src/main/java/net/pterodactylus/demoscenemusic/data/DataManager.java

   1 /*
   2  * DemosceneMusic - DataManager.java - Copyright © 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.demoscenemusic.data;
  19
  20 import java.sql.ResultSet;
  21 import java.sql.SQLException;
  22 import java.util.Collection;
  23 import java.util.EnumMap;
  24 import java.util.HashSet;
  25 import java.util.List;
  26 import java.util.Map;
  27 import java.util.concurrent.Callable;
  28
  29 import net.pterodactylus.demoscenemusic.data.Track.Relationship;
  30 import net.pterodactylus.util.collection.Memoizer;
  31 import net.pterodactylus.util.database.Database;
  32 import net.pterodactylus.util.database.DatabaseException;
  33 import net.pterodactylus.util.database.Field;
  34 import net.pterodactylus.util.database.Join;
  35 import net.pterodactylus.util.database.Join.JoinType;
  36 import net.pterodactylus.util.database.ObjectCreator;
  37 import net.pterodactylus.util.database.OrderField;
  38 import net.pterodactylus.util.database.Parameter.StringParameter;
  39 import net.pterodactylus.util.database.Query;
  40 import net.pterodactylus.util.database.Query.Type;
  41 import net.pterodactylus.util.database.ResultProcessor;
  42 import net.pterodactylus.util.database.ValueField;
  43 import net.pterodactylus.util.database.ValueFieldWhereClause;
  44
  45 /**
  46  * Interface between the database and the application.
  47  *
  48  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  49  */
  50 public class DataManager {
  51
  52         /** The artist object creator. */
  53         @SuppressWarnings("synthetic-access")
  54         private final ObjectCreator<Artist> artistCreator = new ArtistCreator();
  55
  56         /** The group object creator. */
  57         @SuppressWarnings("synthetic-access")
  58         private final ObjectCreator<Group> groupCreator = new GroupCreator();
  59
  60         /** The track object creator. */
  61         @SuppressWarnings("synthetic-access")
  62         private final ObjectCreator<Track> trackCreator = new TrackCreator();
  63
  64         /** The style object creator. */
  65         @SuppressWarnings("synthetic-access")
  66         private final ObjectCreator<Style> styleCreator = new StyleCreator();
  67
  68         /** The database. */
  69         private final Database database;
  70
  71         /**
  72          * Creates a new data manager.
  73          *
  74          * @param database
  75          *            The database to operate on
  76          */
  77         public DataManager(Database database) {
  78                 this.database = database;
  79         }
  80
  81         /**
  82          * Returns all artists.
  83          *
  84          * @return All artists
  85          * @throws DatabaseException
  86          *             if a database error occurs
  87          */
  88         public Collection<Artist> getAllArtists() throws DatabaseException {
  89                 Query query = new Query(Type.SELECT, "ARTISTS");
  90                 query.addField(new Field("ARTISTS.*"));
  91                 return database.getMultiple(query, artistCreator);
  92         }
  93
  94         /**
  95          * Returns the artist with the given ID.
  96          *
  97          * @param id
  98          *            The ID of the artist
  99          * @return The artist with the given ID, or {@code null} if there is no
 100          *         artist with the given ID
 101          * @throws DatabaseException
 102          *             if a database error occurs
 103          */
 104         public Artist getArtistById(String id) throws DatabaseException {
 105                 Query query = new Query(Type.SELECT, "ARTISTS");
 106                 query.addField(new Field("ARTISTS.*"));
 107                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("ARTISTS.ID", new StringParameter(id))));
 108                 return database.getSingle(query, artistCreator);
 109         }
 110
 111         /**
 112          * Returns all artists that belong to the group with the given ID.
