src/net/pterodactylus/jsite/core/NodeManager.java

   1 /*
   2  * jSite2 - FcpCollector.java -
   3  * Copyright © 2008 David Roden
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 package net.pterodactylus.jsite.core;
  21
  22 import java.beans.PropertyChangeEvent;
  23 import java.beans.PropertyChangeListener;
  24 import java.io.File;
  25 import java.io.FileInputStream;
  26 import java.io.FileOutputStream;
  27 import java.io.IOException;
  28 import java.io.InputStream;
  29 import java.io.OutputStream;
  30 import java.net.UnknownHostException;
  31 import java.util.ArrayList;
  32 import java.util.Collections;
  33 import java.util.HashMap;
  34 import java.util.Iterator;
  35 import java.util.List;
  36 import java.util.Map;
  37 import java.util.Properties;
  38 import java.util.logging.Level;
  39 import java.util.logging.Logger;
  40
  41 import net.pterodactylus.fcp.highlevel.HighLevelClient;
  42 import net.pterodactylus.fcp.highlevel.HighLevelClientListener;
  43 import net.pterodactylus.util.io.Closer;
  44 import net.pterodactylus.util.logging.Logging;
  45
  46 /**
  47  * TODO
  48  *
  49  * @author David ‘Bombe’ Roden &lt;bombe@freenetproject.org&gt;
  50  * @version $Id$
  51  */
  52 public class NodeManager implements Iterable<Node>, PropertyChangeListener, HighLevelClientListener {
  53
  54         /** Logger. */
  55         private static final Logger logger = Logging.getLogger(NodeManager.class.getName());
  56
  57         /** The FCP client name. */
  58         private final String clientName;
  59
  60         /** The directory for the configuration. */
  61         private final String directory;
  62
  63         /** Object used for synchronization. */
  64         private final Object syncObject = new Object();
  65
  66         /** Node listeners. */
  67         private List<NodeListener> nodeListeners = Collections.synchronizedList(new ArrayList<NodeListener>());
  68
  69         /** All nodes. */
  70         private List<Node> nodes = Collections.synchronizedList(new ArrayList<Node>());
  71
  72         /** All FCP connections. */
  73         private Map<Node, HighLevelClient> nodeClients = Collections.synchronizedMap(new HashMap<Node, HighLevelClient>());
  74
  75         /** Maps nodes to high-level clients. */
  76         private Map<HighLevelClient, Node> clientNodes = Collections.synchronizedMap(new HashMap<HighLevelClient, Node>());
  77
  78         /**
  79          * Creates a new FCP collector.
  80          *
  81          * @param clientName
  82          *            The name of the FCP client
  83          * @param directory
  84          *            The directory in which to store the nodes
  85          */
  86         public NodeManager(String clientName, String directory) {
  87                 this.clientName = clientName;
  88                 this.directory = directory;
  89         }
  90
  91         //
  92         // EVENT MANAGEMENT
  93         //
  94
  95         /**
  96          * Adds the given listener to the list of listeners.
  97          *
  98          * @param nodeListener
  99          *            The listener to add
 100          */
 101         public void addNodeListener(NodeListener nodeListener) {
 102                 nodeListeners.add(nodeListener);
 103         }
 104
 105         /**
 106          * Removes the given listener from the list of listeners.
 107          *
 108          * @param nodeListener
 109          *            The listener to remove
 110          */
 111         public void removeNodeListener(NodeListener nodeListener) {
 112                 nodeListeners.remove(nodeListener);
 113         }
 114
 115         /**
 116          * Notifies all listeners that a node was added.
 117          *
 118          * @param node
 119          *            The node that was added.
 120          */
 121         private void fireNodeAdded(Node node) {
 122                 for (NodeListener nodeListener: nodeListeners) {
 123                         nodeListener.nodeAdded(node);
 124                 }
 125         }
 126
 127         /**
 128          * Notifies all listeners that a node was removed.
 129          *
 130          * @param node
 131          *            The node that was removed
 132          */
 133         private void fireNodeRemoved(Node node) {
 134                 for (NodeListener nodeListener: nodeListeners) {
 135                         nodeListener.nodeRemoved(node);
 136                 }
 137         }
 138
 139         /**
 140          * Notifies all listeners that the given node was connected.
