src/main/java/net/pterodactylus/sone/database/memory/MemoryDatabase.java

   1 /*
   2  * Sone - MemoryDatabase.java - Copyright © 2013–2016 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.database.memory;
  19
  20 import static com.google.common.base.Optional.fromNullable;
  21 import static com.google.common.base.Preconditions.checkNotNull;
  22 import static com.google.common.base.Predicates.not;
  23 import static com.google.common.collect.FluentIterable.from;
  24 import static net.pterodactylus.sone.data.Reply.TIME_COMPARATOR;
  25 import static net.pterodactylus.sone.data.Sone.LOCAL_SONE_FILTER;
  26 import static net.pterodactylus.sone.data.Sone.toAllAlbums;
  27 import static net.pterodactylus.sone.data.Sone.toAllImages;
  28
  29 import java.util.Collection;
  30 import java.util.Collections;
  31 import java.util.Comparator;
  32 import java.util.HashMap;
  33 import java.util.HashSet;
  34 import java.util.List;
  35 import java.util.Map;
  36 import java.util.Set;
  37 import java.util.concurrent.locks.ReadWriteLock;
  38 import java.util.concurrent.locks.ReentrantReadWriteLock;
  39
  40 import javax.annotation.Nonnull;
  41 import javax.annotation.Nullable;
  42
  43 import net.pterodactylus.sone.data.Album;
  44 import net.pterodactylus.sone.data.Image;
  45 import net.pterodactylus.sone.data.Post;
  46 import net.pterodactylus.sone.data.PostReply;
  47 import net.pterodactylus.sone.data.Sone;
  48 import net.pterodactylus.sone.data.impl.AlbumBuilderImpl;
  49 import net.pterodactylus.sone.data.impl.ImageBuilderImpl;
  50 import net.pterodactylus.sone.database.AlbumBuilder;
  51 import net.pterodactylus.sone.database.Database;
  52 import net.pterodactylus.sone.database.DatabaseException;
  53 import net.pterodactylus.sone.database.ImageBuilder;
  54 import net.pterodactylus.sone.database.PostBuilder;
  55 import net.pterodactylus.sone.database.PostDatabase;
  56 import net.pterodactylus.sone.database.PostReplyBuilder;
  57 import net.pterodactylus.sone.database.SoneBuilder;
  58 import net.pterodactylus.sone.database.SoneProvider;
  59 import net.pterodactylus.util.config.Configuration;
  60 import net.pterodactylus.util.config.ConfigurationException;
  61
  62 import com.google.common.base.Optional;
  63 import com.google.common.base.Predicate;
  64 import com.google.common.collect.HashMultimap;
  65 import com.google.common.collect.Multimap;
  66 import com.google.common.collect.SortedSetMultimap;
  67 import com.google.common.collect.TreeMultimap;
  68 import com.google.common.util.concurrent.AbstractService;
  69 import com.google.inject.Inject;
  70 import com.google.inject.Singleton;
  71 import kotlin.jvm.functions.Function1;
  72
  73 /**
  74  * Memory-based {@link PostDatabase} implementation.
  75  *
  76  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  77  */
  78 @Singleton
  79 public class MemoryDatabase extends AbstractService implements Database {
  80
  81         /** The lock. */
  82         private final ReadWriteLock lock = new ReentrantReadWriteLock();
  83
  84         /** The Sone provider. */
  85         private final SoneProvider soneProvider;
  86
  87         /** The configuration. */
  88         private final Configuration configuration;
  89         private final ConfigurationLoader configurationLoader;
  90
  91         private final Map<String, Sone> allSones = new HashMap<String, Sone>();
  92
  93         /** All posts by their ID. */
  94         private final Map<String, Post> allPosts = new HashMap<String, Post>();
  95
  96         /** All posts by their Sones. */
  97         private final Multimap<String, Post> sonePosts = HashMultimap.create();
  98
  99         /** Whether posts are known. */
 100         private final Set<String> knownPosts = new HashSet<String>();
 101
 102         /** All post replies by their ID. */
 103         private final Map<String, PostReply> allPostReplies = new HashMap<String, PostReply>();
 104
 105         /** Replies sorted by Sone. */
 106         private final SortedSetMultimap<String, PostReply> sonePostReplies = TreeMultimap.create(new Comparator<String>() {
 107
 108                 @Override
 109                 public int compare(String leftString, String rightString) {
 110                         return leftString.compareTo(rightString);
 111                 }
 112         }, TIME_COMPARATOR);
 113
 114         /** Whether post replies are known. */
 115         private final Set<String> knownPostReplies = new HashSet<String>();
 116
 117         private final Map<String, Album> allAlbums = new HashMap<String, Album>();
 118         private final Multimap<String, Album> soneAlbums = HashMultimap.create();
 119
 120         private final Map<String, Image> allImages = new HashMap<String, Image>();
 121         private final Multimap<String, Image> soneImages = HashMultimap.create();
 122
 123         private final MemoryBookmarkDatabase memoryBookmarkDatabase;
 124         private final MemoryFriendDatabase memoryFriendDatabase;
 125
 126         /**
 127          * Creates a new memory database.
