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.Arrays.asList;
  22 import static java.util.concurrent.TimeUnit.SECONDS;
  23
  24 import java.io.BufferedReader;
  25 import java.io.Closeable;
  26 import java.io.EOFException;
  27 import java.io.IOException;
  28 import java.io.InputStream;
  29 import java.io.InputStreamReader;
  30 import java.io.OutputStream;
  31 import java.io.UnsupportedEncodingException;
  32 import java.net.InetAddress;
  33 import java.net.Socket;
  34 import java.net.UnknownHostException;
  35 import java.util.ArrayList;
  36 import java.util.List;
  37 import java.util.Map;
  38 import java.util.Set;
  39 import java.util.concurrent.TimeUnit;
  40 import java.util.concurrent.atomic.AtomicBoolean;
  41
  42 import javax.net.SocketFactory;
  43
  44 import net.pterodactylus.irc.connection.ChannelNotJoinedHandler;
  45 import net.pterodactylus.irc.connection.ConnectionEstablishHandler;
  46 import net.pterodactylus.irc.connection.Handler;
  47 import net.pterodactylus.irc.event.ChannelJoined;
  48 import net.pterodactylus.irc.event.ChannelLeft;
  49 import net.pterodactylus.irc.event.ChannelMessageReceived;
  50 import net.pterodactylus.irc.event.ChannelNicknames;
  51 import net.pterodactylus.irc.event.ChannelNotJoined;
  52 import net.pterodactylus.irc.event.ChannelNotJoined.Reason;
  53 import net.pterodactylus.irc.event.ChannelNoticeReceived;
  54 import net.pterodactylus.irc.event.ChannelTopic;
  55 import net.pterodactylus.irc.event.ClientQuit;
  56 import net.pterodactylus.irc.event.ConnectionClosed;
  57 import net.pterodactylus.irc.event.ConnectionEstablished;
  58 import net.pterodactylus.irc.event.ConnectionFailed;
  59 import net.pterodactylus.irc.event.DccAcceptReceived;
  60 import net.pterodactylus.irc.event.DccSendReceived;
  61 import net.pterodactylus.irc.event.KickedFromChannel;
  62 import net.pterodactylus.irc.event.MotdReceived;
  63 import net.pterodactylus.irc.event.NicknameChanged;
  64 import net.pterodactylus.irc.event.NicknameInUseReceived;
  65 import net.pterodactylus.irc.event.NoNicknameGivenReceived;
  66 import net.pterodactylus.irc.event.PrivateMessageReceived;
  67 import net.pterodactylus.irc.event.PrivateNoticeReceived;
  68 import net.pterodactylus.irc.event.ReplyReceived;
  69 import net.pterodactylus.irc.event.UnknownReplyReceived;
  70 import net.pterodactylus.irc.util.RandomNickname;
  71 import net.pterodactylus.xdcc.util.io.BandwidthCountingInputStream;
  72 import net.pterodactylus.xdcc.util.io.BandwidthCountingOutputStream;
  73
  74 import com.google.common.base.Optional;
  75 import com.google.common.collect.Maps;
  76 import com.google.common.collect.Sets;
  77 import com.google.common.eventbus.EventBus;
  78 import com.google.common.eventbus.Subscribe;
  79 import com.google.common.io.Closeables;
  80 import com.google.common.primitives.Ints;
  81 import com.google.common.primitives.Longs;
  82 import com.google.common.util.concurrent.AbstractExecutionThreadService;
  83 import com.google.common.util.concurrent.Service;
  84 import org.apache.log4j.Logger;
  85
  86 /**
  87  * A connection to an IRC server.
  88  *
  89  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  90  */
  91 public class Connection extends AbstractExecutionThreadService implements Service {
  92
  93         /* The logger. */
  94         private static final Logger logger = Logger.getLogger(Connection.class.getName());
  95
  96         /** The event bus. */
  97         private final EventBus eventBus;
  98
  99         /** The socket factory. */
 100         private final SocketFactory socketFactory;
 101
 102         /** The hostname to connect to. */
 103         private final String hostname;
 104
 105         /** The port to connect to. */
 106         private final int port;
 107
 108         /** The nickname chooser. */
 109         private NicknameChooser nicknameChooser = new NicknameChooser() {
 110
 111                 @Override
 112                 public String getNickname() {
 113                         return RandomNickname.get();
 114                 }
 115         };
 116
 117         /** The nickname. */
 118         private String nickname = null;
 119
 120         /** The username. */
 121         private Optional<String> username = Optional.absent();
 122
 123         /** The real name. */
 124         private Optional<String> realName = Optional.absent();
 125
 126         /** The optional password for the connection. */
 127         private Optional<String> password = Optional.absent();
 128
 129         /** The connection handler. */
 130         private ConnectionHandler connectionHandler;
 131
 132         /** Whether the connection has already been established. */
 133         private final AtomicBoolean established = new AtomicBoolean();
 134
 135         /**
 136          * Creates a new connection.