 141          *
 142          * @param node
 143          *            The node that is now connected
 144          */
 145         private void fireNodeConnected(Node node) {
 146                 for (NodeListener nodeListener: nodeListeners) {
 147                         nodeListener.nodeConnected(node);
 148                 }
 149         }
 150
 151         /**
 152          * Notifies all listeners that a connection to a node has failed.
 153          *
 154          * @param node
 155          *            The node that could not be connected
 156          * @param cause
 157          *            The cause of the failure
 158          */
 159         private void fireNodeConnectionFailed(Node node, Throwable cause) {
 160                 for (NodeListener nodeListener: nodeListeners) {
 161                         nodeListener.nodeConnectionFailed(node, cause);
 162                 }
 163         }
 164
 165         /**
 166          * Notifies all listeners that the given node was disconnected.
 167          *
 168          * @param node
 169          *            The node that is now disconnected
 170          * @param throwable
 171          *            The exception that caused the disconnect, or <code>null</code>
 172          *            if there was no exception
 173          */
 174         private void fireNodeDisconnected(Node node, Throwable throwable) {
 175                 for (NodeListener nodeListener: nodeListeners) {
 176                         nodeListener.nodeDisconnected(node, throwable);
 177                 }
 178         }
 179
 180         //
 181         // ACCESSORS
 182         //
 183
 184         /**
 185          * Returns the directory in which the nodes are stored.
 186          *
 187          * @return The directory the nodes are stored in
 188          */
 189         public String getDirectory() {
 190                 return directory;
 191         }
 192
 193         /**
 194          * Checks whether the given node is already connected.
 195          *
 196          * @param node
 197          *            The node to check
 198          * @return <code>true</code> if the node is already connected,
 199          *         <code>false</code> otherwise
 200          */
 201         public boolean hasNode(Node node) {
 202                 return nodes.contains(node);
 203         }
 204
 205         /**
 206          * {@inheritDoc}
 207          */
 208         public Iterator<Node> iterator() {
 209                 return nodes.iterator();
 210         }
 211
 212         //
 213         // ACTIONS
 214         //
 215
 216         /**
 217          * Loads nodes.
 218          *
 219          * @throws IOException
 220          *             if an I/O error occurs loading the nodes
 221          */
 222         public void load() throws IOException {
 223                 File directoryFile = new File(directory);
 224                 File nodeFile = new File(directoryFile, "nodes.properties");
 225                 if (!nodeFile.exists() || !nodeFile.isFile() || !nodeFile.canRead()) {
 226                         return;
 227                 }
 228                 Properties nodeProperties = new Properties();
 229                 InputStream nodeInputStream = null;
 230                 try {
 231                         nodeInputStream = new FileInputStream(nodeFile);
 232                         nodeProperties.load(nodeInputStream);
 233                 } finally {
 234                         Closer.close(nodeInputStream);
 235                 }
 236                 int nodeIndex = -1;
 237                 List<Node> loadedNodes = new ArrayList<Node>();
 238                 while (nodeProperties.containsKey("nodes." + ++nodeIndex + ".name")) {
 239                         String nodePrefix = "nodes." + nodeIndex;
 240                         String nodeName = nodeProperties.getProperty(nodePrefix + ".name");
 241                         if (!Verifier.verifyNodeName(nodeName)) {
 242                                 logger.log(Level.WARNING, "invalid node name “" + nodeName + "”, skipping…");
 243                                 continue;
 244                         }
 245                         String nodeHostname = nodeProperties.getProperty(nodePrefix + ".hostname");
 246                         if (!Verifier.verifyHostname(nodeHostname)) {
 247                                 logger.log(Level.WARNING, "invalid host name “" + nodeHostname + "”");
 248                                 /* not fatal, might be valid later on. */
 249                         }
 250                         String nodePortString = nodeProperties.getProperty(nodePrefix + ".port");
 251                         if (!Verifier.verifyPort(nodePortString)) {
 252                                 logger.log(Level.WARNING, "invalid port number “" + nodePortString + "”, skipping…");
 253                                 continue;
 254                         }
 255                         int nodePort = -1;
 256                         try {
 257                                 nodePort = Integer.valueOf(nodePortString);
 258                         } catch (NumberFormatException nfe1) {
 259                                 /* shouldn't happen, port number was checked before. */
 260                                 logger.log(Level.SEVERE, "invalid port number “" + nodePortString + "”, check failed! skipping…");
 261                                 continue;
 262                         }
 263                         Node newNode = new Node();
 264                         newNode.setName(nodeName);
 265                         newNode.setHostname(nodeHostname);
 266                         newNode.setPort(nodePort);
 267                         loadedNodes.add(newNode);
 268                 }
 269                 logger.fine("loaded " + loadedNodes.size() + " nodes from config");
 270                 synchronized (syncObject) {
 271                         nodes.clear();
 272                         for (Node node: loadedNodes) {
 273                                 addNode(node);
 274                         }
 275                 }
 276         }
 277
 278         /**
 279          * Saves all configured nodes.