 128          *
 129          * @param soneProvider
 130          *              The Sone provider
 131          * @param configuration
 132          *              The configuration for loading and saving elements
 133          */
 134         @Inject
 135         public MemoryDatabase(SoneProvider soneProvider, Configuration configuration) {
 136                 this.soneProvider = soneProvider;
 137                 this.configuration = configuration;
 138                 this.configurationLoader = new ConfigurationLoader(configuration);
 139                 memoryBookmarkDatabase =
 140                                 new MemoryBookmarkDatabase(this, configurationLoader);
 141                 memoryFriendDatabase = new MemoryFriendDatabase(configurationLoader);
 142         }
 143
 144         //
 145         // DATABASE METHODS
 146         //
 147
 148         /**
 149          * Saves the database.
 150          *
 151          * @throws DatabaseException
 152          *              if an error occurs while saving
 153          */
 154         @Override
 155         public void save() throws DatabaseException {
 156                 saveKnownPosts();
 157                 saveKnownPostReplies();
 158         }
 159
 160         //
 161         // SERVICE METHODS
 162         //
 163
 164         /** {@inheritDocs} */
 165         @Override
 166         protected void doStart() {
 167                 memoryBookmarkDatabase.start();
 168                 loadKnownPosts();
 169                 loadKnownPostReplies();
 170                 notifyStarted();
 171         }
 172
 173         /** {@inheritDocs} */
 174         @Override
 175         protected void doStop() {
 176                 try {
 177                         memoryBookmarkDatabase.stop();
 178                         save();
 179                         notifyStopped();
 180                 } catch (DatabaseException de1) {
 181                         notifyFailed(de1);
 182                 }
 183         }
 184
 185         @Override
 186         public SoneBuilder newSoneBuilder() {
 187                 return new MemorySoneBuilder(this);
 188         }
 189
 190         @Override
 191         public void storeSone(Sone sone) {
 192                 lock.writeLock().lock();
 193                 try {
 194                         removeSone(sone);
 195
 196                         allSones.put(sone.getId(), sone);
 197                         sonePosts.putAll(sone.getId(), sone.getPosts());
 198                         for (Post post : sone.getPosts()) {
 199                                 allPosts.put(post.getId(), post);
 200                         }
 201                         sonePostReplies.putAll(sone.getId(), sone.getReplies());
 202                         for (PostReply postReply : sone.getReplies()) {
 203                                 allPostReplies.put(postReply.getId(), postReply);
 204                         }
 205                         soneAlbums.putAll(sone.getId(), toAllAlbums.apply(sone));
 206                         for (Album album : toAllAlbums.apply(sone)) {
 207                                 allAlbums.put(album.getId(), album);
 208                         }
 209                         soneImages.putAll(sone.getId(), toAllImages.apply(sone));
 210                         for (Image image : toAllImages.apply(sone)) {
 211                                 allImages.put(image.getId(), image);
 212                         }
 213                 } finally {
 214                         lock.writeLock().unlock();
 215                 }
 216         }
 217
 218         @Override
 219         public void removeSone(Sone sone) {
 220                 lock.writeLock().lock();
 221                 try {
 222                         allSones.remove(sone.getId());
 223                         Collection<Post> removedPosts = sonePosts.removeAll(sone.getId());
 224                         for (Post removedPost : removedPosts) {
 225                                 allPosts.remove(removedPost.getId());
 226                         }
 227                         Collection<PostReply> removedPostReplies =
 228                                         sonePostReplies.removeAll(sone.getId());
 229                         for (PostReply removedPostReply : removedPostReplies) {
 230                                 allPostReplies.remove(removedPostReply.getId());
 231                         }
 232                         Collection<Album> removedAlbums =
 233                                         soneAlbums.removeAll(sone.getId());
 234                         for (Album removedAlbum : removedAlbums) {
 235                                 allAlbums.remove(removedAlbum.getId());
 236                         }
