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 Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
  67
  68         /**
  69          * Creates a new identity manager.
  70          *
  71          * @param webOfTrustConnector
  72          *            The Web of Trust connector
  73          * @param context
  74          *            The context to focus on (may be {@code null} to ignore
  75          *            contexts)
  76          */
  77         public IdentityManager(WebOfTrustConnector webOfTrustConnector, String context) {
  78                 super("Sone Identity Manager", false);
  79                 this.webOfTrustConnector = webOfTrustConnector;
  80                 this.context = context;
  81         }
  82
  83         //
  84         // LISTENER MANAGEMENT
  85         //
  86
  87         /**
  88          * Adds a listener for identity events.
  89          *
  90          * @param identityListener
  91          *            The listener to add
  92          */
  93         public void addIdentityListener(IdentityListener identityListener) {
  94                 identityListenerManager.addListener(identityListener);
  95         }
  96
  97         /**
  98          * Removes a listener for identity events.
  99          *
 100          * @param identityListener
 101          *            The listener to remove
 102          */
 103         public void removeIdentityListener(IdentityListener identityListener) {
 104                 identityListenerManager.removeListener(identityListener);
 105         }
 106
 107         //
 108         // ACCESSORS
 109         //
 110
 111         /**
 112          * Returns whether the Web of Trust plugin could be reached during the last
 113          * try.
 114          *
 115          * @return {@code true} if the Web of Trust plugin is connected,
 116          *         {@code false} otherwise
 117          */
 118         public boolean isConnected() {
 119                 try {
 120                         webOfTrustConnector.ping();
 121                         return true;
 122                 } catch (PluginException pe1) {
 123                         /* not connected, ignore. */
 124                         return false;
 125                 }
 126         }
 127
 128         /**
 129          * Returns the own identity with the given ID.
 130          *
 131          * @param id
 132          *            The ID of the own identity
 133          * @return The own identity, or {@code null} if there is no such identity
 134          */
 135         public OwnIdentity getOwnIdentity(String id) {
 136                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 137                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 138                         if (ownIdentity.getId().equals(id)) {
 139                                 return new DefaultOwnIdentity(ownIdentity);
 140                         }
 141                 }
 142                 return null;
 143         }
 144
 145         /**
 146          * Returns all own identities.
 147          *
 148          * @return All own identities
 149          */
 150         public Set<OwnIdentity> getAllOwnIdentities() {
 151                 return new HashSet<OwnIdentity>(currentOwnIdentities.values());
 152         }
 153
 154         //
 155         // SERVICE METHODS
 156         //
 157
 158         /**
 159          * {@inheritDoc}
 160          */
 161         @Override
 162         protected void serviceRun() {
 163                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 164                 while (!shouldStop()) {
 165                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 166                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 167
 168                         Set<OwnIdentity> ownIdentities = null;
 169                         boolean identitiesLoaded = false;
 170                         try {
 171                                 /* get all identities with the wanted context from WoT. */
 172                                 ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 173
 174                                 /* load trusted identities. */
 175                                 for (OwnIdentity ownIdentity : ownIdentities) {
 176                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 177                                                 continue;
 178                                         }
 179                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 180
 181                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 182                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 183                                         currentIdentities.put(ownIdentity, identities);
 184                                         for (Identity identity : trustedIdentities) {
 185                                                 identities.put(identity.getId(), identity);
 186                                         }
 187                                 }
 188                                 identitiesLoaded = true;
 189                         } catch (WebOfTrustException wote1) {
 190                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 191                         }
 192
 193                         if (identitiesLoaded) {
 194
 195                                 /* check for changes. */
 196                                 checkOwnIdentities(currentOwnIdentities);
 197
 198                                 /* now check for changes in remote identities. */
 199                                 for (OwnIdentity ownIdentity : currentOwnIdentities.values()) {
 200
 201                                         /* find new identities. */
 202                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 203                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 204                                                         identityListenerManager.fireIdentityAdded(ownIdentity, currentIdentity);
 205                                                 }
 206                                         }
 207
 208                                         /* find removed identities. */
 209                                         if (oldIdentities.containsKey(ownIdentity)) {
 210                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 211                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 212                                                                 identityListenerManager.fireIdentityRemoved(ownIdentity, oldIdentity);
 213                                                         }
 214                                                 }
 215
 216                                                 /* check for changes in the contexts. */
 217                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 218                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 219                                                                 continue;
 220                                                         }
 221                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 222                                                         Set<String> oldContexts = oldIdentity.getContexts();
 223                                                         Set<String> newContexts = newIdentity.getContexts();
 224                                                         if (oldContexts.size() != newContexts.size()) {
 225                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 226                                                                 continue;
 227                                                         }
 228                                                         for (String oldContext : oldContexts) {
 229                                                                 if (!newContexts.contains(oldContext)) {
 230                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 231                                                                         break;
 232                                                                 }
 233                                                         }
 234                                                 }
 235
 236                                                 /* check for changes in the properties. */
 237                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 238                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 239                                                                 continue;
 240                                                         }
 241                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 242                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 243                                                         Map<String, String> newProperties = newIdentity.getProperties();
 244                                                         if (oldProperties.size() != newProperties.size()) {
 245                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 246                                                                 continue;
 247                                                         }
 248                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 249                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 250                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 251                                                                         break;
 252                                                                 }
 253                                                         }
 254                                                 }
 255                                         }
 256                                 }
 257
 258                                 /* remember the current set of identities. */
 259                                 oldIdentities = currentIdentities;
 260                         }
 261
 262                         /* wait a minute before checking again. */
 263                         sleep(60 * 1000);
 264                 }
 265         }
 266
 267         //
 268         // PRIVATE METHODS
 269         //
 270
 271         /**
 272          * Checks the given new list of own identities for added or removed own
 273          * identities, as compared to {@link #currentOwnIdentities}.
 274          *
 275          * @param newOwnIdentities
 276          *            The new own identities
 277          */
 278         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 279                 synchronized (syncObject) {
 280
 281                         /* find removed own identities: */
 282                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 283                                 OwnIdentity newOwnIdentity = newOwnIdentities.get(oldOwnIdentity.getId());
 284                                 if ((newOwnIdentity == null) || ((context != null) && oldOwnIdentity.hasContext(context) && !newOwnIdentity.hasContext(context))) {
 285                                         identityListenerManager.fireOwnIdentityRemoved(new DefaultOwnIdentity(oldOwnIdentity));
 286                                 }
 287                         }
 288
 289                         /* find added own identities. */
 290                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 291                                 OwnIdentity oldOwnIdentity = currentOwnIdentities.get(currentOwnIdentity.getId());
 292                                 if (((oldOwnIdentity == null) && ((context == null) || currentOwnIdentity.hasContext(context))) || ((oldOwnIdentity != null) && (context != null) && (!oldOwnIdentity.hasContext(context) && currentOwnIdentity.hasContext(context)))) {
 293                                         identityListenerManager.fireOwnIdentityAdded(new DefaultOwnIdentity(currentOwnIdentity));
 294                                 }
 295                         }
 296
 297                         currentOwnIdentities.clear();
 298                         currentOwnIdentities.putAll(newOwnIdentities);
 299                 }
 300         }
 301
 302 }