) {
 488                                                         for (int typeIndex = 10; typeIndex < parameter.length(); ++typeIndex) {
 489                                                                 channelTypes.add(parameter.charAt(typeIndex));
 490                                                         }
 491                                                         logger.debug(String.format("Parsed Channel Types: %s", channelTypes));
 492                                                 }
 493                                         }
 494
 495                                 /* 375, 372, and 376 handle the server’s MOTD. */
 496                                 } else if (command.equals("375")) {
 497                                         /* MOTD starts. */
 498                                         motd.append(parameters.get(1)).append('\n');
 499                                 } else if (command.equals("372")) {
 500                                         motd.append(parameters.get(1)).append('\n');
 501                                 } else if (command.equals("376")) {
 502                                         motd.append(parameters.get(1)).append('\n');
 503                                         eventBus.post(new MotdReceived(this, motd.toString()));
 504                                         motd.setLength(0);
 505
 506                                 } else if (command.equalsIgnoreCase("KICK")) {
 507                                         eventBus.post(new KickedFromChannel(this, parameters.get(0), reply.source().get(), parameters.get(1), getOptional(parameters, 2)));
 508
 509                                 /* okay, everything else. */
 510                                 } else {
 511                                         eventBus.post(new UnknownReplyReceived(this, reply));
 512                                 }
 513
 514                                 if ((connectionStatus == 0x0f) && (connectionStatus != oldConnectionStatus)) {
 515                                         /* connection succeeded! */
 516                                         established = true;
 517                                         eventBus.post(new ConnectionEstablished(this));
 518                                 }
 519                                 oldConnectionStatus = connectionStatus;
 520                         }
 521                         eventBus.post(new ConnectionClosed(this));
 522                 } catch (IOException ioe1) {
 523                         logger.warn("I/O error", ioe1);
 524                         eventBus.post(new ConnectionClosed(this, ioe1));
 525                 } catch (RuntimeException re1) {
 526                         logger.error("Runtime error", re1);
 527                         eventBus.post(new ConnectionClosed(this, re1));
 528                 } finally {
 529                         established = false;
 530                         logger.info("Closing Connection.");
 531                         try {
 532                                 Closeables.close(connectionHandler, true);
 533                         } catch (IOException ioe1) {
 534                                 /* will not be thrown. */
 535                         }
 536                 }
 537
 538         }
 539
 540         //
 541         // PRIVATE METHODS
 542         //
 543
 544         /**
 545          * Handles a CTCP message.
 546          *
 547          * @param client
 548          *              The client sending the message
 549          * @param message
 550          *              The message
 551          */
 552         private void handleCtcp(Source client, String message) {
 553                 String[] messageWords = message.substring(1, message.length() - 1).split(" +");
 554                 String ctcpCommand = messageWords[0];
 555                 if (ctcpCommand.equalsIgnoreCase("DCC")) {
 556                         if (messageWords[1].equalsIgnoreCase("SEND")) {
 557                                 Optional<InetAddress> inetAddress = parseInetAddress(messageWords[3]);
 558                                 Optional<Integer> port = Optional.fromNullable(Ints.tryParse(messageWords[4]));
 559                                 long fileSize = Optional.fromNullable(Longs.tryParse(messageWords[5])).or(-1L);
 560                                 if (inetAddress.isPresent() && port.isPresent()) {
 561                                         eventBus.post(new DccSendReceived(this, client, messageWords[2], inetAddress.get(), port.get(), fileSize));
 562                                 } else {
 563                                         logger.warn(String.format("Received malformed DCC SEND: “%s”", message));
 564                                 }
 565                         } else if (messageWords[1].equalsIgnoreCase("ACCEPT")) {
 566                                 Optional<Integer> port = Optional.fromNullable(Ints.tryParse(messageWords[3]));
 567                                 long position = (messageWords.length > 4) ? Optional.fromNullable(Longs.tryParse(messageWords[4])).or(-1L) : -1;
 568                                 if (port.isPresent()) {
 569                                         eventBus.post(new DccAcceptReceived(this, client, messageWords[2], port.get(), position));
 570                                 } else {
 571                                         logger.warn(String.format("Received malformed DCC ACCEPT: “%s”", message));
 572                                 }
 573                         }
 574                 }
 575         }
 576
 577         /**
 578          * Returns an item from the list, or {@link Optional#absent()} if the list is
 579          * shorter than required for the given index.
 580          *
 581          * @param list
 582          *              The list to get an item from
 583          * @param index
 584          *              The index of the item
 585          * @param <T>
 586          *              The type of the list items
 587          * @return This list item wrapped in an {@link Optional}, or {@link
 588          *         Optional#absent()} if the list is not long enough
 589          */
 590         private static <T> Optional<T> getOptional(List<T> list, int index) {
 591                 if (index < list.size()) {
 592                         return Optional.fromNullable(list.get(index));
 593                 }
 594                 return Optional.absent();
 595         }
 596
 597         /**
 598          * Parses the given {@code ip} and returns an {@link InetAddress} from it.