 113          *
 114          * @param groupId
 115          *            The ID of the group
 116          * @return All artists belonging to the given group
 117          * @throws DatabaseException
 118          *             if a database error occurs
 119          */
 120         public Collection<Artist> getArtistsByGroup(String groupId) throws DatabaseException {
 121                 Query query = new Query(Type.SELECT, "ARTISTS");
 122                 query.addField(new Field("ARTISTS.*"));
 123                 query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("ARTISTS.ID"), new Field("GROUP_ARTISTS.ARTIST")));
 124                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("GROUP_ARTISTS.GROUP_", new StringParameter(groupId))));
 125                 return database.getMultiple(query, artistCreator);
 126         }
 127
 128         /**
 129          * Returns all artists involved in the track with the given ID.
 130          *
 131          * @param trackId
 132          *            The ID of the track
 133          * @return All artists involved in the track, in preferred order
 134          * @throws DatabaseException
 135          *             if a database error occurs
 136          */
 137         public List<Artist> getArtistsByTrack(String trackId) throws DatabaseException {
 138                 Query query = new Query(Type.SELECT, "ARTISTS");
 139                 query.addField(new Field("ARTISTS.*"));
 140                 query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACK_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
 141                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_ARTISTS.TRACK", new StringParameter(trackId))));
 142                 query.addOrderField(new OrderField(new Field("TRACK_ARTISTS.DISPLAY_ORDER")));
 143                 return database.getMultiple(query, artistCreator);
 144         }
 145
 146         /**
 147          * Returns all remix artists involved in the track with the given ID.
 148          *
 149          * @param trackId
 150          *            The ID of the track
 151          * @return All remix artists involved in the track, in preferred order
 152          * @throws DatabaseException
 153          *             if a database error occurs
 154          */
 155         public List<Artist> getRemixArtistsByTrack(String trackId) throws DatabaseException {
 156                 Query query = new Query(Type.SELECT, "ARTISTS");
 157                 query.addField(new Field("ARTISTS.*"));
 158                 query.addJoin(new Join(JoinType.INNER, "TRACK_REMIX_ARTISTS", new Field("TRACK_REMIX_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
 159                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_REMIX_ARTISTS.TRACK", new StringParameter(trackId))));
 160                 query.addOrderField(new OrderField(new Field("TRACK_REMIX_ARTISTS.DISPLAY_ORDER")));
 161                 return database.getMultiple(query, artistCreator);
 162         }
 163
 164         /**
 165          * Returns all related tracks for the track with the given ID.
 166          *
 167          * @param trackId
 168          *            The ID of the tracks
 169          * @return A mapping from relationship to all tracks that match the relation
 170          * @throws DatabaseException
 171          *             if a database error occurs
 172          */
 173         public Map<Relationship, Collection<Track>> getRelatedTracksByTrack(String trackId) throws DatabaseException {
 174                 Query query = new Query(Type.SELECT, "TRACKS");
 175                 query.addField(new Field("TRACKS.*"));
 176                 query.addField(new Field("TRACK_RELATIONS.*"));
 177                 query.addJoin(new Join(JoinType.INNER, "TRACK_RELATIONS", new Field("TRACK_RELATIONS.TRACK"), new Field("TRACK_RELATIONS.RELATED_TRACK")));
 178                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_RELATIONS.TRACK", new StringParameter(trackId))));
 179                 final Map<Relationship, Collection<Track>> relatedTracks = new EnumMap<Relationship, Collection<Track>>(Relationship.class);
 180                 database.process(query, new ResultProcessor() {
 181
 182                         @Override
 183                         @SuppressWarnings("synthetic-access")
 184                         public void processResult(ResultSet resultSet) throws SQLException {
 185                                 Track track = trackCreator.createObject(resultSet);
 186                                 Relationship relationship = Relationship.valueOf(resultSet.getString("TRACK_RELATIONS.RELATIONSHIP"));
 187                                 if (!relatedTracks.containsKey(relationship)) {
 188                                         relatedTracks.put(relationship, new HashSet<Track>());
 189                                 }
 190                                 relatedTracks.get(relationship).add(track);
 191                         }
 192                 });
 193                 return relatedTracks;
 194         }
 195
 196         /**
 197          * Returns the track with the given ID.
