Refactor interfaces for modules (#353)

Author: w3stling

src/main/java/com/apptasticsoftware/rssreader/FeedChannel.java

@@ -13,5 +13,64 @@
 import com.apptasticsoftware.rssreader.module.wfw.WfwChannel;
 import com.apptasticsoftware.rssreader.module.youtube.YoutubeChannel;
 
+/**
+ * Unified feed channel interface combining {@link Channel} with all supported namespace module extensions.
+ * Used by {@link FeedReader} to expose data from Atom, DC, GeoRSS, iTunes, Media RSS,
+ * OpenSearch, Podcast, PSC, Slash, Spotify, WFW, and YouTube namespaces in a single object.
+ */
 public interface FeedChannel extends Channel, AtomChannel, DcChannel, GeoRssChannel, ItunesChannel, MediaRssChannel, OpenSearchChannel, PodcastChannel, PscChannel, SlashChannel, SpotifyChannel, WfwChannel, YoutubeChannel {
+
+    /**
+     * Returns {@code true} if this channel contains Atom namespace data.
+     * Always check this before accessing any Atom-specific fields.
+     */
+    boolean hasAtomChannel();
+
+    /**
+     * Returns {@code true} if this channel contains Dublin Core (DC) namespace data.
+     * Always check this before accessing any DC-specific fields.
+     */
+    boolean hasDcChannel();
+
+    /**
+     * Returns {@code true} if this channel contains GeoRSS namespace data.
+     * Always check this before accessing any GeoRSS-specific fields.
+     */
+    boolean hasGeoRssChannel();
+
+    /**
+     * Returns {@code true} if this channel contains iTunes namespace data.
+     * Always check this before accessing any iTunes-specific fields.
+     */
+    boolean hasItunesChannel();
+
+    /**
+     * Returns {@code true} if this channel contains Media RSS namespace data.
+     * Always check this before accessing any Media RSS-specific fields.
+     */
+    boolean hasMediaRssChannel();
+
+    /**
+     * Returns {@code true} if this channel contains OpenSearch namespace data.
+     * Always check this before accessing any OpenSearch-specific fields.
+     */
+    boolean hasOpenSearchChannel();
+
+    /**
+     * Returns {@code true} if this channel contains Podcast namespace data.
+     * Always check this before accessing any Podcast-specific fields.
+     */
+    boolean hasPodcastChannel();
+
+    /**
+     * Returns {@code true} if this channel contains Spotify namespace data.
+     * Always check this before accessing any Spotify-specific fields.
+     */
+    boolean hasSpotifyChannel();
+
+    /**
+     * Returns {@code true} if this channel contains YouTube namespace data.
+     * Always check this before accessing any YouTube-specific fields.
+     */
+    boolean hasYoutubeChannel();
 }

src/main/java/com/apptasticsoftware/rssreader/FeedItem.java

@@ -13,6 +13,73 @@
 import com.apptasticsoftware.rssreader.module.wfw.WfwItem;
 import com.apptasticsoftware.rssreader.module.youtube.YoutubeItem;
 
+/**
+ * Unified feed item interface combining {@link Item} with all supported namespace module extensions.
+ * Used by {@link FeedReader} to expose data from Atom, DC, GeoRSS, iTunes, Media RSS,
+ * OpenSearch, Podcast, PSC, Slash, Spotify, WFW, and YouTube namespaces in a single object.
+ */
 public interface FeedItem extends Item, AtomItem, DcItem, GeoRssItem, ItunesItem, MediaRssItem, OpenSearchItem, PodcastItem, PscItem, SlashItem, SpotifyItem, WfwItem, YoutubeItem {
 
