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

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