 237                         Collection<Image> removedImages =
 238                                         soneImages.removeAll(sone.getId());
 239                         for (Image removedImage : removedImages) {
 240                                 allImages.remove(removedImage.getId());
 241                         }
 242                 } finally {
 243                         lock.writeLock().unlock();
 244                 }
 245         }
 246
 247         @Nonnull
 248         @Override
 249         public Function1<String, Sone> getSoneLoader() {
 250                 return new Function1<String, Sone>() {
 251                         @Override
 252                         public Sone invoke(String soneId) {
 253                                 return getSone(soneId);
 254                         }
 255                 };
 256         }
 257
 258         @Override
 259         public Sone getSone(String soneId) {
 260                 lock.readLock().lock();
 261                 try {
 262                         return allSones.get(soneId);
 263                 } finally {
 264                         lock.readLock().unlock();
 265                 }
 266         }
 267
 268         @Override
 269         public Collection<Sone> getSones() {
 270                 lock.readLock().lock();
 271                 try {
 272                         return new HashSet<Sone>(allSones.values());
 273                 } finally {
 274                         lock.readLock().unlock();
 275                 }
 276         }
 277
 278         @Override
 279         public Collection<Sone> getLocalSones() {
 280                 lock.readLock().lock();
 281                 try {
 282                         return from(allSones.values()).filter(LOCAL_SONE_FILTER).toSet();
 283                 } finally {
 284                         lock.readLock().unlock();
 285                 }
 286         }
 287
 288         @Override
 289         public Collection<Sone> getRemoteSones() {
 290                 lock.readLock().lock();
 291                 try {
 292                         return from(allSones.values())
 293                                         .filter(not(LOCAL_SONE_FILTER)) .toSet();
 294                 } finally {
 295                         lock.readLock().unlock();
 296                 }
 297         }
 298
 299         @Override
 300         public Collection<String> getFriends(Sone localSone) {
 301                 if (!localSone.isLocal()) {
 302                         return Collections.emptySet();
 303                 }
 304                 return memoryFriendDatabase.getFriends(localSone.getId());
 305         }
 306
 307         @Override
 308         public boolean isFriend(Sone localSone, String friendSoneId) {
 309                 if (!localSone.isLocal()) {
 310                         return false;
 311                 }
 312                 return memoryFriendDatabase.isFriend(localSone.getId(), friendSoneId);
 313         }
 314
 315         @Override
 316         public void addFriend(Sone localSone, String friendSoneId) {
 317                 if (!localSone.isLocal()) {
 318                         return;
 319                 }
 320                 memoryFriendDatabase.addFriend(localSone.getId(), friendSoneId);
 321         }
 322
 323         @Override
 324         public void removeFriend(Sone localSone, String friendSoneId) {
 325                 if (!localSone.isLocal()) {
 326                         return;
 327                 }
 328                 memoryFriendDatabase.removeFriend(localSone.getId(), friendSoneId);
 329         }
 330
 331         //
 332         // POSTPROVIDER METHODS
 333         //
 334
 335         /** {@inheritDocs} */
 336         @Override
 337         public Optional<Post> getPost(String postId) {
 338                 lock.readLock().lock();
 339                 try {
 340                         return fromNullable(allPosts.get(postId));
 341                 } finally {
 342                         lock.readLock().unlock();
 343                 }
 344         }
 345
 346         /** {@inheritDocs} */
 347         @Override
 348         public Collection<Post> getPosts(String soneId) {
 349                 return new HashSet<Post>(getPostsFrom(soneId));
 350         }
 351
 352         /** {@inheritDocs} */
 353         @Override
 354         public Collection<Post> getDirectedPosts(final String recipientId) {
 355                 lock.readLock().lock();
 356                 try {
 357                         return from(sonePosts.values()).filter(new Predicate<Post>() {
 358                                 @Override
 359                                 public boolean apply(Post post) {
 360                                         return post.getRecipientId().asSet().contains(recipientId);