+    @Override
+    FeedChannel getChannel();
+
+    /**
+     * Returns {@code true} if this item contains Atom namespace data.
+     * Always check this before accessing any Atom-specific fields.
+     */
+    boolean hasAtomItem();
+
+    /**
+     * Returns {@code true} if this item contains Dublin Core (DC) namespace data.
+     * Always check this before accessing any DC-specific fields.
+     */
+    boolean hasDcItem();
+
+    /**
+     * Returns {@code true} if this item contains GeoRSS namespace data.
+     * Always check this before accessing any GeoRSS-specific fields.
+     */
+    boolean hasGeoRssItem();
+
+    /**
+     * Returns {@code true} if this item contains iTunes namespace data.
+     * Always check this before accessing any iTunes-specific fields.
+     */
+    boolean hasItunesItem();
+
+    /**
+     * Returns {@code true} if this item contains Media RSS namespace data.
+     * Always check this before accessing any Media RSS-specific fields.
+     */
+    boolean hasMediaRssItem();
+
+    /**
+     * Returns {@code true} if this item contains Podcast namespace data.
+     * Always check this before accessing any Podcast-specific fields.
+     */
+    boolean hasPodcastItem();
+
+    /**
+     * Returns {@code true} if this item contains PSC (Podlove Simple Chapters) namespace data.
+     * Always check this before accessing any PSC-specific fields.
+     */
+    boolean hasPscItem();
+
+    /**
+     * Returns {@code true} if this item contains Slash namespace data.
+     * Always check this before accessing any Slash-specific fields.
+     */
+    boolean hasSlashItem();
+
+    /**
+     * Returns {@code true} if this item contains WFW (Well-Formed Web) namespace data.
+     * Always check this before accessing any WFW-specific fields.
+     */
+    boolean hasWfwItem();
+
+    /**
+     * Returns {@code true} if this item contains YouTube namespace data.
+     * Always check this before accessing any YouTube-specific fields.
+     */
+    boolean hasYoutubeItem();
 }

src/main/java/com/apptasticsoftware/rssreader/internal/FeedChannelImpl.java

@@ -22,17 +22,26 @@
 import com.apptasticsoftware.rssreader.module.youtube.internal.YoutubeChannelDataImpl;
 
 import java.util.Objects;
+import com.apptasticsoftware.rssreader.module.atom.internal.AtomChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.dc.internal.DcChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.georss.internal.GeoRssChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.itunes.internal.ItunesChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.mediarss.internal.MediaRssChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.opensearch.internal.OpenSearchChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.podcast.internal.PodcastChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.spotify.internal.SpotifyChannelDataProvider;
+import com.apptasticsoftware.rssreader.module.youtube.internal.YoutubeChannelDataProvider;
 
-public class FeedChannelImpl extends ChannelImpl implements FeedChannel {
-    private final AtomChannelData atomChannelData = new AtomChannelDataImpl();
-    private final DcChannelData dcChannelData = new DcChannelDataImpl();
-    private final GeoRssChannelData geoRssChannelData = new GeoRssChannelDataImpl();
-    private final ItunesChannelData itunesChannelData = new ItunesChannelDataImpl();
-    private final MediaRssChannelData mediaRssChannelData = new MediaRssChannelDataImpl();
-    private final OpenSearchChannelData openSearchChannelData = new OpenSearchChannelDataImpl();
-    private final PodcastChannelData podcastChannelData = new PodcastChannelDataImpl();
-    private final SpotifyChannelData spotifyChannelData = new SpotifyChannelDataImpl();
-    private final YoutubeChannelData youtubeChannelData = new YoutubeChannelDataImpl();
+public class FeedChannelImpl extends ChannelImpl implements FeedChannel, AtomChannelDataProvider, DcChannelDataProvider, GeoRssChannelDataProvider, ItunesChannelDataProvider, MediaRssChannelDataProvider, OpenSearchChannelDataProvider, PodcastChannelDataProvider, SpotifyChannelDataProvider, YoutubeChannelDataProvider {
+    private AtomChannelData atomChannelData;
+    private DcChannelData dcChannelData;
+    private GeoRssChannelData geoRssChannelData;
+    private ItunesChannelData itunesChannelData;
+    private MediaRssChannelData mediaRssChannelData;
+    private OpenSearchChannelData openSearchChannelData;
+    private PodcastChannelData podcastChannelData;
+    private SpotifyChannelData spotifyChannelData;
+    private YoutubeChannelData youtubeChannelData;
 
     /**
      * Constructor
@@ -44,47 +53,119 @@ public FeedChannelImpl(DateTimeParser dateTimeParser) {
     }
 
     @Override
-    public AtomChannelData getAtomChannelData() {
+    public boolean hasAtomChannel() {
+        return atomChannelData != null;
+    }
+
+    @Override
+    public AtomChannelData atomChannelData() {
+        if  (atomChannelData == null) {
+            atomChannelData = new AtomChannelDataImpl();
+        }
         return atomChannelData;
     }
 
     @Override
-    public DcChannelData getDcChannelData() {
+    public boolean hasDcChannel() {
+        return dcChannelData != null;
+    }
+
+    @Override
+    public DcChannelData dcChannelData() {
+        if (dcChannelData == null) {
+            dcChannelData = new DcChannelDataImpl();
+        }
         return dcChannelData;
     }
 
