added some comments for how the metadata interface should be used.

core/src/zero1hd/rhythmbullet/audio/AudioMetadata.java

@@ -1,3 +1,9 @@
+/**
+ * Metadata for audio. Not thread-safe.
+ * @author yunya
+ *
+ */
+
 package zero1hd.rhythmbullet.audio;
 
 import com.badlogic.gdx.files.FileHandle;
@@ -5,23 +11,57 @@ import com.badlogic.gdx.graphics.Texture;
 import com.badlogic.gdx.utils.Disposable;
 
 public interface AudioMetadata extends Disposable {
-	
+	/**
+	 * Load the album art data in to memory.
+	 */
 	public void loadAlbumCover();
 	
+	/**
+	 * Unloads album art from memory.
+	 */
 	public void unloadAlbumCover();
 
+	/**
+	 * 
+	 * @return the author for the song in the metadata.
+	 */
 	public String getAuthor();
 	
+	/**
+	 * 
+	 * @return the length of the song with proper fomatting.
+	 */
 	public String getLength();
 	
+	/**
+	 * 
+	 * @return the texture. Needs to be loaded before hand or else will return null.
+	 */
 	public Texture getAlbumCover();
 	
+	/**
+	 * 
+	 * @return returns the genre of the song stored in metadata.
+	 */
 	public String getGenre();
 	
+	/**
+	 * 
+	 * @return the filehandle.
+	 */
 	public FileHandle getFileHandle();
 	
+	/**
+	 * 
+	 * @return the extra metadata for RhythmBullet.
+	 */
 	public RhythmBulletMetadata getRBMetadata();
 	
+	/**
+	 * This method effectively overwrites the mp3 file by creating a copy of it with the new metadata, and the deleting the old one, and renaming the new on to the old ones name.
+	 * This is the suggested way of doing things by the library author in this thread: https://github.com/mpatric/mp3agic/issues/69
+	 * @return true if succeeded in overwrite, and false if failed.
+	 */
 	public boolean flushRBMetadata();
 	
 	@Override

core/src/zero1hd/rhythmbullet/audio/MP3Metadata.java

@@ -119,7 +119,6 @@ public class MP3Metadata implements AudioMetadata {
 			fileHandle = Gdx.files.absolute(path);
 			return true;
 		} catch (UnsupportedTagException | InvalidDataException | IOException | NotSupportedException e) {
-			e.printStackTrace();
 			return false;
 		}
 	}