 361                                 }
 362                         }).toSet();
 363                 } finally {
 364                         lock.readLock().unlock();
 365                 }
 366         }
 367
 368         //
 369         // POSTBUILDERFACTORY METHODS
 370         //
 371
 372         /** {@inheritDocs} */
 373         @Override
 374         public PostBuilder newPostBuilder() {
 375                 return new MemoryPostBuilder(this, soneProvider);
 376         }
 377
 378         //
 379         // POSTSTORE METHODS
 380         //
 381
 382         /** {@inheritDocs} */
 383         @Override
 384         public void storePost(Post post) {
 385                 checkNotNull(post, "post must not be null");
 386                 lock.writeLock().lock();
 387                 try {
 388                         allPosts.put(post.getId(), post);
 389                         getPostsFrom(post.getSone().getId()).add(post);
 390                 } finally {
 391                         lock.writeLock().unlock();
 392                 }
 393         }
 394
 395         /** {@inheritDocs} */
 396         @Override
 397         public void removePost(Post post) {
 398                 checkNotNull(post, "post must not be null");
 399                 lock.writeLock().lock();
 400                 try {
 401                         allPosts.remove(post.getId());
 402                         getPostsFrom(post.getSone().getId()).remove(post);
 403                         post.getSone().removePost(post);
 404                 } finally {
 405                         lock.writeLock().unlock();
 406                 }
 407         }
 408
 409         //
 410         // POSTREPLYPROVIDER METHODS
 411         //
 412
 413         @Nullable
 414         @Override
 415         public PostReply getPostReply(String id) {
 416                 lock.readLock().lock();
 417                 try {
 418                         return allPostReplies.get(id);
 419                 } finally {
 420                         lock.readLock().unlock();
 421                 }
 422         }
 423
 424         /** {@inheritDocs} */
 425         @Override
 426         public List<PostReply> getReplies(final String postId) {
 427                 lock.readLock().lock();
 428                 try {
 429                         return from(allPostReplies.values())
 430                                         .filter(new Predicate<PostReply>() {
 431                                                 @Override
 432                                                 public boolean apply(PostReply postReply) {
 433                                                         return postReply.getPostId().equals(postId);
 434                                                 }
 435                                         }).toSortedList(TIME_COMPARATOR);
 436                 } finally {
 437                         lock.readLock().unlock();
 438                 }
 439         }
 440
 441         //
 442         // POSTREPLYBUILDERFACTORY METHODS
 443         //
 444
 445         /** {@inheritDocs} */
 446         @Override
 447         public PostReplyBuilder newPostReplyBuilder() {
 448                 return new MemoryPostReplyBuilder(this, soneProvider);
 449         }
 450
 451         //
 452         // POSTREPLYSTORE METHODS
 453         //
 454
 455         /** {@inheritDocs} */
 456         @Override
 457         public void storePostReply(PostReply postReply) {
 458                 lock.writeLock().lock();
 459                 try {
 460                         allPostReplies.put(postReply.getId(), postReply);
 461                 } finally {
 462                         lock.writeLock().unlock();
 463                 }
 464         }
 465
 466         /** {@inheritDocs} */
 467         @Override
 468         public void removePostReply(PostReply postReply) {
 469                 lock.writeLock().lock();
 470                 try {
 471                         allPostReplies.remove(postReply.getId());
 472                 } finally {
 473                         lock.writeLock().unlock();
 474                 }
 475         }
 476
 477         //
 478         // ALBUMPROVDER METHODS
 479         //
 480
 481         @Nullable
 482         @Override
 483         public Album getAlbum(@Nonnull String albumId) {
 484                 lock.readLock().lock();
 485                 try {
 486                         return allAlbums.get(albumId);
 487                 } finally {
 488                         lock.readLock().unlock();
 489                 }
 490         }
 491
 492         //
 493         // ALBUMBUILDERFACTORY METHODS
 494         //
 495
 496         @Override
 497         public AlbumBuilder newAlbumBuilder() {