 599          *
 600          * @param ip
 601          *              The IP to parse
 602          * @return The parsed inet address, or {@link Optional#absent()} if no inet
 603          *         address could be parsed
 604          */
 605         private Optional<InetAddress> parseInetAddress(String ip) {
 606                 Long ipNumber = Longs.tryParse(ip);
 607                 if (ipNumber == null) {
 608                         return Optional.absent();
 609                 }
 610
 611                 StringBuilder hostname = new StringBuilder(15);
 612                 hostname.append((ipNumber >>> 24) & 0xff).append('.');
 613                 hostname.append((ipNumber >>> 16) & 0xff).append('.');
 614                 hostname.append((ipNumber >>> 8) & 0xff).append('.');
 615                 hostname.append(ipNumber & 0xff);
 616                 try {
 617                         return Optional.of(InetAddress.getByName(hostname.toString()));
 618                 } catch (UnknownHostException uhe1) {
 619                         return Optional.absent();
 620                 }
 621         }
 622
 623         /** Handles input and output for the connection. */
 624         private class ConnectionHandler implements Closeable {
 625
 626                 /** The output stream of the connection. */
 627                 private final BandwidthCountingOutputStream outputStream;
 628
 629                 /** The input stream. */
 630                 private final BandwidthCountingInputStream inputStream;
 631
 632                 /** The input stream of the connection. */
 633                 private final BufferedReader inputStreamReader;
 634
 635                 /**
 636                  * Creates a new connection handler for the given input stream and output
 637                  * stream.
 638                  *
 639                  * @param inputStream
 640                  *              The input stream of the connection
 641                  * @param outputStream
 642                  *              The output stream of the connection
 643                  * @throws UnsupportedEncodingException
 644                  *              if the encoding (currently “UTF-8”) is not valid
 645                  */
 646                 private ConnectionHandler(InputStream inputStream, OutputStream outputStream) throws UnsupportedEncodingException {
 647                         this.outputStream = new BandwidthCountingOutputStream(outputStream, 5, SECONDS);
 648                         this.inputStream = new BandwidthCountingInputStream(inputStream, 5, SECONDS);
 649                         inputStreamReader = new BufferedReader(new InputStreamReader(this.inputStream, "UTF-8"));
 650                 }
 651
 652                 //
 653                 // ACTIONS
 654                 //
 655
 656                 /**
 657                  * Returns the current rate of the connection’s incoming side.
 658                  *
 659                  * @return The current input rate (in bytes per second)
 660                  */
 661                 public long getInputRate() {
 662                         return inputStream.getCurrentRate();
 663                 }
 664
 665                 /**
 666                  * Returns the current rate of the connection’s outgoing side.
 667                  *
 668                  * @return The current output rate (in bytes per second)
 669                  */
 670                 public long getOutputRate() {
 671                         return outputStream.getCurrentRate();
 672                 }
 673
 674                 /**
 675                  * Sends a command with the given parameters, skipping all {@link
 676                  * Optional#absent()} optionals.
 677                  *
 678                  * @param command
 679                  *              The command to send
 680                  * @param parameters
 681                  *              The parameters
 682                  * @throws IOException
 683                  *              if an I/O error occurs
 684                  */
 685                 public void sendCommand(String command, Optional<String>... parameters) throws IOException {
 686                         List<String> setParameters = new ArrayList<String>();
 687                         for (Optional<String> maybeSetParameter : parameters) {
 688                                 if (maybeSetParameter.isPresent()) {
 689                                         setParameters.add(maybeSetParameter.get());
 690                                 }
 691                         }
 692                         sendCommand(command, setParameters.toArray(new String[setParameters.size()]));
 693                 }
 694
 695                 /**
 696                  * Sends a command with the given parameters.
 697                  *
 698                  * @param command
 699                  *              The command to send
 700                  * @param parameters
 701                  *              The parameters of the command
 702                  * @throws IOException
 703                  *              if an I/O error occurs
 704                  * @throws IllegalArgumentException
 705                  *              if any parameter but that last contains a space character
 706                  */
 707                 public void sendCommand(String command, String... parameters) throws IOException, IllegalArgumentException {
 708                         StringBuilder commandBuilder = new StringBuilder();
 709
 710                         commandBuilder.append(command);
 711                         for (int parameterIndex = 0; parameterIndex < parameters.length; ++parameterIndex) {
 712                                 String parameter = parameters[parameterIndex];
 713                                 /* space is only allowed in the last parameter. */
 714                                 commandBuilder.append(' ');
 715                                 if (parameter.contains(" ")) {
 716                                         if (parameterIndex == (parameters.length - 1)) {
 717                                                 commandBuilder.append(':');
 718                                         } else {
 719                                                 throw new IllegalArgumentException(String.format("parameter “%s” must not contain space!", parameter));
 720                                         }
 721                                 }
 722                                 commandBuilder.append(parameter);
 723                         }
 724
 725                         logger.trace(String.format(">> %s", commandBuilder));
 726                         outputStream.write((commandBuilder.toString() + "\r\n").getBytes("UTF-8"));
 727                         outputStream.flush();
 728                 }
 729
 730                 /**
 731                  * Reads a line of reply from the connection.
 732                  *
 733                  * @return The reply
 734                  * @throws IOException
 735                  *              if an I/O error occurs
 736                  * @throws EOFException
 737                  *              if EOF was reached
 738                  */
 739                 public Reply readReply() throws IOException, EOFException {
 740                         String line = inputStreamReader.readLine();
 741                         if (line == null) {
 742                                 throw new EOFException();
 743                         }
 744
 745                         return Reply.parseLine(line);
 746                 }
 747
 748                 //
 749                 // CLOSEABLE METHODS
 750                 //
 751
 752                 @Override
 753                 public void close() throws IOException {
 754                         Closeables.close(outputStream, true);
 755                         Closeables.close(inputStreamReader, true);
 756                         Closeables.close(inputStream, true);
 757                 }
 758
 759         }
 760
 761 }