 137          *
 138          * @param eventBus
 139          *              The event bus
 140          * @param socketFactory
 141          *              The socket factory
 142          * @param hostname
 143          *              The hostname of the IRC server
 144          * @param port
 145          *              The port number of the IRC server
 146          */
 147         public Connection(EventBus eventBus, SocketFactory socketFactory, String hostname, int port) {
 148                 this.eventBus = eventBus;
 149                 this.socketFactory = socketFactory;
 150                 this.hostname = hostname;
 151                 this.port = port;
 152         }
 153
 154         //
 155         // ACCESSORS
 156         //
 157
 158         /**
 159          * Returns the hostname of the remote end of the connection.
 160          *
 161          * @return The remote’s hostname
 162          */
 163         public String hostname() {
 164                 return hostname;
 165         }
 166
 167         /**
 168          * Returns the port number of the remote end of the connection.
 169          *
 170          * @return The remote’s port number
 171          */
 172         public int port() {
 173                 return port;
 174         }
 175
 176         /**
 177          * Returns whether this connection has already been established.
 178          *
 179          * @return {@code true} as long as this connection is established, {@code
 180          *         false} otherwise
 181          */
 182         public boolean established() {
 183                 return established.get();
 184         }
 185
 186         /**
 187          * Returns the nickname that is currently in use by this connection. The
 188          * nickname is only available once the connection has been {@link #start()}ed.
 189          *
 190          * @return The current nickname
 191          */
 192         public String nickname() {
 193                 return nickname;
 194         }
 195
 196         //
 197         // MUTATORS
 198         //
 199
 200         /**
 201          * Sets the nickname chooser. The nickname chooser is only used during the
 202          * creation of the connection.
 203          *
 204          * @param nicknameChooser
 205          *              The nickname chooser
 206          * @return This connection
 207          */
 208         public Connection nicknameChooser(NicknameChooser nicknameChooser) {
 209                 this.nicknameChooser = nicknameChooser;
 210                 return this;
 211         }
 212
 213         /**
 214          * Sets the username to use.
 215          *
 216          * @param username
 217          *              The username to use
 218          * @return This connection
 219          */
 220         public Connection username(String username) {
 221                 this.username = Optional.fromNullable(username);
 222                 return this;
 223         }
 224
 225         /**
 226          * Sets the real name to use.
 227          *
 228          * @param realName
 229          *              The real name to use
 230          * @return This connection
 231          */
 232         public Connection realName(String realName) {
 233                 this.realName = Optional.fromNullable(realName);
 234                 return this;
 235         }
 236
 237         /**
 238          * Sets the optional password for the connection.
 239          *
 240          * @param password
 241          *              The password for the connection
 242          * @return This connection
 243          */
 244         public Connection password(String password) {
 245                 this.password = Optional.fromNullable(password);
 246                 return this;
 247         }
 248
 249         //
 250         // ACTIONS
 251         //
 252
 253         /**
 254          * Returns the current rate of the connection’s incoming side.
 255          *
 256          * @return The current input rate (in bytes per second)
 257          */
 258         public long getInputRate() {
 259                 return (connectionHandler != null) ? connectionHandler.getInputRate() : 0;
 260         }
 261
 262         /**
 263          * Returns the current rate of the connection’s outgoing side.
 264          *
 265          * @return The current output rate (in bytes per second)
 266          */
 267         public long getOutputRate() {
 268                 return (connectionHandler != null) ? connectionHandler.getOutputRate() : 0;
 269         }
 270
 271         /**
 272          * Checks whether the given source is the client represented by this
 273          * connection.
 274          *
 275          * @param source
 276          *              The source to check
 277          * @return {@code true} if this connection represents the given source, {@code
 278          *         false} otherwise
 279          */
 280         public boolean isSource(Source source) {
 281                 return source.nick().isPresent() && source.nick().get().equals(nickname);
 282         }
 283
 284         /**
 285          * Joins the given channel.
