From: David ‘Bombe’ Roden <bombe@pterodactylus.net>
Date: Thu, 14 Mar 2013 21:40:24 +0000 (+0100)
Subject: Return an optional instead of throwing an exception.
X-Git-Url: https://git.pterodactylus.net/?a=commitdiff_plain;h=d0f12db4a8fe02601743e4b23618d44e193fd474;p=sonitus.git

Return an optional instead of throwing an exception.
---

diff --git a/src/main/java/net/pterodactylus/sonitus/io/IdentifierException.java b/src/main/java/net/pterodactylus/sonitus/io/IdentifierException.java
deleted file mode 100644
index e6c03f6..0000000
--- a/src/main/java/net/pterodactylus/sonitus/io/IdentifierException.java
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
- * Sonitus - IdentifierException.java - Copyright © 2013 David Roden
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-package net.pterodactylus.sonitus.io;
-
-import java.io.IOException;
-
-/**
- * Exception that signals that a stream could not be identified by {@link
- * IdentifyingInputStream}.
- *
- * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
- */
-public class IdentifierException extends IOException {
-
-	/** Creates a new identifier exception. */
-	public IdentifierException() {
-		super();
-	}
-
-	/**
-	 * Creates a new identifier exception.
-	 *
-	 * @param message
-	 * 		The message of the exception
-	 */
-	public IdentifierException(String message) {
-		super(message);
-	}
-
-	/**
-	 * Creates a new identifier exception.
-	 *
-	 * @param cause
-	 * 		The root cause of the exception
-	 */
-	public IdentifierException(Throwable cause) {
-		super(cause);
-	}
-
-	/**
-	 * Creates a new identifier exception.
-	 *
-	 * @param message
-	 * 		The message of the exception
-	 * @param cause
-	 * 		The root cause of the exception
-	 */
-	public IdentifierException(String message, Throwable cause) {
-		super(message, cause);
-	}
-
-}
diff --git a/src/main/java/net/pterodactylus/sonitus/io/IdentifyingInputStream.java b/src/main/java/net/pterodactylus/sonitus/io/IdentifyingInputStream.java
index 537c9a4..7cc69b0 100644
--- a/src/main/java/net/pterodactylus/sonitus/io/IdentifyingInputStream.java
+++ b/src/main/java/net/pterodactylus/sonitus/io/IdentifyingInputStream.java
@@ -83,11 +83,9 @@ public class IdentifyingInputStream extends FilterInputStream {
 		RememberingInputStream rememberingInputStream = new RememberingInputStream(inputStream);
 
 		/* try Ogg Vorbis first. */
-		try {
-			Format format = OggVorbisIdentifier.identify(rememberingInputStream);
-			return Optional.of(new IdentifyingInputStream(rememberingInputStream.remembered(), format));
-		} catch (IdentifierException ie1) {
-			rememberingInputStream = new RememberingInputStream(rememberingInputStream.remembered());
+		Optional<Format> format = OggVorbisIdentifier.identify(rememberingInputStream);
+		if (format.isPresent()) {
+			return Optional.of(new IdentifyingInputStream(rememberingInputStream.remembered(), format.get()));
 		}
 
 		return Optional.absent();
diff --git a/src/main/java/net/pterodactylus/sonitus/io/OggVorbisIdentifier.java b/src/main/java/net/pterodactylus/sonitus/io/OggVorbisIdentifier.java
index ab732b8..d889b97 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;
@@ -49,10 +50,13 @@ 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 +83,7 @@ public class OggVorbisIdentifier {
 			syncState.wrote(read);
 			switch (syncState.pageout(page)) {
 				case -1:
-					throw new IdentifierException("Hole in Ogg data!");
+					return Optional.absent();
 				case 1:
 					if (!streamStateInitialized) {
 						/* init stream state. */
@@ -90,11 +94,11 @@ public class OggVorbisIdentifier {
 						streamStateInitialized = true;
 					}
 					if (streamState.pagein(page) == -1) {
-						throw new IdentifierException("Error parsing Ogg data!");
+						return Optional.absent();
 					}
 					switch (streamState.packetout(packet)) {
 						case -1:
-							throw new IdentifierException("Error parsing Ogg data!");
+							return Optional.absent();
 						case 1:
 							info.synthesis_headerin(comment, packet);
 							packetsRead++;
@@ -109,7 +113,7 @@ public class OggVorbisIdentifier {
 			buffer = syncState.data;
 		}
 
-		return new Format(info.channels, info.rate, "Vorbis");
+		return Optional.of(new Format(info.channels, info.rate, "Vorbis"));
 	}
 
 }