src/main/java/net/pterodactylus/sone/freenet/wot/IdentityManager.java

   1 /*
   2  * Sone - IdentityManager.java - Copyright © 2010–2012 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.sone.freenet.wot;
  19
  20 import java.util.Collections;
  21 import java.util.HashMap;
  22 import java.util.HashSet;
  23 import java.util.Map;
  24 import java.util.Map.Entry;
  25 import java.util.Set;
  26 import java.util.logging.Level;
  27 import java.util.logging.Logger;
  28
  29 import net.pterodactylus.sone.freenet.plugin.PluginException;
  30 import net.pterodactylus.util.logging.Logging;
  31 import net.pterodactylus.util.service.AbstractService;
  32
  33 /**
  34  * The identity manager takes care of loading and storing identities, their
  35  * contexts, and properties. It does so in a way that does not expose errors via
  36  * exceptions but it only logs them and tries to return sensible defaults.
  37  * <p>
  38  * It is also responsible for polling identities from the Web of Trust plugin
  39  * and notifying registered {@link IdentityListener}s when {@link Identity}s and
  40  * {@link OwnIdentity}s are discovered or disappearing.
  41  *
  42  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  43  */
  44 public class IdentityManager extends AbstractService {
  45
  46         /** Object used for synchronization. */
  47         @SuppressWarnings("hiding")
  48         private final Object syncObject = new Object() {
  49                 /* inner class for better lock names. */
  50         };
  51
  52         /** The logger. */
  53         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  54
  55         /** The event manager. */
  56         private final IdentityListenerManager identityListenerManager = new IdentityListenerManager();
  57
  58         /** The Web of Trust connector. */
  59         private final WebOfTrustConnector webOfTrustConnector;
  60
  61         /** The context to filter for. */
  62         private final String context;
  63
  64         /** The currently known own identities. */
  65         /* synchronize access on syncObject. */
  66         private final Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
  67
  68         /** The last time all identities were loaded. */
  69         private volatile long identitiesLastLoaded;
  70
  71         /**
  72          * Creates a new identity manager.
  73          *
  74          * @param webOfTrustConnector
  75          *            The Web of Trust connector
  76          * @param context
  77          *            The context to focus on (may be {@code null} to ignore
  78          *            contexts)
  79          */
  80         public IdentityManager(WebOfTrustConnector webOfTrustConnector, String context) {
  81                 super("Sone Identity Manager", false);
  82                 this.webOfTrustConnector = webOfTrustConnector;
  83                 this.context = context;
  84         }
  85
  86         //
  87         // LISTENER MANAGEMENT
  88         //
  89
  90         /**
  91          * Adds a listener for identity events.
  92          *
  93          * @param identityListener
  94          *            The listener to add
  95          */
  96         public void addIdentityListener(IdentityListener identityListener) {
  97                 identityListenerManager.addListener(identityListener);
  98         }
  99
 100         /**
 101          * Removes a listener for identity events.
 102          *
 103          * @param identityListener
 104          *            The listener to remove
 105          */
 106         public void removeIdentityListener(IdentityListener identityListener) {
 107                 identityListenerManager.removeListener(identityListener);
 108         }
 109
 110         //
 111         // ACCESSORS
 112         //
 113
 114         /**
 115          * Returns the last time all identities were loaded.
 116          *
 117          * @return The last time all identities were loaded (in milliseconds since
 118          *         Jan 1, 1970 UTC)
 119          */
 120         public long getIdentitiesLastLoaded() {
 121                 return identitiesLastLoaded;
 122         }
 123
 124         /**
 125          * Returns whether the Web of Trust plugin could be reached during the last
 126          * try.
 127          *
 128          * @return {@code true} if the Web of Trust plugin is connected,
 129          *         {@code false} otherwise
 130          */
 131         public boolean isConnected() {
 132                 try {
 133                         webOfTrustConnector.ping();
 134                         return true;
 135                 } catch (PluginException pe1) {
 136                         /* not connected, ignore. */
 137                         return false;
 138                 }
 139         }
 140
 141         /**
 142          * Returns the own identity with the given ID.
 143          *
 144          * @param id
 145          *            The ID of the own identity
 146          * @return The own identity, or {@code null} if there is no such identity
 147          */
 148         public OwnIdentity getOwnIdentity(String id) {
 149                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 150                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 151                         if (ownIdentity.getId().equals(id)) {
 152                                 return new DefaultOwnIdentity(ownIdentity);
 153                         }
 154                 }
 155                 return null;
 156         }
 157
 158         /**
 159          * Returns all own identities.
