import java.util.Collection;
import java.util.HashSet;
import java.util.List;
+import java.util.concurrent.Callable;
+import net.pterodactylus.util.collection.Memoizer;
import net.pterodactylus.util.database.Database;
import net.pterodactylus.util.database.DatabaseException;
import net.pterodactylus.util.database.Field;
import net.pterodactylus.util.database.Join;
import net.pterodactylus.util.database.Join.JoinType;
+import net.pterodactylus.util.database.ObjectCreator;
import net.pterodactylus.util.database.OrderField;
import net.pterodactylus.util.database.OrderField.Order;
import net.pterodactylus.util.database.Parameter.StringParameter;
*/
public class DataManager {
+ private final ObjectCreator<Artist> artistCreator = new ArtistCreator();
+
private final Database database;
public DataManager(Database database) {
public Collection<Artist> getAllArtists() throws DatabaseException {
Query query = new Query(Type.SELECT, "ARTISTS");
query.addField(new Field("ARTISTS.*"));
- query.addField(new Field("GROUP_ARTISTS.*"));
- query.addField(new Field("GROUPS.*"));
- query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("ARTISTS.ID"), new Field("GROUP_ARTISTS.ARTIST")));
- query.addJoin(new Join(JoinType.INNER, "GROUPS", new Field("GROUP_ARTISTS.GROUP_"), new Field("GROUPS.ID")));
- query.addOrderField(new OrderField(new Field("ARTISTS.ID")));
- ArtistLoader artistLoader = new ArtistLoader();
- database.process(query, artistLoader);
- return artistLoader.all();
+ return database.getMultiple(query, artistCreator);
}
public Artist getArtistById(String id) throws DatabaseException {
return trackLoader.get();
}
+ public Collection<Track> getTracksByArtist(String artistId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "TRACKS");
+ query.addField(new Field("TRACKS.*"));
+ query.addField(new Field("TRACK_ARTISTS.*"));
+ query.addField(new Field("ARTISTS.*"));
+ query.addField(new Field("TRACK_STYLES.*"));
+ query.addField(new Field("STYLES.*"));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACKS.ID"), new Field("TRACK_ARTISTS.TRACK")));
+ query.addJoin(new Join(JoinType.INNER, "ARTISTS", new Field("TRACK_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_STYLES", new Field("TRACKS.ID"), new Field("TRACK_STYLES.TRACK")));
+ query.addJoin(new Join(JoinType.INNER, "STYLES", new Field("TRACK_STYLES.STYLE"), new Field("STYLES.ID")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("ARTISTS.ID", new StringParameter(artistId))));
+ query.addOrderField(new OrderField(new Field("TRACKS.ID"), Order.ASCENDING));
+ query.addOrderField(new OrderField(new Field("TRACK_ARTISTS.DISPLAY_ORDER"), Order.ASCENDING));
+ TrackLoader trackLoader = new TrackLoader();
+ database.process(query, trackLoader);
+ return trackLoader.all();
+ }
+
+ public Collection<Group> getGroupsByArtist(String artistId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "GROUPS");
+ query.addField(new Field("GROUPS.*"));
+ query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("GROUPS.ID"), new Field("GROUP_ARTISTS.GROUP_")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("GROUP_ARTISTS.ARTIST", new StringParameter(artistId))));
+ return database.getMultiple(query, DefaultGroup.CREATOR);
+ }
+
private class TrackLoader implements ResultProcessor {
private final List<Track> loadedTracks = new ArrayList<Track>();
private Track track;
+ public Track get() {
+ return loadedTracks.isEmpty() ? null : loadedTracks.get(0);
+ }
+
+ public List<Track> all() {
+ return loadedTracks;
+ }
+
/**
* {@inheritDoc}
*/
track = new DefaultTrack(trackId).name(resultSet.getString("TRACKS.NAME")).artists(new ArrayList<Artist>()).styles(new HashSet<Style>());
loadedTracks.add(track);
}
- Artist artist = new DefaultArtist(resultSet.getString("ARTISTS.ID")).name(resultSet.getString("ARTISTS.NAME"));
+ Artist artist = new LazyArtist(resultSet.getString("ARTISTS.ID")).name(resultSet.getString("ARTISTS.NAME"));
if (!track.artists().contains(artist)) {
track.artists().add(artist);
}
track.styles().add(style);
}
- public Track get() {
- return loadedTracks.isEmpty() ? null : loadedTracks.get(0);
- }
-
}
private class ArtistLoader implements ResultProcessor {
private final List<Artist> artists = new ArrayList<Artist>();
private Artist artist;
+ public Artist get() {
+ return artists.isEmpty() ? null : artists.get(0);
+ }
+
public List<Artist> all() {
return artists;
}
public void processResult(ResultSet resultSet) throws SQLException {
String artistId = resultSet.getString("ARTISTS.ID");
if ((artist == null) || (!artist.id().equals(artistId))) {
- artist = new DefaultArtist(artistId).name(resultSet.getString("ARTISTS.NAME")).groups(new HashSet<Group>());
+ artist = new LazyArtist(artistId).name(resultSet.getString("ARTISTS.NAME")).groups(new HashSet<Group>());
artists.add(artist);
}
}
+ private class LazyArtist extends DefaultArtist {
+
+ private final Memoizer<Void> tracksMemoizer = new Memoizer<Void>(new Callable<Void>() {
+ public Void call() throws DatabaseException {
+ if (!hasValue("tracks")) {
+ value("tracks", Collection.class).set(getTracksByArtist(id()));
+ }
+ return null;
+ }
+ });
+
+ private final Memoizer<Void> groupsMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("groups")) {
+ value("groups", Collection.class).set(getGroupsByArtist(id()));
+ }
+ return null;
+ }
+
+ });
+
+ public LazyArtist(String id) {
+ super(id);
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Group> groups() {
+ groupsMemoizer.get();
+ return super.groups();
+ }
+
+ public Collection<Track> tracks() {
+ tracksMemoizer.get();
+ return super.tracks();
+ }
+
+ }
+
+ private class ArtistCreator implements ObjectCreator<Artist> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Artist createObject(ResultSet resultSet) throws SQLException {
+ return new LazyArtist(resultSet.getString("ARTISTS.ID")).name(resultSet.getString("ARTISTS.NAME"));
+ }
+
+ }
+
}
projects / demoscenemusic.git / blobdiff