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 (file)
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 (file)
--- 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 (file)
--- 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"));
        }
 
 }