 286          *
 287          * @param channel
 288          *              The channel to join
 289          * @throws IOException
 290          *              if an I/O error occurs
 291          */
 292         public void joinChannel(final String channel) throws IOException {
 293                 connectionHandler.sendCommand("JOIN", channel);
 294         }
 295
 296         /**
 297          * Sends a message to the given recipient, which may be a channel or another
 298          * nickname.
 299          *
 300          * @param recipient
 301          *              The recipient of the message
 302          * @param message
 303          *              The message
 304          * @throws IOException
 305          *              if an I/O error occurs
 306          */
 307         public void sendMessage(String recipient, String message) throws IOException {
 308                 connectionHandler.sendCommand("PRIVMSG", recipient, message);
 309         }
 310
 311         /**
 312          * Sends a DCC RESUME request to the given recipient.
 313          *
 314          * @param recipient
 315          *              The recipient of the request
 316          * @param filename
 317          *              The name of the file to resume
 318          * @param port
 319          *              The port number from the original DCC SEND request
 320          * @param position
 321          *              The position at which to resume the transfer
 322          * @throws IOException
 323          *              if an I/O error occurs
 324          */
 325         public void sendDccResume(String recipient, String filename, int port, long position) throws IOException {
 326                 connectionHandler.sendCommand("PRIVMSG", recipient, String.format("\u0001DCC RESUME %s %d %d\u0001", filename, port, position));
 327         }
 328
 329         /**
 330          * Closes this connection.
 331          *
 332          * @throws IOException
 333          *              if an I/O error occurs
 334          */
 335         public void close() throws IOException {
 336                 if (connectionHandler != null) {
 337                         connectionHandler.close();
 338                 }
 339         }
 340
 341         //
 342         // ABSTRACTEXECUTIONTHREADSERVICE METHODS
 343         //
 344
 345         @Override
 346         protected void startUp() throws IllegalStateException {
 347                 checkState(username.isPresent(), "username must be set");
 348                 checkState(realName.isPresent(), "realName must be set");
 349         }
 350
 351         @Override
 352         protected void run() {
 353
 354                 /* connect to remote socket. */
 355                 try {
 356                         Socket socket = socketFactory.createSocket(hostname, port);
 357                         socket.setSoTimeout((int) TimeUnit.MINUTES.toMillis(3));
 358                         connectionHandler = new ConnectionHandler(socket.getInputStream(), socket.getOutputStream());
 359
 360                         /* register connection. */
 361                         if (password.isPresent()) {
 362                                 connectionHandler.sendCommand("PASSWORD", password.get());
 363                         }
 364                         connectionHandler.sendCommand("USER", username.get(), "8", "*", realName.get());
 365                         nickname = nicknameChooser.getNickname();
 366                         connectionHandler.sendCommand("NICK", nickname);
 367
 368                 } catch (IOException ioe1) {
 369                         eventBus.post(new ConnectionFailed(this, ioe1));
 370                         return;
 371                 }
 372
 373                 eventBus.register(this);
 374                 /* now read replies and react. */
 375                 try {
 376                         /* some status variables. */
 377                         int oldConnectionStatus = 0;
 378                         int connectionStatus = 0;
 379                         boolean connected = true;
 380                         StringBuilder motd = new StringBuilder();
 381                         Set<Nickname> nicks = Sets.newHashSet();
 382
 383                         /* server modes. */
 384                         Map<String, String> nickPrefixes = Maps.newHashMap();
 385                         Set<Character> channelTypes = Sets.newHashSet();
 386
 387                         List<Handler> handlers = asList(
 388                                         new ConnectionEstablishHandler(eventBus, this),
 389                                         new ChannelNotJoinedHandler(eventBus, this)
 390                         );
 391
 392                         while (connected) {
 393                                 Reply reply = connectionHandler.readReply();
 394                                 eventBus.post(new ReplyReceived(this, reply));
 395                                 logger.trace(String.format("<< %s", reply));
 396                                 String command = reply.command();
 397                                 List<String> parameters = reply.parameters();
 398
 399                                 for (Handler handler : handlers) {
 400                                         if (handler.willHandle(reply)) {
 401                                                 handler.handleReply(reply);
 402                                                 break;
 403                                         }
 404                                 }
 405
 406                                 /* most common events. */
 407                                 if (command.equalsIgnoreCase("PRIVMSG")) {
 408                                         String recipient = parameters.get(0);
 409                                         String message = parameters.get(1);
 410                                         if (message.startsWith("\u0001") && message.endsWith("\u0001")) {
 411                                                 /* CTCP! */
 412                                                 handleCtcp(reply.source().get(), message);