     @Override
-    public GeoRssChannelData getGeoRssChannelData() {
+    public boolean hasGeoRssChannel() {
+        return geoRssChannelData != null;
+    }
+
+    @Override
+    public GeoRssChannelData geoRssChannelData() {
+        if (geoRssChannelData == null) {
+            geoRssChannelData = new GeoRssChannelDataImpl();
+        }
         return geoRssChannelData;
     }
 
     @Override
-    public ItunesChannelData getItunesChannelData() {
+    public boolean hasItunesChannel() {
+        return itunesChannelData != null;
+    }
+
+    @Override
+    public ItunesChannelData itunesChannelData() {
+        if (itunesChannelData == null) {
+            itunesChannelData = new ItunesChannelDataImpl();
+        }
         return itunesChannelData;
     }
 
     @Override
-    public MediaRssChannelData getMediaRssChannelData() {
+    public boolean hasMediaRssChannel() {
+        return mediaRssChannelData != null;
+    }
+
+    @Override
+    public MediaRssChannelData mediaRssChannelData() {
+        if (mediaRssChannelData == null) {
+            mediaRssChannelData = new MediaRssChannelDataImpl();
+        }
         return mediaRssChannelData;
     }
 
     @Override
-    public OpenSearchChannelData getOpenSearchChannelData() {
+    public boolean hasOpenSearchChannel() {
+        return openSearchChannelData != null;
+    }
+
+    @Override
+    public OpenSearchChannelData openSearchChannelData() {
+        if (openSearchChannelData == null) {
+            openSearchChannelData = new OpenSearchChannelDataImpl();
+        }
         return openSearchChannelData;
     }
 
     @Override
-    public PodcastChannelData getPodcastChannelData() {
+    public boolean hasPodcastChannel() {
+        return podcastChannelData != null;
+    }
+
+    @Override
+    public PodcastChannelData podcastChannelData() {
+        if (podcastChannelData == null) {
+            podcastChannelData = new PodcastChannelDataImpl();
+        }
         return podcastChannelData;
     }
 
     @Override
-    public SpotifyChannelData getSpotifyChannelData() {
+    public boolean hasSpotifyChannel() {
+        return spotifyChannelData != null;
+    }
+
+    @Override
+    public SpotifyChannelData spotifyChannelData() {
+        if (spotifyChannelData == null) {
+            spotifyChannelData = new SpotifyChannelDataImpl();
+        }
         return spotifyChannelData;
     }
 
     @Override
-    public YoutubeChannelData getYoutubeChannelData() {
+    public boolean hasYoutubeChannel() {
+        return youtubeChannelData != null;
+    }
+
+    @Override
+    public YoutubeChannelData youtubeChannelData() {
+        if (youtubeChannelData == null) {
+            youtubeChannelData = new YoutubeChannelDataImpl();
+        }
         return youtubeChannelData;
     }
 
@@ -93,11 +174,11 @@ public boolean equals(Object o) {
         if (!(o instanceof FeedChannelImpl)) return false;
         if (!super.equals(o)) return false;
         FeedChannelImpl that = (FeedChannelImpl) o;
-        return Objects.equals(getItunesChannelData(), that.getItunesChannelData()) && Objects.equals(getMediaRssChannelData(), that.getMediaRssChannelData()) && Objects.equals(getOpenSearchChannelData(), that.getOpenSearchChannelData()) && Objects.equals(getPodcastChannelData(), that.getPodcastChannelData()) && Objects.equals(getYoutubeChannelData(), that.getYoutubeChannelData());
+        return Objects.equals(itunesChannelData(), that.itunesChannelData()) && Objects.equals(mediaRssChannelData(), that.mediaRssChannelData()) && Objects.equals(openSearchChannelData(), that.openSearchChannelData()) && Objects.equals(podcastChannelData(), that.podcastChannelData()) && Objects.equals(youtubeChannelData(), that.youtubeChannelData());
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(super.hashCode(), getItunesChannelData(), getMediaRssChannelData(), getOpenSearchChannelData(), getPodcastChannelData(), getYoutubeChannelData());
+        return Objects.hash(super.hashCode(), itunesChannelData(), mediaRssChannelData(), openSearchChannelData(), podcastChannelData(), youtubeChannelData());
     }
 }