 280          *
 281          * @throws IOException
 282          *             if an I/O error occurs saving the nodes
 283          */
 284         public void save() throws IOException {
 285                 File directoryFile = new File(directory);
 286                 if (!directoryFile.exists()) {
 287                         if (!directoryFile.mkdirs()) {
 288                                 throw new IOException("could not create directory: " + directory);
 289                         }
 290                 }
 291                 Properties nodeProperties = new Properties();
 292                 int nodeIndex = -1;
 293                 for (Node node: nodes) {
 294                         String nodePrefix = "nodes." + ++nodeIndex;
 295                         nodeProperties.setProperty(nodePrefix + ".name", node.getName());
 296                         nodeProperties.setProperty(nodePrefix + ".hostname", node.getHostname());
 297                         nodeProperties.setProperty(nodePrefix + ".port", String.valueOf(node.getPort()));
 298                 }
 299                 File projectFile = new File(directoryFile, "nodes.properties");
 300                 OutputStream nodeOutputStream = null;
 301                 try {
 302                         nodeOutputStream = new FileOutputStream(projectFile);
 303                         nodeProperties.store(nodeOutputStream, "jSite nodes");
 304                 } finally {
 305                         Closer.close(nodeOutputStream);
 306                 }
 307         }
 308
 309         /**
 310          * Adds the given node to this manager.
 311          *
 312          * @see #connect(Node)
 313          * @param node
 314          *            The node to connect to
 315          * @return <code>true</code> if the node was added, <code>false</code>
 316          *         if the node was not added because it was already known
 317          */
 318         public boolean addNode(Node node) {
 319                 if (nodes.contains(node)) {
 320                         logger.warning("was told to add already known node: " + node);
 321                         return false;
 322                 }
 323                 node.addPropertyChangeListener(this);
 324                 HighLevelClient highLevelClient = new HighLevelClient(clientName);
 325                 nodes.add(node);
 326                 clientNodes.put(highLevelClient, node);
 327                 nodeClients.put(node, highLevelClient);
 328                 highLevelClient.addHighLevelClientListener(this);
 329                 fireNodeAdded(node);
 330                 return true;
 331         }
 332
 333         /**
 334          * Removes the given node from the node manager, disconnecting it if it is
 335          * currently connected.
 336          *
 337          * @param node
 338          *            The node to remove
 339          */
 340         public void removeNode(Node node) {
 341                 synchronized (syncObject) {
 342                         if (!nodes.contains(node)) {
 343                                 return;
 344                         }
 345                         if (nodeClients.containsKey(node)) {
 346                                 disconnect(node);
 347                         }
 348                         node.removePropertyChangeListener(this);
 349                         fireNodeRemoved(node);
 350                 }
 351         }
 352
 353         /**
 354          * Tries to establish a connection with the given node.
