X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Fnet%2Fpterodactylus%2Fsonitus%2Fio%2FOggVorbisIdentifier.java;h=49daa2780459842a858d51a35881450a79864418;hb=00af65503a2076371291ce8e019da2546458bdac;hp=64ad2ddab94f6c3058d681e5b28bb9130541937c;hpb=3b99111c3d082841f0a7f5819103fb3db6ba8447;p=sonitus.git

diff --git a/src/main/java/net/pterodactylus/sonitus/io/OggVorbisIdentifier.java b/src/main/java/net/pterodactylus/sonitus/io/OggVorbisIdentifier.java
index 64ad2dd..49daa27 100644
--- a/src/main/java/net/pterodactylus/sonitus/io/OggVorbisIdentifier.java
+++ b/src/main/java/net/pterodactylus/sonitus/io/OggVorbisIdentifier.java
@@ -22,6 +22,7 @@ import java.io.InputStream;
 
 import net.pterodactylus.sonitus.data.Format;
 
+import com.google.common.base.Optional;
 import com.jcraft.jogg.Packet;
 import com.jcraft.jogg.Page;
 import com.jcraft.jogg.StreamState;
@@ -30,7 +31,9 @@ import com.jcraft.jorbis.Comment;
 import com.jcraft.jorbis.Info;
 
 /**
- * Identifies Ogg Vorbis files.
+ * Identifies Ogg Vorbis files. <p> All knowledge used in this class has been
+ * taken from <a href="http://www.jcraft.com/jorbis/tutorial/Tutorial.html">jcraft.com/jorbis/tutorial/Tutorial.html</a>.
+ * </p>
  *
  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  */
@@ -49,10 +52,13 @@ public class OggVorbisIdentifier {
 	 * Format} describing the stream.
 	 *
 	 * @param inputStream
-	 * @return
+	 * 		The input stream to identify as Ogg Vorbis
+	 * @return The identified format, or {@link com.google.common.base.Optional#absent()}
+	 *         if the stream could not be identified
 	 * @throws IOException
+	 * 		if an I/O error occurs
 	 */
-	public static Format identify(InputStream inputStream) throws IOException {
+	public static Optional<Format> identify(InputStream inputStream) throws IOException {
 
 		/* stuff needed to decode Ogg. */
 		Packet packet = new Packet();
@@ -79,7 +85,7 @@ public class OggVorbisIdentifier {
 			syncState.wrote(read);
 			switch (syncState.pageout(page)) {
 				case -1:
-					throw new IOException("Hole in Ogg data!");
+					return Optional.absent();
 				case 1:
 					if (!streamStateInitialized) {
 						/* init stream state. */
@@ -90,11 +96,11 @@ public class OggVorbisIdentifier {
 						streamStateInitialized = true;
 					}
 					if (streamState.pagein(page) == -1) {
-						throw new IOException("Error parsing Ogg data!");
+						return Optional.absent();
 					}
 					switch (streamState.packetout(packet)) {
 						case -1:
-							throw new IOException("Error parsing Ogg data!");
+							return Optional.absent();
 						case 1:
 							info.synthesis_headerin(comment, packet);
 							packetsRead++;
@@ -109,7 +115,7 @@ public class OggVorbisIdentifier {
 			buffer = syncState.data;
 		}
 
-		return new Format(info.channels, info.rate, "Vorbis");
+		return Optional.of(new Format(info.channels, info.rate, "Vorbis"));
 	}
 
 }