import java.sql.ResultSet;
import java.sql.SQLException;
-import java.util.ArrayList;
+import java.util.Collection;
+import java.util.EnumMap;
import java.util.HashSet;
import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.Callable;
+import net.pterodactylus.demoscenemusic.data.Track.Relationship;
+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.ObjectCreator.StringCreator;
import net.pterodactylus.util.database.OrderField;
-import net.pterodactylus.util.database.OrderField.Order;
import net.pterodactylus.util.database.Parameter.StringParameter;
import net.pterodactylus.util.database.Query;
import net.pterodactylus.util.database.Query.Type;
import net.pterodactylus.util.database.ValueFieldWhereClause;
/**
- * TODO
+ * Interface between the database and the application.
*
* @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
*/
public class DataManager {
+ /** The artist object creator. */
+ @SuppressWarnings("synthetic-access")
+ private final ObjectCreator<Artist> artistCreator = new ArtistCreator();
+
+ /** The group object creator. */
+ @SuppressWarnings("synthetic-access")
+ private final ObjectCreator<Group> groupCreator = new GroupCreator();
+
+ /** The track object creator. */
+ @SuppressWarnings("synthetic-access")
+ private final ObjectCreator<Track> trackCreator = new TrackCreator();
+
+ /** The style object creator. */
+ @SuppressWarnings("synthetic-access")
+ private final ObjectCreator<Style> styleCreator = new StyleCreator();
+
+ /** The {@link User} object creator. */
+ @SuppressWarnings("synthetic-access")
+ private final ObjectCreator<User> userCreator = new UserCreator();
+
+ /** The database. */
private final Database database;
+ /**
+ * Creates a new data manager.
+ *
+ * @param database
+ * The database to operate on
+ */
public DataManager(Database database) {
this.database = database;
}
- public Track trackById(String id) throws DatabaseException {
+ /**
+ * Returns all artists.
+ *
+ * @return All artists
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Collection<Artist> getAllArtists() throws DatabaseException {
+ Query query = new Query(Type.SELECT, "ARTISTS");
+ query.addField(new Field("ARTISTS.*"));
+ return database.getMultiple(query, artistCreator);
+ }
+
+ /**
+ * Returns the artist with the given ID.
+ *
+ * @param id
+ * The ID of the artist
+ * @return The artist with the given ID, or {@code null} if there is no
+ * artist with the given ID
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Artist getArtistById(String id) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "ARTISTS");
+ query.addField(new Field("ARTISTS.*"));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("ARTISTS.ID", new StringParameter(id))));
+ return database.getSingle(query, artistCreator);
+ }
+
+ /**
+ * Returns all artists that belong to the group with the given ID.
+ *
+ * @param groupId
+ * The ID of the group
+ * @return All artists belonging to the given group
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Collection<Artist> getArtistsByGroup(String groupId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "ARTISTS");
+ query.addField(new Field("ARTISTS.*"));
+ query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("ARTISTS.ID"), new Field("GROUP_ARTISTS.ARTIST")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("GROUP_ARTISTS.GROUP_", new StringParameter(groupId))));
+ return database.getMultiple(query, artistCreator);
+ }
+
+ /**
+ * Returns all artists involved in the track with the given ID.
+ *
+ * @param trackId
+ * The ID of the track
+ * @return All artists involved in the track, in preferred order
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public List<Artist> getArtistsByTrack(String trackId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "ARTISTS");
+ query.addField(new Field("ARTISTS.*"));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACK_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_ARTISTS.TRACK", new StringParameter(trackId))));
+ query.addOrderField(new OrderField(new Field("TRACK_ARTISTS.DISPLAY_ORDER")));
+ return database.getMultiple(query, artistCreator);
+ }
+
+ /**
+ * Creates a new artist with the given name.
+ *
+ * @param name
+ * The name of the artist
+ * @return The created artist
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Artist createArtist(String name) throws DatabaseException {
+ Query query = new Query(Type.INSERT, "ARTISTS");
+ String id = UUID.randomUUID().toString();
+ query.addValueField(new ValueField("ID", new StringParameter(id)));
+ query.addValueField(new ValueField("NAME", new StringParameter(name)));
+ database.insert(query);
+ return getArtistById(id);
+ }
+
+ /**
+ * Saves the given artist.
+ *
+ * @param artist
+ * The artist to save
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public void saveArtist(Artist artist) throws DatabaseException {
+ Query query = new Query(Type.UPDATE, "ARTISTS");
+ query.addValueField(new ValueField("NAME", new StringParameter(artist.getName())));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("ID", new StringParameter(artist.getId()))));
+ database.update(query);
+ }
+
+ /**
+ * Returns all remix artists involved in the track with the given ID.