 355          *
 356          * @param node
 357          *            The node to connect to
 358          */
 359         public void connect(Node node) {
 360                 HighLevelClient highLevelClient;
 361                 highLevelClient = nodeClients.get(node);
 362                 if (highLevelClient == null) {
 363                         logger.warning("was told to connect to unknown node: " + node);
 364                         return;
 365                 }
 366                 try {
 367                         highLevelClient.connect(node.getHostname(), node.getPort());
 368                 } catch (UnknownHostException uhe1) {
 369                         fireNodeConnectionFailed(node, uhe1);
 370                 } catch (IOException ioe1) {
 371                         fireNodeConnectionFailed(node, ioe1);
 372                 }
 373         }
 374
 375         /**
 376          * Disconnects the given node without removing it.
 377          *
 378          * @param node
 379          *            The node to disconnect
 380          */
 381         public void disconnect(Node node) {
 382                 synchronized (syncObject) {
 383                         if (!nodes.contains(node)) {
 384                                 return;
 385                         }
 386                         HighLevelClient highLevelClient = nodeClients.get(node);
 387                         highLevelClient.disconnect();
 388                 }
 389         }
 390
 391         /**
 392          * Returns a list of all nodes.
 393          *
 394          * @return A list of all nodes
 395          */
 396         public List<Node> getNodes() {
 397                 return Collections.unmodifiableList(nodes);
 398         }
 399
 400         /**
 401          * Returns the high-level client for a given node.
 402          *
 403          * @param node
 404          *            The node to get a high-level client for
 405          * @return The high-level client for a node, or <code>null</code> if the
 406          *         node was disconnected or removed
 407          */
 408         public HighLevelClient getHighLevelClient(Node node) {
 409                 return nodeClients.get(node);
 410         }
 411
 412         //
 413         // PRIVATE METHODS
 414         //
 415
 416         //
 417         // INTERFACE HighLevelClientListener
 418         //
 419
 420         /**
 421          * {@inheritDoc}
 422          */
 423         public void clientConnected(HighLevelClient highLevelClient) {
 424                 logger.log(Level.FINER, "clientConnected(c=" + highLevelClient + ")");
 425                 Node node = clientNodes.get(highLevelClient);
 426                 if (node == null) {
 427                         logger.log(Level.WARNING, "got event for unknown client");
 428                         return;
 429                 }
 430                 fireNodeConnected(node);
 431         }
 432
 433         /**
 434          * {@inheritDoc}
 435          */
 436         public void clientDisconnected(HighLevelClient highLevelClient, Throwable throwable) {
 437                 logger.log(Level.FINER, "clientDisconnected(c=" + highLevelClient + ",t=" + throwable + ")");
 438                 synchronized (syncObject) {
 439                         Node node = clientNodes.get(highLevelClient);
 440                         if (node == null) {
 441                                 logger.log(Level.WARNING, "got event for unknown client");
 442                                 return;
 443                         }
 444                         fireNodeDisconnected(node, throwable);
 445                 }
 446         }
 447
 448         //
 449         // INTERFACE PropertyChangeListener
 450         //
 451
 452         /**
 453          * {@inheritDoc}
 454          */
 455         public void propertyChange(PropertyChangeEvent propertyChangeEvent) {
 456                 Object eventSource = propertyChangeEvent.getSource();
 457                 if (eventSource instanceof Node) {
 458                         String propertyName = propertyChangeEvent.getPropertyName();
 459                         if ("hostname".equals(propertyName) || "port".equals(propertyName)) {
 460                                 Node node = (Node) eventSource;
 461                                 HighLevelClient highLevelClient = nodeClients.get(node);
 462                                 if (highLevelClient == null) {
 463                                         logger.log(Level.WARNING, "got property change event for unknown node: " + node);
 464                                         return;
 465                                 }
 466                                 if (highLevelClient.isConnected()) {
 467                                         highLevelClient.disconnect();
 468                                         try {
 469                                                 highLevelClient.connect(node.getHostname(), node.getPort());
 470                                         } catch (UnknownHostException uhe1) {
 471                                                 fireNodeConnectionFailed(node, uhe1);
 472                                         } catch (IOException ioe1) {
 473                                                 fireNodeConnectionFailed(node, ioe1);
 474                                         }
 475                                 }
 476                         }
 477                 }
 478         }
 479
 480 }