 198          *
 199          * @param id
 200          *            The ID of the track
 201          * @return The track with the given ID, or {@code null} if there is no such
 202          *         track
 203          * @throws DatabaseException
 204          *             if a database error occurs
 205          */
 206         public Track getTrackById(String id) throws DatabaseException {
 207                 Query query = new Query(Type.SELECT, "TRACKS");
 208                 query.addField(new Field("TRACKS.*"));
 209                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACKS.ID", new StringParameter(id))));
 210                 return database.getSingle(query, trackCreator);
 211         }
 212
 213         /**
 214          * Returns all tracks by the artist with the given ID.
 215          *
 216          * @param artistId
 217          *            The ID of the artist
 218          * @return All tracks by the given artist
 219          * @throws DatabaseException
 220          *             if a database error occurs
 221          */
 222         public Collection<Track> getTracksByArtist(String artistId) throws DatabaseException {
 223                 Query query = new Query(Type.SELECT, "TRACKS");
 224                 query.addField(new Field("TRACKS.*"));
 225                 query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACKS.ID"), new Field("TRACK_ARTISTS.TRACK")));
 226                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_ARTISTS.ARTIST", new StringParameter(artistId))));
 227                 return database.getMultiple(query, trackCreator);
 228         }
 229
 230         /**
 231          * Returns all groups the artist with the given ID belongs to.
 232          *
 233          * @param artistId
 234          *            The ID of the artist
 235          * @return All groups the artist belongs to
 236          * @throws DatabaseException
 237          *             if a database error occurs
 238          */
 239         public Collection<Group> getGroupsByArtist(String artistId) throws DatabaseException {
 240                 Query query = new Query(Type.SELECT, "GROUPS");
 241                 query.addField(new Field("GROUPS.*"));
 242                 query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("GROUPS.ID"), new Field("GROUP_ARTISTS.GROUP_")));
 243                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("GROUP_ARTISTS.ARTIST", new StringParameter(artistId))));
 244                 return database.getMultiple(query, groupCreator);
 245         }
 246
 247         /**
 248          * Returns all styles for the track with the given ID.
 249          *
 250          * @param trackId
 251          *            The ID of the track
 252          * @return All styles for the given track
 253          * @throws DatabaseException
 254          *             if a database error occurs
 255          */
 256         public Collection<Style> getStylesByTrack(String trackId) throws DatabaseException {
 257                 Query query = new Query(Type.SELECT, "STYLES");
 258                 query.addField(new Field("STYLES.*"));
 259                 query.addJoin(new Join(JoinType.INNER, "TRACK_STYLES", new Field("STYLES.ID"), new Field("TRACK_STYLES.STYLE")));
 260                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_STYLES.TRACK", new StringParameter(trackId))));
 261                 return database.getMultiple(query, styleCreator);
 262         }
 263
 264         /**
 265          * {@link Artist} implementation that retrieves some attributes (such as
 266          * {@link #getGroups()}, and {@link #getTracks()}) from the
 267          * {@link DataManager} on demand.
 268          *
 269          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 270          */
 271         private class LazyArtist extends DefaultArtist {
 272
 273                 /** Memoizer for the tracks by this artist. */
 274                 private final Memoizer<Void> tracksMemoizer = new Memoizer<Void>(new Callable<Void>() {
 275                         @Override
 276                         public Void call() throws DatabaseException {
 277                                 if (!hasValue("tracks")) {
 278                                         getValue("tracks", Collection.class).set(getTracksByArtist(getId()));
 279                                 }
 280                                 return null;
 281                         }
 282                 });
 283
 284                 /** Memoizer for the groups of this artist. */
 285                 private final Memoizer<Void> groupsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 286
 287                         @Override
 288                         public Void call() throws Exception {
 289                                 if (!hasValue("groups")) {
 290                                         getValue("groups", Collection.class).set(getGroupsByArtist(getId()));
 291                                 }
 292                                 return null;
 293                         }
 294
 295                 });
 296
 297                 /**
 298                  * Creates a new lazy artist.