+ *
+ * @param trackId
+ * The ID of the track
+ * @return All remix artists involved in the track, in preferred order
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public List<Artist> getRemixArtistsByTrack(String trackId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "ARTISTS");
+ query.addField(new Field("ARTISTS.*"));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_REMIX_ARTISTS", new Field("TRACK_REMIX_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_REMIX_ARTISTS.TRACK", new StringParameter(trackId))));
+ query.addOrderField(new OrderField(new Field("TRACK_REMIX_ARTISTS.DISPLAY_ORDER")));
+ return database.getMultiple(query, artistCreator);
+ }
+
+ /**
+ * Returns all related tracks for the track with the given ID.
+ *
+ * @param trackId
+ * The ID of the tracks
+ * @return A mapping from relationship to all tracks that match the relation
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Map<Relationship, Collection<Track>> getRelatedTracksByTrack(String trackId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "TRACKS");
+ query.addField(new Field("TRACKS.*"));
+ query.addField(new Field("TRACK_RELATIONS.*"));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_RELATIONS", new Field("TRACK_RELATIONS.TRACK"), new Field("TRACK_RELATIONS.RELATED_TRACK")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_RELATIONS.TRACK", new StringParameter(trackId))));
+ final Map<Relationship, Collection<Track>> relatedTracks = new EnumMap<Relationship, Collection<Track>>(Relationship.class);
+ database.process(query, new ResultProcessor() {
+
+ @Override
+ @SuppressWarnings("synthetic-access")
+ public void processResult(ResultSet resultSet) throws SQLException {
+ Track track = trackCreator.createObject(resultSet);
+ Relationship relationship = Relationship.valueOf(resultSet.getString("TRACK_RELATIONS.RELATIONSHIP"));
+ if (!relatedTracks.containsKey(relationship)) {
+ relatedTracks.put(relationship, new HashSet<Track>());
+ }
+ relatedTracks.get(relationship).add(track);
+ }
+ });
+ return relatedTracks;
+ }
+
+ /**
+ * Returns the track with the given ID.
+ *
+ * @param id
+ * The ID of the track
+ * @return The track with the given ID, or {@code null} if there is no such
+ * track
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Track getTrackById(String id) 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("TRACKS.ID", new StringParameter(id))));
- 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.get();
+ return database.getSingle(query, trackCreator);
}
- private class TrackLoader implements ResultProcessor {
+ /**
+ * Returns all tracks by the artist with the given ID.
+ *
+ * @param artistId
+ * The ID of the artist
+ * @return All tracks by the given artist
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Collection<Track> getTracksByArtist(String artistId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "TRACKS");
+ query.addField(new Field("TRACKS.*"));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACKS.ID"), new Field("TRACK_ARTISTS.TRACK")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_ARTISTS.ARTIST", new StringParameter(artistId))));
+ return database.getMultiple(query, trackCreator);
+ }
+
+ /**
+ * Returns all groups the artist with the given ID belongs to.
+ *
+ * @param artistId
+ * The ID of the artist
+ * @return All groups the artist belongs to
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ 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, groupCreator);
+ }
+
+ /**
+ * Returns all styles for the track with the given ID.
+ *
+ * @param trackId
+ * The ID of the track
+ * @return All styles for the given track
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Collection<Style> getStylesByTrack(String trackId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "STYLES");
+ query.addField(new Field("STYLES.*"));
+ query.addJoin(new Join(JoinType.INNER, "TRACK_STYLES", new Field("STYLES.ID"), new Field("TRACK_STYLES.STYLE")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_STYLES.TRACK", new StringParameter(trackId))));
+ return database.getMultiple(query, styleCreator);
+ }
+
+ /**
+ * Returns the user with the given name.
+ *
+ * @param username
+ * The name of the user
+ * @return The user, or {@code null} if the user does not exist
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public User getUserByName(String username) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "USERS");
+ query.addField(new Field("USERS.*"));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("USERS.NAME", new StringParameter(username))));
+ return database.getSingle(query, userCreator);
+ }
+
+ /**
+ * Returns the user connected with the given OpenID.
+ *
+ * @param openId
+ * The OpenID to find the user for
+ * @return The user connected with the given OpenID, or {@code null} if
+ * there is no such user
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public User getUserByOpenId(String openId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "USERS");
+ query.addField(new Field("USERS.*"));
+ query.addJoin(new Join(JoinType.INNER, "USER_OPENIDS", new Field("USER_OPENIDS.USER"), new Field("USERS.ID")));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("USER_OPENIDS.OPENID", new StringParameter(openId))));
+ return database.getSingle(query, userCreator);
+ }
+
+ /**
+ * Returns all OpenIDs connected with the user with the given ID.