 498                 return new AlbumBuilderImpl();
 499         }
 500
 501         //
 502         // ALBUMSTORE METHODS
 503         //
 504
 505         @Override
 506         public void storeAlbum(Album album) {
 507                 lock.writeLock().lock();
 508                 try {
 509                         allAlbums.put(album.getId(), album);
 510                         soneAlbums.put(album.getSone().getId(), album);
 511                 } finally {
 512                         lock.writeLock().unlock();
 513                 }
 514         }
 515
 516         @Override
 517         public void removeAlbum(Album album) {
 518                 lock.writeLock().lock();
 519                 try {
 520                         allAlbums.remove(album.getId());
 521                         soneAlbums.remove(album.getSone().getId(), album);
 522                 } finally {
 523                         lock.writeLock().unlock();
 524                 }
 525         }
 526
 527         //
 528         // IMAGEPROVIDER METHODS
 529         //
 530
 531         @Nullable
 532         @Override
 533         public Image getImage(@Nonnull String imageId) {
 534                 lock.readLock().lock();
 535                 try {
 536                         return allImages.get(imageId);
 537                 } finally {
 538                         lock.readLock().unlock();
 539                 }
 540         }
 541
 542         //
 543         // IMAGEBUILDERFACTORY METHODS
 544         //
 545
 546         @Override
 547         public ImageBuilder newImageBuilder() {
 548                 return new ImageBuilderImpl();
 549         }
 550
 551         //
 552         // IMAGESTORE METHODS
 553         //
 554
 555         @Override
 556         public void storeImage(Image image) {
 557                 lock.writeLock().lock();
 558                 try {
 559                         allImages.put(image.getId(), image);
 560                         soneImages.put(image.getSone().getId(), image);
 561                 } finally {
 562                         lock.writeLock().unlock();
 563                 }
 564         }
 565
 566         @Override
 567         public void removeImage(Image image) {
 568                 lock.writeLock().lock();
 569                 try {
 570                         allImages.remove(image.getId());
 571                         soneImages.remove(image.getSone().getId(), image);
 572                 } finally {
 573                         lock.writeLock().unlock();
 574                 }
 575         }
 576
 577         @Override
 578         public void bookmarkPost(Post post) {
 579                 memoryBookmarkDatabase.bookmarkPost(post);
 580         }
 581
 582         @Override
 583         public void unbookmarkPost(Post post) {
 584                 memoryBookmarkDatabase.unbookmarkPost(post);
 585         }
 586
 587         @Override
 588         public boolean isPostBookmarked(Post post) {
 589                 return memoryBookmarkDatabase.isPostBookmarked(post);
 590         }
 591
 592         @Override
 593         public Set<Post> getBookmarkedPosts() {
 594                 return memoryBookmarkDatabase.getBookmarkedPosts();
 595         }
 596
 597         //
 598         // PACKAGE-PRIVATE METHODS
 599         //
 600
 601         /**
 602          * Returns whether the given post is known.
 603          *
 604          * @param post
 605          *              The post
 606          * @return {@code true} if the post is known, {@code false} otherwise
 607          */
 608         boolean isPostKnown(Post post) {
 609                 lock.readLock().lock();
 610                 try {
 611                         return knownPosts.contains(post.getId());
 612                 } finally {
 613                         lock.readLock().unlock();
 614                 }
 615         }
 616
 617         /**
 618          * Sets whether the given post is known.
 619          *
 620          * @param post
 621          *              The post
 622          * @param known
 623          *              {@code true} if the post is known, {@code false} otherwise
 624          */
 625         void setPostKnown(Post post, boolean known) {
 626                 lock.writeLock().lock();
 627                 try {
 628                         if (known) {
 629                                 knownPosts.add(post.getId());
 630                         } else {
 631                                 knownPosts.remove(post.getId());
 632                         }
 633                 } finally {
 634                         lock.writeLock().unlock();
 635                 }
 636         }
 637
 638         /**
 639          * Returns whether the given post reply is known.
