Resolves #694. Address null pointer when no system audio devices are available. (#695)

Co-authored-by: Denny <denny@denny-desktop>

src/main/java/io/github/dsheirer/audio/playback/AudioPlaybackManager.java

@@ -81,15 +81,23 @@ public class AudioPlaybackManager implements Listener<AudioSegment>, IAudioContr
         MyEventBus.getEventBus().register(this);
 
         MixerChannelConfiguration configuration = mUserPreferences.getPlaybackPreference().getMixerChannelConfiguration();
-        try
+
+        if(configuration != null)
         {
-            setMixerChannelConfiguration(configuration);
+            try
+            {
+                setMixerChannelConfiguration(configuration);
+            }
+            catch(AudioException ae)
+            {
+                mLog.error("Error during setup of audio playback configuration.  Attempted to use audio mixer [" +
+                    (configuration != null ? configuration.getMixer().toString() : "null") + "] and channel [" +
+                    (configuration != null ? configuration.getMixerChannel().name() : "null") + "]", ae);
+            }
         }
-        catch(AudioException ae)
+        else
         {
-            mLog.error("Error during setup of audio playback configuration.  Attempted to use audio mixer [" +
+            mLog.warn("No audio output devices available");
-                (configuration != null ? configuration.getMixer().toString() : "null") + "] and channel [" +
-                (configuration != null ? configuration.getMixerChannel().name() : "null") + "]", ae);
         }
     }
 

src/main/java/io/github/dsheirer/preference/playback/PlaybackPreference.java

@@ -350,19 +350,26 @@ public class PlaybackPreference extends Preference
         {
             MixerChannelConfiguration defaultConfig = MixerManager.getDefaultOutputMixer();
 
-            String configName = mPreferences.get(PREFERENCE_KEY_MIXER_CHANNEL_CONFIG, defaultConfig.toString());
+            if(defaultConfig != null)
-
-            for(MixerChannelConfiguration config: MixerManager.getOutputMixers())
             {
-                if(config.toString().contentEquals(configName))
+                String configName = mPreferences.get(PREFERENCE_KEY_MIXER_CHANNEL_CONFIG, defaultConfig.toString());
+
+                for(MixerChannelConfiguration config: MixerManager.getOutputMixers())
                 {
-                    mMixerChannelConfiguration = config;
+                    if(config.toString().contentEquals(configName))
+                    {
+                        mMixerChannelConfiguration = config;
+                    }
+                }
+
+                if(mMixerChannelConfiguration == null)
+                {
+                    mMixerChannelConfiguration = defaultConfig;
                 }
             }
-
+            else
-            if(mMixerChannelConfiguration == null)
             {
-                mMixerChannelConfiguration = defaultConfig;
+                mLog.error("Error - no system audio devices available");
             }
         }
 

src/main/java/io/github/dsheirer/record/AudioRecordingManager.java

@@ -105,6 +105,19 @@ public class AudioRecordingManager implements Listener<AudioSegment>
      */
     public void processCompletedAudioSegment(AudioSegment audioSegment)
     {
+        //Debug
+        if(audioSegment.getAudioBufferCount() == 0)
+        {
+            mLog.debug("Audio Segment detected with 0 audio buffers");
+        }
+
+        List<Identifier> toIdentifiers = audioSegment.getIdentifierCollection().getIdentifiers(Role.TO);
+
+        if(toIdentifiers.isEmpty())
+        {
+            mLog.debug("Audio Segment detected with NO TO identifiers");
+        }
+
         if(audioSegment.recordAudioProperty().get())
         {
             mCompletedAudioSegmentQueue.add(audioSegment);