 299                  *
 300                  * @param id
 301                  *            The ID of the artist
 302                  */
 303                 public LazyArtist(String id) {
 304                         super(id);
 305                 }
 306
 307                 //
 308                 // DEFAULTARTIST METHODS
 309                 //
 310
 311                 /**
 312                  * {@inheritDoc}
 313                  */
 314                 @Override
 315                 public Collection<Group> getGroups() {
 316                         groupsMemoizer.get();
 317                         return super.getGroups();
 318                 }
 319
 320                 /**
 321                  * {@inheritDoc}
 322                  */
 323                 @Override
 324                 public Collection<Track> getTracks() {
 325                         tracksMemoizer.get();
 326                         return super.getTracks();
 327                 }
 328
 329         }
 330
 331         /**
 332          * {@link ObjectCreator} implementation that can create {@link Artist}
 333          * objects. This specific class actually creates {@link LazyArtist}
 334          * instances.
 335          *
 336          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 337          */
 338         private class ArtistCreator implements ObjectCreator<Artist> {
 339
 340                 /**
 341                  * {@inheritDoc}
 342                  */
 343                 @Override
 344                 public Artist createObject(ResultSet resultSet) throws SQLException {
 345                         return new LazyArtist(resultSet.getString("ARTISTS.ID")).setName(resultSet.getString("ARTISTS.NAME"));
 346                 }
 347
 348         }
 349
 350         /**
 351          * {@link Group} implementation that retrieves some attributes (such as
 352          * {@link #getArtists()}) from the {@link DataManager} on demand.
 353          *
 354          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 355          */
 356         private class LazyGroup extends DefaultGroup {
 357
 358                 /** Memoizer for the artist. */
 359                 private final Memoizer<Void> artistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 360
 361                         @Override
 362                         public Void call() throws Exception {
 363                                 if (!hasValue("artists")) {
 364                                         getValue("artists", Collection.class).set(getArtistsByGroup(getId()));
 365                                 }
 366                                 return null;
 367                         }
 368
 369                 });
 370
 371                 /**
 372                  * Creates a new lazy group.
 373                  *
 374                  * @param id
 375                  *            The ID of the group
 376                  */
 377                 public LazyGroup(String id) {
 378                         super(id);
 379                 }
 380
 381                 //
 382                 // DEFAULTGROUP METHODS
 383                 //
 384
 385                 /**
 386                  * {@inheritDoc}
 387                  */
 388                 @Override
 389                 public Collection<Artist> getArtists() {
 390                         artistsMemoizer.get();
 391                         return super.getArtists();
 392                 }
 393
 394         }
 395
 396         /**
 397          * {@link ObjectCreator} implementation that can create {@link Group}
 398          * objects. This specific implementation creates {@link LazyGroup}
 399          * instances.
 400          *
 401          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 402          */
 403         private class GroupCreator implements ObjectCreator<Group> {
 404
 405                 /**
 406                  * {@inheritDoc}
 407                  */
 408                 @Override
 409                 public Group createObject(ResultSet resultSet) throws SQLException {
 410                         return new LazyGroup(resultSet.getString("GROUPS.ID")).setName(resultSet.getString("GROUPS.NAME")).setUrl(resultSet.getString("GROUPS.URL"));
 411                 }
 412
 413         }
 414
 415         /**
 416          * {@link Track} implementation that retrieves some attributes (such as
 417          * {@link #getArtists()}, and {@link #getStyles()}) from the
 418          * {@link DataManager} on demand.