 413                                         } else if (!channelTypes.contains(recipient.charAt(0))) {
 414                                                 eventBus.post(new PrivateMessageReceived(this, reply.source().get(), message));
 415                                         } else {
 416                                                 eventBus.post(new ChannelMessageReceived(this, recipient, reply.source().get(), message));
 417                                         }
 418
 419                                 } else if (command.equalsIgnoreCase("NOTICE")) {
 420                                         String recipient = parameters.get(0);
 421                                         String message = parameters.get(1);
 422                                         if (message.startsWith("\u0001") && message.endsWith("\u0001")) {
 423                                                 /* CTCP! */
 424                                                 handleCtcp(reply.source().get(), message);
 425                                         } else if (!channelTypes.contains(recipient.charAt(0))) {
 426                                                 eventBus.post(new PrivateNoticeReceived(this, reply));
 427                                         } else {
 428                                                 eventBus.post(new ChannelNoticeReceived(this, reply.source().get(), recipient, message));
 429                                         }
 430
 431                                 /* 43x replies are for nick change errors. */
 432                                 } else if (command.equals("431")) {
 433                                         eventBus.post(new NoNicknameGivenReceived(this, reply));
 434                                 } else if (command.equals("433")) {
 435                                         if (connectionStatus == 0) {
 436                                                 nickname = nicknameChooser.getNickname();
 437                                                 connectionHandler.sendCommand("NICK", nickname);
 438                                         } else {
 439                                                 eventBus.post(new NicknameInUseReceived(this, reply));
 440                                         }
 441
 442                                 /* client stuff. */
 443                                 } else if (command.equalsIgnoreCase("NICK")) {
 444                                         eventBus.post(new NicknameChanged(this, reply.source().get(), parameters.get(0)));
 445
 446                                 /* channel stuff. */
 447                                 } else if (command.equalsIgnoreCase("JOIN")) {
 448                                         eventBus.post(new ChannelJoined(this, parameters.get(0), reply.source().get()));
 449                                 } else if (command.equals("331")) {
 450                                         /* no topic is set. */
 451                                 } else if (command.equals("332")) {
 452                                         eventBus.post(new ChannelTopic(this, parameters.get(1), parameters.get(2)));
 453                                 } else if (command.equals("353")) {
 454                                         for (String nickname : parameters.get(3).split(" ")) {
 455                                                 if (nickPrefixes.containsKey(nickname.substring(0, 1))) {
 456                                                         nicks.add(new Nickname(nickname.substring(1), nickname.substring(0, 1)));
 457                                                 } else {
 458                                                         nicks.add(new Nickname(nickname, ""));
 459                                                 }
 460                                         }
 461                                 } else if (command.equals("366")) {
 462                                         eventBus.post(new ChannelNicknames(this, parameters.get(1), nicks));
 463                                         nicks.clear();
 464                                 } else if (command.equalsIgnoreCase("PART")) {
 465                                         eventBus.post(new ChannelLeft(this, parameters.get(0), reply.source().get(), getOptional(parameters, 1)));
 466                                 } else if (command.equalsIgnoreCase("QUIT")) {
 467                                         eventBus.post(new ClientQuit(this, reply.source().get(), parameters.get(0)));
 468
 469                                 /* basic connection housekeeping. */
 470                                 } else if (command.equalsIgnoreCase("PING")) {
 471                                         connectionHandler.sendCommand("PONG", getOptional(parameters, 0), getOptional(parameters, 1));
 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                         eventBus.post(new ConnectionClosed(this));
 515                 } catch (IOException ioe1) {
 516                         logger.warn("I/O error", ioe1);
 517                         eventBus.post(new ConnectionClosed(this, ioe1));
 518                 } catch (RuntimeException re1) {
 519                         logger.error("Runtime error", re1);
 520                         eventBus.post(new ConnectionClosed(this, re1));
 521                 } finally {
 522                         established.set(false);
 523                         eventBus.unregister(this);
 524                         logger.info("Closing Connection.");
 525                         try {
 526                                 Closeables.close(connectionHandler, true);
 527                         } catch (IOException ioe1) {
 528                                 /* will not be thrown. */
 529                         }
 530                 }
 531
 532         }
 533
 534         @Subscribe
 535         public void connectionEstablished(ConnectionEstablished connectionEstablished) {
 536                 if (connectionEstablished.connection() == this) {
 537                         established.set(true);
 538                 }
 539         }
 540
 541         //
 542         // PRIVATE METHODS
 543         //
 544
 545         /**
 546          * Handles a CTCP message.