 640          *
 641          * @param postReply
 642          *              The post reply
 643          * @return {@code true} if the given post reply is known, {@code false}
 644          *         otherwise
 645          */
 646         boolean isPostReplyKnown(PostReply postReply) {
 647                 lock.readLock().lock();
 648                 try {
 649                         return knownPostReplies.contains(postReply.getId());
 650                 } finally {
 651                         lock.readLock().unlock();
 652                 }
 653         }
 654
 655         /**
 656          * Sets whether the given post reply is known.
 657          *
 658          * @param postReply
 659          *              The post reply
 660          * @param known
 661          *              {@code true} if the post reply is known, {@code false} otherwise
 662          */
 663         void setPostReplyKnown(PostReply postReply, boolean known) {
 664                 lock.writeLock().lock();
 665                 try {
 666                         if (known) {
 667                                 knownPostReplies.add(postReply.getId());
 668                         } else {
 669                                 knownPostReplies.remove(postReply.getId());
 670                         }
 671                 } finally {
 672                         lock.writeLock().unlock();
 673                 }
 674         }
 675
 676         //
 677         // PRIVATE METHODS
 678         //
 679
 680         /**
 681          * Gets all posts for the given Sone, creating a new collection if there is
 682          * none yet.
 683          *
 684          * @param soneId
 685          *              The ID of the Sone to get the posts for
 686          * @return All posts
 687          */
 688         private Collection<Post> getPostsFrom(String soneId) {
 689                 lock.readLock().lock();
 690                 try {
 691                         return sonePosts.get(soneId);
 692                 } finally {
 693                         lock.readLock().unlock();
 694                 }
 695         }
 696
 697         /** Loads the known posts. */
 698         private void loadKnownPosts() {
 699                 Set<String> knownPosts = configurationLoader.loadKnownPosts();
 700                 lock.writeLock().lock();
 701                 try {
 702                         this.knownPosts.clear();
 703                         this.knownPosts.addAll(knownPosts);
 704                 } finally {
 705                         lock.writeLock().unlock();
 706                 }
 707         }
 708
 709         /**
 710          * Saves the known posts to the configuration.
 711          *
 712          * @throws DatabaseException
 713          *              if a configuration error occurs
 714          */
 715         private void saveKnownPosts() throws DatabaseException {
 716                 lock.readLock().lock();
 717                 try {
 718                         int postCounter = 0;
 719                         for (String knownPostId : knownPosts) {
 720                                 configuration.getStringValue("KnownPosts/" + postCounter++ + "/ID").setValue(knownPostId);
 721                         }
 722                         configuration.getStringValue("KnownPosts/" + postCounter + "/ID").setValue(null);
 723                 } catch (ConfigurationException ce1) {
 724                         throw new DatabaseException("Could not save database.", ce1);
 725                 } finally {
 726                         lock.readLock().unlock();
 727                 }
 728         }
 729
 730         /** Loads the known post replies. */
 731         private void loadKnownPostReplies() {
 732                 Set<String> knownPostReplies = configurationLoader.loadKnownPostReplies();
 733                 lock.writeLock().lock();
 734                 try {
 735                         this.knownPostReplies.clear();
 736                         this.knownPostReplies.addAll(knownPostReplies);
 737                 } finally {
 738                         lock.writeLock().unlock();
 739                 }
 740         }
 741
 742         /**
 743          * Saves the known post replies to the configuration.
 744          *
 745          * @throws DatabaseException
 746          *              if a configuration error occurs
 747          */
 748         private void saveKnownPostReplies() throws DatabaseException {
 749                 lock.readLock().lock();
 750                 try {
 751                         int replyCounter = 0;
 752                         for (String knownReplyId : knownPostReplies) {
 753                                 configuration.getStringValue("KnownReplies/" + replyCounter++ + "/ID").setValue(knownReplyId);
 754                         }
 755                         configuration.getStringValue("KnownReplies/" + replyCounter + "/ID").setValue(null);
 756                 } catch (ConfigurationException ce1) {
 757                         throw new DatabaseException("Could not save database.", ce1);
 758                 } finally {
 759                         lock.readLock().unlock();
 760                 }
 761         }
 762
 763 }