 419          *
 420          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 421          */
 422         private class LazyTrack extends DefaultTrack {
 423
 424                 /** Memoizer for the artists. */
 425                 private final Memoizer<Void> artistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 426
 427                         @Override
 428                         public Void call() throws Exception {
 429                                 if (!hasValue("artists")) {
 430                                         getValue("artists", List.class).set(getArtistsByTrack(getId()));
 431                                 }
 432                                 return null;
 433                         }
 434
 435                 });
 436
 437                 /** Memoizer for the styles. */
 438                 private final Memoizer<Void> stylesMemoizer = new Memoizer<Void>(new Callable<Void>() {
 439
 440                         @Override
 441                         public Void call() throws Exception {
 442                                 if (!hasValue("styles")) {
 443                                         getValue("styles", Collection.class).set(getStylesByTrack(getId()));
 444                                 }
 445                                 return null;
 446                         }
 447
 448                 });
 449
 450                 /** Memoizer for the remix artists. */
 451                 private final Memoizer<Void> remixArtistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 452
 453                         @Override
 454                         public Void call() throws Exception {
 455                                 if (!hasValue("remixArtists")) {
 456                                         getValue("remixArtists", List.class).set(getRemixArtistsByTrack(getId()));
 457                                 }
 458                                 return null;
 459                         }
 460
 461                 });
 462
 463                 /** Memoizer for the related tracks. */
 464                 private final Memoizer<Void> relatedTracksMemoizer = new Memoizer<Void>(new Callable<Void>() {
 465
 466                         @Override
 467                         public Void call() throws Exception {
 468                                 if (!hasValue("relatedTracks")) {
 469                                         getValue("relatedTracks", Map.class).set(getRelatedTracksByTrack(getId()));
 470                                 }
 471                                 return null;
 472                         }
 473                 });
 474
 475                 /**
 476                  * Creates a new track.
 477                  *
 478                  * @param id
 479                  *            The ID of the track
 480                  */
 481                 public LazyTrack(String id) {
 482                         super(id);
 483                 }
 484
 485                 //
 486                 // DEFAULTTRACK METHODS
 487                 //
 488
 489                 /**
 490                  * {@inheritDoc}
 491                  */
 492                 @Override
 493                 public List<Artist> getArtists() {
 494                         artistsMemoizer.get();
 495                         return super.getArtists();
 496                 }
 497
 498                 /**
 499                  * {@inheritDoc}
 500                  */
 501                 @Override
 502                 public Collection<Style> getStyles() {
 503                         stylesMemoizer.get();
 504                         return super.getStyles();
 505                 }
 506
 507                 /**
 508                  * {@inheritDoc}
 509                  */
 510                 @Override
 511                 public List<Artist> getRemixArtists() {
 512                         remixArtistsMemoizer.get();
 513                         return super.getRemixArtists();
 514                 }
 515
 516                 /**
 517                  * {@inheritDoc}
 518                  */
 519                 @Override
 520                 public Map<Relationship, Collection<Track>> getRelatedTracks() {
 521                         relatedTracksMemoizer.get();
 522                         return super.getRelatedTracks();
 523                 }
 524
 525         }
 526
 527         /**
 528          * {@link ObjectCreator} implementation that can create {@link Track}
 529          * objects. This specific implementation creates {@link LazyTrack}
 530          * instances.
 531          *
 532          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 533          */
 534         private class TrackCreator implements ObjectCreator<Track> {
 535
 536                 /**
 537                  * {@inheritDoc}
 538                  */
 539                 @Override
 540                 public Track createObject(ResultSet resultSet) throws SQLException {
 541                         return new LazyTrack(resultSet.getString("TRACKS.ID")).setName(resultSet.getString("TRACKS.NAME")).setRemix(resultSet.getString("TRACKS.REMIX"));
 542                 }
 543
 544         }
 545
 546         /**
 547          * {@link ObjectCreator} implementation that can create {@link Style}
 548          * objects.
 549          *
 550          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 551          */
 552         private class StyleCreator implements ObjectCreator<Style> {
 553
 554                 /**
 555                  * {@inheritDoc}
 556                  */
 557                 @Override
 558                 public Style createObject(ResultSet resultSet) throws SQLException {
 559                         return new DefaultStyle(resultSet.getString("STYLES.ID")).setName(resultSet.getString("STYLES.NAME"));
 560                 }
 561
 562         }
 563
 564 }