 160          *
 161          * @return All own identities
 162          */
 163         public Set<OwnIdentity> getAllOwnIdentities() {
 164                 return new HashSet<OwnIdentity>(currentOwnIdentities.values());
 165         }
 166
 167         //
 168         // SERVICE METHODS
 169         //
 170
 171         /**
 172          * {@inheritDoc}
 173          */
 174         @Override
 175         protected void serviceRun() {
 176                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 177                 while (!shouldStop()) {
 178                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 179                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 180
 181                         Set<OwnIdentity> ownIdentities = null;
 182                         boolean identitiesLoaded = false;
 183                         try {
 184                                 /* get all identities with the wanted context from WoT. */
 185                                 ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 186
 187                                 /* load trusted identities. */
 188                                 for (OwnIdentity ownIdentity : ownIdentities) {
 189                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 190                                                 continue;
 191                                         }
 192                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 193
 194                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 195                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 196                                         currentIdentities.put(ownIdentity, identities);
 197                                         for (Identity identity : trustedIdentities) {
 198                                                 identities.put(identity.getId(), identity);
 199                                         }
 200                                 }
 201                                 identitiesLoaded = true;
 202                                 identitiesLastLoaded = System.currentTimeMillis();
 203                         } catch (WebOfTrustException wote1) {
 204                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 205                         }
 206
 207                         if (identitiesLoaded) {
 208
 209                                 /* check for changes. */
 210                                 checkOwnIdentities(currentOwnIdentities);
 211
 212                                 /* now check for changes in remote identities. */
 213                                 for (OwnIdentity ownIdentity : currentOwnIdentities.values()) {
 214
 215                                         /* find new identities. */
 216                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 217                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 218                                                         identityListenerManager.fireIdentityAdded(ownIdentity, currentIdentity);
 219                                                 }
 220                                         }
 221
 222                                         /* find removed identities. */
 223                                         if (oldIdentities.containsKey(ownIdentity)) {
 224                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 225                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 226                                                                 identityListenerManager.fireIdentityRemoved(ownIdentity, oldIdentity);
 227                                                         }
 228                                                 }
 229
 230                                                 /* check for changes in the contexts. */
 231                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 232                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 233                                                                 continue;
 234                                                         }
 235                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 236                                                         Set<String> oldContexts = oldIdentity.getContexts();
 237                                                         Set<String> newContexts = newIdentity.getContexts();
 238                                                         if (oldContexts.size() != newContexts.size()) {
 239                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 240                                                                 continue;
 241                                                         }
 242                                                         for (String oldContext : oldContexts) {
 243                                                                 if (!newContexts.contains(oldContext)) {
 244                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 245                                                                         break;
 246                                                                 }
 247                                                         }
 248                                                 }
 249
 250                                                 /* check for changes in the properties. */
 251                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 252                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 253                                                                 continue;
 254                                                         }
 255                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 256                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 257                                                         Map<String, String> newProperties = newIdentity.getProperties();
 258                                                         if (oldProperties.size() != newProperties.size()) {
 259                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 260                                                                 continue;
 261                                                         }
 262                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 263                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 264                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 265                                                                         break;
 266                                                                 }
 267                                                         }
 268                                                 }
 269                                         }
 270                                 }
 271
 272                                 /* remember the current set of identities. */
 273                                 oldIdentities = currentIdentities;
 274                         }
 275
 276                         /* wait a minute before checking again. */
 277                         sleep(60 * 1000);
 278                 }
 279         }
 280
 281         //
 282         // PRIVATE METHODS
 283         //
 284
 285         /**
 286          * Checks the given new list of own identities for added or removed own
 287          * identities, as compared to {@link #currentOwnIdentities}.
 288          *
 289          * @param newOwnIdentities
 290          *            The new own identities
 291          */
 292         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 293                 synchronized (syncObject) {
 294
 295                         /* find removed own identities: */
 296                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 297                                 OwnIdentity newOwnIdentity = newOwnIdentities.get(oldOwnIdentity.getId());
 298                                 if ((newOwnIdentity == null) || ((context != null) && oldOwnIdentity.hasContext(context) && !newOwnIdentity.hasContext(context))) {
 299                                         identityListenerManager.fireOwnIdentityRemoved(new DefaultOwnIdentity(oldOwnIdentity));
 300                                 }
 301                         }
 302
 303                         /* find added own identities. */
 304                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 305                                 OwnIdentity oldOwnIdentity = currentOwnIdentities.get(currentOwnIdentity.getId());
 306                                 if (((oldOwnIdentity == null) && ((context == null) || currentOwnIdentity.hasContext(context))) || ((oldOwnIdentity != null) && (context != null) && (!oldOwnIdentity.hasContext(context) && currentOwnIdentity.hasContext(context)))) {
 307                                         identityListenerManager.fireOwnIdentityAdded(new DefaultOwnIdentity(currentOwnIdentity));
 308                                 }
 309                         }
 310
 311                         currentOwnIdentities.clear();
 312                         currentOwnIdentities.putAll(newOwnIdentities);
 313                 }
 314         }
 315
 316 }