 547          *
 548          * @param client
 549          *              The client sending the message
 550          * @param message
 551          *              The message
 552          */
 553         private void handleCtcp(Source client, String message) {
 554                 String[] messageWords = message.substring(1, message.length() - 1).split(" +");
 555                 String ctcpCommand = messageWords[0];
 556                 if (ctcpCommand.equalsIgnoreCase("DCC")) {
 557                         if (messageWords[1].equalsIgnoreCase("SEND")) {
 558                                 Optional<InetAddress> inetAddress = parseInetAddress(messageWords[3]);
 559                                 Optional<Integer> port = Optional.fromNullable(Ints.tryParse(messageWords[4]));
 560                                 long fileSize = Optional.fromNullable(Longs.tryParse(messageWords[5])).or(-1L);
 561                                 if (inetAddress.isPresent() && port.isPresent()) {
 562                                         eventBus.post(new DccSendReceived(this, client, messageWords[2], inetAddress.get(), port.get(), fileSize));
 563                                 } else {
 564                                         logger.warn(String.format("Received malformed DCC SEND: “%s”", message));
 565                                 }
 566                         } else if (messageWords[1].equalsIgnoreCase("ACCEPT")) {
 567                                 Optional<Integer> port = Optional.fromNullable(Ints.tryParse(messageWords[3]));
 568                                 long position = (messageWords.length > 4) ? Optional.fromNullable(Longs.tryParse(messageWords[4])).or(-1L) : -1;
 569                                 if (port.isPresent()) {
 570                                         eventBus.post(new DccAcceptReceived(this, client, messageWords[2], port.get(), position));
 571                                 } else {
 572                                         logger.warn(String.format("Received malformed DCC ACCEPT: “%s”", message));
 573                                 }
 574                         }
 575                 }
 576         }
 577
 578         /**
 579          * Returns an item from the list, or {@link Optional#absent()} if the list is
 580          * shorter than required for the given index.
 581          *
 582          * @param list
 583          *              The list to get an item from
 584          * @param index
 585          *              The index of the item
 586          * @param <T>
 587          *              The type of the list items
 588          * @return This list item wrapped in an {@link Optional}, or {@link
 589          *         Optional#absent()} if the list is not long enough
 590          */
 591         private static <T> Optional<T> getOptional(List<T> list, int index) {
 592                 if (index < list.size()) {
 593                         return Optional.fromNullable(list.get(index));
 594                 }
 595                 return Optional.absent();
 596         }
 597
 598         /**
 599          * Parses the given {@code ip} and returns an {@link InetAddress} from it.
 600          *
 601          * @param ip
 602          *              The IP to parse
 603          * @return The parsed inet address, or {@link Optional#absent()} if no inet
 604          *         address could be parsed
 605          */
 606         private Optional<InetAddress> parseInetAddress(String ip) {
 607                 Long ipNumber = Longs.tryParse(ip);
 608                 if (ipNumber == null) {
 609                         return Optional.absent();
 610                 }
 611
 612                 StringBuilder hostname = new StringBuilder(15);
 613                 hostname.append((ipNumber >>> 24) & 0xff).append('.');
 614                 hostname.append((ipNumber >>> 16) & 0xff).append('.');
 615                 hostname.append((ipNumber >>> 8) & 0xff).append('.');
 616                 hostname.append(ipNumber & 0xff);
 617                 try {
 618                         return Optional.of(InetAddress.getByName(hostname.toString()));
 619                 } catch (UnknownHostException uhe1) {
 620                         return Optional.absent();
 621                 }
 622         }
 623
 624         /** Handles input and output for the connection. */
 625         private class ConnectionHandler implements Closeable {
 626
 627                 /** The output stream of the connection. */
 628                 private final BandwidthCountingOutputStream outputStream;
 629
 630                 /** The input stream. */
 631                 private final BandwidthCountingInputStream inputStream;
 632
 633                 /** The input stream of the connection. */
 634                 private final BufferedReader inputStreamReader;
 635
 636                 /**
 637                  * Creates a new connection handler for the given input stream and output
 638                  * stream.
