Add a FunctionalLoadResultHandler and examples

Author: duncte123

README.md

@@ -129,7 +129,7 @@ Alternatively, you can use `Discord4JUtils.leave(gatewayClient, guildId);` as th
 The following examples are minimal implementations but show how the library works.
 - Java examples
   - JDA (simple): [link](src/test/java/JavaJDAExample.java)
-  - JDA (more complex example): [link](testbot/src/main/java/me/duncte123/testbot/Main.java)
+  - JDA (more real-world like example): [link](testbot/src/main/java/me/duncte123/testbot/Main.java)
 - Kotlin examples
   - JDA: [link](src/test/kotlin/testScript.kt)
   - Discord4J: [link](src/test/kotlin/d4jTestScript.kt)
@@ -165,6 +165,6 @@ public void onDiscordVoiceServerUpdate(VoiceServerUpdateEvent event) {
     Link link = lavalink.getLink(event.getGuildId(), region);
 
     // Finally, tell lavalink to connect.
-    link.onVoiceServerUpdate(lavalinkVoiceState)
+    link.onVoiceServerUpdate(lavalinkVoiceState);
 }
 ```

src/main/kotlin/dev/arbjerg/lavalink/client/FunctionalLoadResultHandler.kt

@@ -0,0 +1,45 @@
+package dev.arbjerg.lavalink.client
+
+import dev.arbjerg.lavalink.client.protocol.LoadFailed
+import dev.arbjerg.lavalink.client.protocol.PlaylistLoaded
+import dev.arbjerg.lavalink.client.protocol.SearchResult
+import dev.arbjerg.lavalink.client.protocol.TrackLoaded
+import java.util.function.Consumer
+
+/**
+ * Helper class for creating an [AbstractAudioLoadResultHandler] using only methods that can be passed as lambdas.
+ *
+ * @param trackLoadedConsumer gets called when a track has loaded
+ * @param playlistLoadedConsumer gets called when a playlist has loaded
+ * @param searchResultConsumer gets called when a search result has loaded
+ * @param noMatchesHandler gets called when there are no matches for your input
+ * @param loadFailedConsumer gets called in case of a load failure
+ */
+class FunctionalLoadResultHandler @JvmOverloads constructor(
+    private val trackLoadedConsumer: Consumer<TrackLoaded>?,
+    private val playlistLoadedConsumer: Consumer<PlaylistLoaded>? = null,
+    private val searchResultConsumer: Consumer<SearchResult>? = null,
+    private val noMatchesHandler: Runnable? = null,
+    private val loadFailedConsumer: Consumer<LoadFailed>? = null,
+) : AbstractAudioLoadResultHandler() {
+
+    override fun ontrackLoaded(result: TrackLoaded) {
+        trackLoadedConsumer?.accept(result)
+    }
+
+    override fun onPlaylistLoaded(result: PlaylistLoaded) {
+        playlistLoadedConsumer?.accept(result)
+    }
+
+    override fun onSearchResultLoaded(result: SearchResult) {
+        searchResultConsumer?.accept(result)
+    }
+
+    override fun noMatches() {
+        noMatchesHandler?.run()
+    }
+
+    override fun loadFailed(result: LoadFailed) {
+        loadFailedConsumer?.accept(result)
+    }
+}

src/test/java/JavaJDAExample.java

@@ -177,13 +177,13 @@ public void onSlashCommandInteraction(@NotNull SlashCommandInteractionEvent even
                 final long guildId = guild.getIdLong();
                 final Link link = this.client.getLink(guildId);
 
-                link.loadItem(identifier).subscribe(new AbstractAudioLoadResultHandler() {
-                    @Override
-                    public void ontrackLoaded(@NotNull TrackLoaded result) {
-                        final Track track = result.getTrack();
+                link.loadItem(identifier).subscribe(new FunctionalLoadResultHandler(
+                    // Track loaded
+                    (trackLoad) -> {
+                        final Track track = trackLoad.getTrack();
 
                         // Inner class at the end of this file
-                        var userData = new MyUserData(event.getUser().getIdLong());
+                        final var userData = new MyUserData(event.getUser().getIdLong());
 
                         track.setUserData(userData);
 
@@ -212,19 +212,11 @@ public void ontrackLoaded(@NotNull TrackLoaded result) {
                                     event.getHook().sendMessage("Now playing: " + trackTitle + "\nRequested by: <@" + customData.requester() + '>').queue();
                                 });
                         }
-                    }
-
-                    @Override
-                    public void onPlaylistLoaded(@NotNull PlaylistLoaded result) {
-                        final int trackCount = result.getTracks().size();
-                        event.getHook()
-                            .sendMessage("This playlist has " + trackCount + " tracks!")
-                            .queue();
-                    }
-
-                    @Override
-                    public void onSearchResultLoaded(@NotNull SearchResult result) {
-                        final List<Track> tracks = result.getTracks();
+                    },
+                    null, // playlist loaded
+                    // search result loaded
+                    (search) -> {
+                        final List<Track> tracks = search.getTracks();
 
                         if (tracks.isEmpty()) {
                             event.getHook().sendMessage("No tracks found!").queue();
@@ -239,18 +231,10 @@ public void onSearchResultLoaded(@NotNull SearchResult result) {
                             .subscribe((ignored) -> {
                                 event.getHook().sendMessage("Now playing: " + firstTrack.getInfo().getTitle()).queue();
                             });
-                    }
-
-                    @Override
-                    public void noMatches() {
-                        event.getHook().sendMessage("No matches found for your input!").queue();
-                    }
-
-                    @Override
-                    public void loadFailed(@NotNull LoadFailed result) {
-                        event.getHook().sendMessage("Failed to load track! " + result.getException().getMessage()).queue();
-                    }
-                });
+                    },
+                    null, // no matches
+                    null // load failed
+                ));
 
                 break;
             }