+ *
+ * @param userId
+ * The ID of the user
+ * @return All OpenIDs connected with the given user
+ * @throws DatabaseException
+ * if a database error occurs
+ */
+ public Collection<String> getOpenIdsByUser(String userId) throws DatabaseException {
+ Query query = new Query(Type.SELECT, "USER_OPENIDS");
+ query.addField(new Field("USER_OPENIDS.*"));
+ query.addWhereClause(new ValueFieldWhereClause(new ValueField("USER_OPENIDS.USER", new StringParameter(userId))));
+ return database.getMultiple(query, new StringCreator("USER_OPENIDS.OPENID"));
+ }
+
+ /**
+ * {@link Artist} implementation that retrieves some attributes (such as
+ * {@link #getGroups()}, and {@link #getTracks()}) from the
+ * {@link DataManager} on demand.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class LazyArtist extends DefaultArtist {
+
+ /** Memoizer for the tracks by this artist. */
+ private final Memoizer<Void> tracksMemoizer = new Memoizer<Void>(new Callable<Void>() {
+ @Override
+ public Void call() throws DatabaseException {
+ if (!hasValue("tracks")) {
+ getValue("tracks", Collection.class).set(getTracksByArtist(getId()));
+ }
+ return null;
+ }
+ });
+
+ /** Memoizer for the groups of this artist. */
+ private final Memoizer<Void> groupsMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("groups")) {
+ getValue("groups", Collection.class).set(getGroupsByArtist(getId()));
+ }
+ return null;
+ }
+
+ });
+
+ /**
+ * Creates a new lazy artist.
+ *
+ * @param id
+ * The ID of the artist
+ */
+ public LazyArtist(String id) {
+ super(id);
+ }
+
+ //
+ // DEFAULTARTIST METHODS
+ //
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Group> getGroups() {
+ groupsMemoizer.get();
+ return super.getGroups();
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Track> getTracks() {
+ tracksMemoizer.get();
+ return super.getTracks();
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create {@link Artist}
+ * objects. This specific class actually creates {@link LazyArtist}
+ * instances.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class ArtistCreator implements ObjectCreator<Artist> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Artist createObject(ResultSet resultSet) throws SQLException {
+ return new LazyArtist(resultSet.getString("ARTISTS.ID")).setName(resultSet.getString("ARTISTS.NAME"));
+ }
+
+ }
+
+ /**
+ * {@link Group} implementation that retrieves some attributes (such as
+ * {@link #getArtists()}) from the {@link DataManager} on demand.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class LazyGroup extends DefaultGroup {
+
+ /** Memoizer for the artist. */
+ private final Memoizer<Void> artistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
+
+ @Override
+ public Void call() throws Exception {
+ if (!hasValue("artists")) {
+ getValue("artists", Collection.class).set(getArtistsByGroup(getId()));
+ }
+ return null;
+ }
+
+ });
- private final List<Track> loadedTracks = new ArrayList<Track>();
- private Track track;
+ /**
+ * Creates a new lazy group.
+ *
+ * @param id
+ * The ID of the group
+ */
+ public LazyGroup(String id) {
+ super(id);
+ }
+
+ //
+ // DEFAULTGROUP METHODS
+ //
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Artist> getArtists() {
+ artistsMemoizer.get();
+ return super.getArtists();
+ }
+
+ }
+
+ /**
+ * {@link ObjectCreator} implementation that can create {@link Group}
+ * objects. This specific implementation creates {@link LazyGroup}
+ * instances.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+ private class GroupCreator implements ObjectCreator<Group> {
/**
* {@inheritDoc}
*/
- public void processResult(ResultSet resultSet) throws SQLException {
- String trackId = resultSet.getString("TRACKS.ID");
- if ((track == null) || (!track.id().equals(trackId))) {
- track = new AbstractTrack(trackId) {
-
- public void save() {
- if (!dirty()) {
- return;
- }
- }
- }.name(resultSet.getString("TRACKS.NAME")).artists(new ArrayList<Artist>()).styles(new HashSet<Style>());
- loadedTracks.add(track);
+ @Override
+ public Group createObject(ResultSet resultSet) throws SQLException {
+ 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;
}
- Artist artist = new AbstractArtist(resultSet.getString("ARTISTS.ID")) {
- public void save() {
+ });
+
+ /** 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;
+ }
+
+ });
- }.name(resultSet.getString("ARTISTS.NAME"));
- if (!track.artists().contains(artist)) {
- track.artists().add(artist);
+ /** 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;
}
- Style style = new AbstractStyle(resultSet.getString("STYLES.ID")) {
- public void save() {
+ });
+
+ /** 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();
+ }
- }.name(resultSet.getString("STYLES.NAME"));
- track.styles().add(style);
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public Collection<Style> getStyles() {
+ stylesMemoizer.get();
+ return super.getStyles();
}
- public Track get() {
- return loadedTracks.isEmpty() ? null : loadedTracks.get(0);
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public List<Artist> getRemixArtists() {
+ remixArtistsMemoizer.get();
+ return super.getRemixArtists();
+ }
+
+ /**
+ * {@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 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 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"));
}
}