Added javadocs for Playlist

Author: koca2000

src/main/java/com/xxmicloxx/NoteBlockAPI/model/Playlist.java

@@ -11,6 +11,10 @@ public Playlist(Song ...songs){
 		this.songs.addAll(Arrays.asList(songs));
 	}
 
+	/**
+	 * Add array of {@link Song} to playlist
+	 * @param songs
+	 */
 	public void add(Song ...songs){
 		this.songs.addAll(Arrays.asList(songs));
 	}
@@ -31,19 +35,38 @@ public void remove(Song ...songs){
 		}
 	}
 
+	/**
+	 * Get {@link Song} in playlist at specified index
+	 * @param songNumber - song index
+	 * @return
+	 */
 	public Song get(int songNumber){
 		return songs.get(songNumber);
 	}
 
+	/**
+	 * Get number of {@link Song} in playlist
+	 * @return
+	 */
 	public int getCount(){
 		return songs.size();
 	}
 
+	/**
+	 * Check whether {@link Song} is not last in playlist
+	 * @param songNumber
+	 * @return true if there is another {@link Song} after specified index
+	 */
 	public boolean hasNext(int songNumber){
 		return songs.size() > (songNumber + 1);
 	}
 
-	public boolean exits(int songNumber){
+	/**
+	 * Check whether {@link Song} with specified index exists in playlist
+	 * @param songNumber
+	 * @return
+	 */
+	public boolean exist(int songNumber){
 		return songs.size() > songNumber;
 	}
 }

src/main/java/com/xxmicloxx/NoteBlockAPI/songplayer/SongPlayer.java

@@ -594,14 +594,23 @@ public Playlist getPlaylist() {
 		return playlist;
 	}
 
+	/**
+	 * Get index of actually played {@link Song} in {@link Playlist}
+	 * @return
+	 */
 	public int getPlayedSongIndex(){
 		return actualSong;
 	}
 
+	/**
+	 * Start playing {@link Song} at specified index in {@link Playlist}
+	 * If there is no {@link Song} at this index, {@link SongPlayer} will continue playing current song
+	 * @param index
+	 */
 	public void playSong(int index){
 		lock.lock();
 		try {
-			if (playlist.exits(index)){
+			if (playlist.exist(index)){
 				song = playlist.get(index);
 				actualSong = index;
 				tick = -1;