+ return new LazyGroup(resultSet.getString("GROUPS.ID")).setName(resultSet.getString("GROUPS.NAME")).setUrl(resultSet.getString("GROUPS.URL"));
+ }
+
+ }
+
+ /**
+ * {@link Track} implementation that retrieves some attributes (such as
+ * {@link #getArtists()}, and {@link #getStyles()}) from the
+ * {@link DataManager} on demand.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class LazyTrack extends DefaultTrack {
+
+ /** Memoizer for the artists. */
+ private final Memoizer<Void> artistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("artists")) {
+ getValue("artists", List.class).set(getArtistsByTrack(getId()));
+ }
+ return null;
+ }
+
+ });
+
+ /** Memoizer for the styles. */
+ private final Memoizer<Void> stylesMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("styles")) {
+ getValue("styles", Collection.class).set(getStylesByTrack(getId()));
+ }
+ return null;
+ }
+
+ });
+
+ /** Memoizer for the remix artists. */
+ private final Memoizer<Void> remixArtistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("remixArtists")) {
+ getValue("remixArtists", List.class).set(getRemixArtistsByTrack(getId()));
+ }
+ return null;
+ }
+
+ });
+
+ /** Memoizer for the track derivatives. */
+ private final Memoizer<Void> derivativesMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("derivatives")) {
+ getValue("derivatives", Collection.class).set(getTrackDerivativesByTrack(getId()));
+ }
+ return null;
+ }
+
+ });
+
+ /** Memoizer for the related tracks. */
+ private final Memoizer<Void> relatedTracksMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("relatedTracks")) {
+ getValue("relatedTracks", Map.class).set(getRelatedTracksByTrack(getId()));
+ }
+ return null;
+ }
+
+ });
+
+ /**
+ * Creates a new track.
+ *
+ * @param id
+ * The ID of the track
+ */
+ public LazyTrack(String id) {
+ super(id);
+ }
+
+ //
+ // DEFAULTTRACK METHODS
+ //
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public List<Artist> getArtists() {
+ artistsMemoizer.get();
+ return super.getArtists();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Style> getStyles() {
+ stylesMemoizer.get();
+ return super.getStyles();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public List<Artist> getRemixArtists() {
+ remixArtistsMemoizer.get();
+ return super.getRemixArtists();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<TrackDerivative> getDerivatives() {
+ derivativesMemoizer.get();
+ return super.getDerivatives();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Map<Relationship, Collection<Track>> getRelatedTracks() {
+ relatedTracksMemoizer.get();
+ return super.getRelatedTracks();
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create {@link Track}
+ * objects. This specific implementation creates {@link LazyTrack}
+ * instances.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class TrackCreator implements ObjectCreator<Track> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Track createObject(ResultSet resultSet) throws SQLException {
+ return new LazyTrack(resultSet.getString("TRACKS.ID")).setName(resultSet.getString("TRACKS.NAME")).setRemix(resultSet.getString("TRACKS.REMIX"));
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create
+ * {@link TrackDerivative} objects.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class TrackDerivativeCreator implements ObjectCreator<TrackDerivative> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public TrackDerivative createObject(ResultSet resultSet) throws SQLException {
+ return new DefaultTrackDerivative(resultSet.getString("TRACK_DERIVATIVES.ID"));
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create {@link Style}
+ * objects.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class StyleCreator implements ObjectCreator<Style> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Style createObject(ResultSet resultSet) throws SQLException {
+ return new DefaultStyle(resultSet.getString("STYLES.ID")).setName(resultSet.getString("STYLES.NAME"));
+ }
+
+ }
+
+ /**
+ * {@link Party} implementation that loads additional information only on
+ * demand.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class LazyParty extends DefaultParty {
+
+ /**
+ * Creates a new party.
+ *
+ * @param id
+ * The ID of the party
+ */
+ public LazyParty(String id) {
+ super(id);
+ }
+
+ //
+ // PARTY METHODS
+ //
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Track> getReleases() {
+ if (!hasValue("releases")) {
+ try {
+ getValue("releases", Collection.class).set(getTracksByParty(getId()));
+ } catch (DatabaseException de1) {
+ throw new RuntimeException("Could not loaded Tracks for Party " + getId() + ".", de1);
+ }
+ }
+ return super.getReleases();
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create {@link Party}
+ * objects.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class PartyCreator implements ObjectCreator<Party> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Party createObject(ResultSet resultSet) throws SQLException {
+ return new LazyParty(resultSet.getString("PARTIES.ID")).setName(resultSet.getString("PARTIES.NAME"));
+ }
+
+ }
+
+ /**
+ * {@link User} implementation that retrieves some attributes (such as
+ * {@link #getOpenIds()}) from the {@link DataManager} on demand.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class LazyUser extends DefaultUser {
+
+ /** Memoizer for a user’s OpenIDs. */
+ private final Memoizer<Void> openIdMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("openIds")) {
+ getValue("openIds", Collection.class).set(getOpenIdsByUser(getId()));
+ }
+ return null;
+ }
+ });
+
+ /**
+ * Creates a new user.
+ *
+ * @param id
+ * The ID of the user
+ */
+ public LazyUser(String id) {
+ super(id);
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<String> getOpenIds() {
+ openIdMemoizer.get();
+ return super.getOpenIds();
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create {@link User}
+ * objects. This specific implementation creates {@link LazyUser} instances.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class UserCreator implements ObjectCreator<User> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public User createObject(ResultSet resultSet) throws SQLException {
+ return new LazyUser(resultSet.getString("USERS.ID")).setName(resultSet.getString("USERS.NAME")).setPasswordHash(resultSet.getString("USERS.PASSWORD")).setLevel(resultSet.getInt("USERS.LEVEL"));