 639                  *
 640                  * @param inputStream
 641                  *              The input stream of the connection
 642                  * @param outputStream
 643                  *              The output stream of the connection
 644                  * @throws UnsupportedEncodingException
 645                  *              if the encoding (currently “UTF-8”) is not valid
 646                  */
 647                 private ConnectionHandler(InputStream inputStream, OutputStream outputStream) throws UnsupportedEncodingException {
 648                         this.outputStream = new BandwidthCountingOutputStream(outputStream, 5, SECONDS);
 649                         this.inputStream = new BandwidthCountingInputStream(inputStream, 5, SECONDS);
 650                         inputStreamReader = new BufferedReader(new InputStreamReader(this.inputStream, "UTF-8"));
 651                 }
 652
 653                 //
 654                 // ACTIONS
 655                 //
 656
 657                 /**
 658                  * Returns the current rate of the connection’s incoming side.
 659                  *
 660                  * @return The current input rate (in bytes per second)
 661                  */
 662                 public long getInputRate() {
 663                         return inputStream.getCurrentRate();
 664                 }
 665
 666                 /**
 667                  * Returns the current rate of the connection’s outgoing side.
 668                  *
 669                  * @return The current output rate (in bytes per second)
 670                  */
 671                 public long getOutputRate() {
 672                         return outputStream.getCurrentRate();
 673                 }
 674
 675                 /**
 676                  * Sends a command with the given parameters, skipping all {@link
 677                  * Optional#absent()} optionals.
 678                  *
 679                  * @param command
 680                  *              The command to send
 681                  * @param parameters
 682                  *              The parameters
 683                  * @throws IOException
 684                  *              if an I/O error occurs
 685                  */
 686                 public void sendCommand(String command, Optional<String>... parameters) throws IOException {
 687                         List<String> setParameters = new ArrayList<String>();
 688                         for (Optional<String> maybeSetParameter : parameters) {
 689                                 if (maybeSetParameter.isPresent()) {
 690                                         setParameters.add(maybeSetParameter.get());
 691                                 }
 692                         }
 693                         sendCommand(command, setParameters.toArray(new String[setParameters.size()]));
 694                 }
 695
 696                 /**
 697                  * Sends a command with the given parameters.
 698                  *
 699                  * @param command
 700                  *              The command to send
 701                  * @param parameters
 702                  *              The parameters of the command
 703                  * @throws IOException
 704                  *              if an I/O error occurs
 705                  * @throws IllegalArgumentException
 706                  *              if any parameter but that last contains a space character
 707                  */
 708                 public void sendCommand(String command, String... parameters) throws IOException, IllegalArgumentException {
 709                         StringBuilder commandBuilder = new StringBuilder();
 710
 711                         commandBuilder.append(command);
 712                         for (int parameterIndex = 0; parameterIndex < parameters.length; ++parameterIndex) {
 713                                 String parameter = parameters[parameterIndex];
 714                                 /* space is only allowed in the last parameter. */
 715                                 commandBuilder.append(' ');
 716                                 if (parameter.contains(" ")) {
 717                                         if (parameterIndex == (parameters.length - 1)) {
 718                                                 commandBuilder.append(':');
 719                                         } else {
 720                                                 throw new IllegalArgumentException(String.format("parameter “%s” must not contain space!", parameter));
 721                                         }
 722                                 }
 723                                 commandBuilder.append(parameter);
 724                         }
 725
 726                         logger.trace(String.format(">> %s", commandBuilder));
 727                         outputStream.write((commandBuilder.toString() + "\r\n").getBytes("UTF-8"));
 728                         outputStream.flush();
 729                 }
 730
 731                 /**
 732                  * Reads a line of reply from the connection.
 733                  *
 734                  * @return The reply
 735                  * @throws IOException
 736                  *              if an I/O error occurs
 737                  * @throws EOFException
 738                  *              if EOF was reached
 739                  */
 740                 public Reply readReply() throws IOException, EOFException {
 741                         String line = inputStreamReader.readLine();
 742                         if (line == null) {
 743                                 throw new EOFException();
 744                         }
 745
 746                         return Reply.parseLine(line);
 747                 }
 748
 749                 //
 750                 // CLOSEABLE METHODS
 751                 //
 752
 753                 @Override
 754                 public void close() throws IOException {
 755                         Closeables.close(outputStream, true);
 756                         Closeables.close(inputStreamReader, true);
 757                         Closeables.close(inputStream, true);
 758                 }
 759
 760         }
 761
 762 }