Resolves #678 AudioChannelPanel threading issue. (#679)

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

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

@@ -52,6 +52,8 @@ import java.awt.EventQueue;
 import java.awt.Font;
 import java.util.Collections;
 import java.util.List;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
 
 public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, SettingChangeListener
 {
@@ -84,6 +86,7 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
     private Identifier mIdentifier;
     private List<Alias> mAliases = Collections.EMPTY_LIST;
     private AliasModel mAliasModel;
+    private Lock mLock = new ReentrantLock();
 
     public AudioChannelPanel(IconManager iconManager, UserPreferences userPreferences, SettingsManager settingsManager,
                              AudioOutput audioOutput, AliasModel aliasModel)
@@ -199,13 +202,24 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
      */
     private void resetLabels()
     {
-        boolean updated = mIdentifier != null;
+        //Protect access to mIdentifier and mAliases
-        mIdentifier = null;
+        mLock.lock();
-        mAliases = Collections.EMPTY_LIST;
 
-        if(updated)
+        try
         {
-            updateLabels();
+            boolean updated = mIdentifier != null;
+            mIdentifier = null;
+            mAliases = Collections.EMPTY_LIST;
+
+            //Hold the lock through the label update
+            if(updated)
+            {
+                updateLabels();
+            }
+        }
+        finally
+        {
+            mLock.unlock();
         }
     }
 
@@ -227,11 +241,28 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
 
         boolean updated = false;
 
-        if(toIds.size() == 1)
+        //Protect access to mIdentifier and mAliases
-        {
+        mLock.lock();
-            Identifier currentIdentifier = mIdentifier;
 
-            if(currentIdentifier == null || currentIdentifier != toIds.get(0))
+        try
+        {
+            if(toIds.size() == 1)
+            {
+                Identifier currentIdentifier = mIdentifier;
+
+                if(currentIdentifier == null || currentIdentifier != toIds.get(0))
+                {
+                    mIdentifier = toIds.get(0);
+                    AliasList aliasList = mAliasModel.getAliasList(identifierCollection);
+
+                    if(aliasList != null)
+                    {
+                        mAliases = aliasList.getAliases(mIdentifier);
+                    }
+                    updated = true;
+                }
+            }
+            else
             {
                 mIdentifier = toIds.get(0);
                 AliasList aliasList = mAliasModel.getAliasList(identifierCollection);
@@ -242,69 +273,64 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
                 }
                 updated = true;
             }
-        }
-        else
-        {
-            mIdentifier = toIds.get(0);
-            AliasList aliasList = mAliasModel.getAliasList(identifierCollection);
 
-            if(aliasList != null)
+            //Hold the lock through the label update
+            if(updated)
             {
-                mAliases = aliasList.getAliases(mIdentifier);
+                updateLabels();
             }
-            updated = true;
         }
-
+        finally
-        if(updated)
         {
-            updateLabels();
+            mLock.unlock();
         }
     }
 
     /**
-     * Updates the alias label with text and icon from the alias.  Note: this
+     * Updates the alias label with text and icon from the alias.
-     * does not occur on the Swing event thread -- wrap any calls to this
-     * method with an event thread call.
      */
     private void updateLabels()
     {
         String identifier = null;
         String iconName = null;
 
-        if(mAliases.size() == 1)
+        //Protect access to mIdentifier and mAliases
-        {
+        mLock.lock();
-            identifier = mAliases.get(0).getName();
-            iconName = mAliases.get(0).getIconName();
-        }
-        else if(mAliases.size() > 1)
-        {
-            identifier = Joiner.on(", ").skipNulls().join(mAliases);
-        }
 
-        if(identifier == null && mIdentifier != null)
+        try
         {
-            identifier = mTalkgroupFormatPreference.format(mIdentifier);
+            if(mAliases.size() == 1)
-        }
-
-        if(identifier == null)
-        {
-            identifier = "-----";
-        }
-
-        final ImageIcon icon = iconName != null ? mIconManager.getIcon(iconName, 18) : null;
-
-        final String identifierText = identifier;
-
-        EventQueue.invokeLater(new Runnable()
-        {
-            @Override
-            public void run()
             {
+                identifier = mAliases.get(0).getName();
+                iconName = mAliases.get(0).getIconName();
+            }
+            else if(mAliases.size() > 1)
+            {
+                identifier = Joiner.on(", ").skipNulls().join(mAliases);
+            }
+
+            if(identifier == null && mIdentifier != null)
+            {
+                identifier = mTalkgroupFormatPreference.format(mIdentifier);
+            }
+
+            if(identifier == null)
+            {
+                identifier = "-----";
+            }
+
+            final ImageIcon icon = iconName != null ? mIconManager.getIcon(iconName, 18) : null;
+            final String identifierText = identifier;
+
+            EventQueue.invokeLater(() -> {
                 mIdentifierLabel.setText(identifierText);
                 mIconLabel.setIcon(icon);
-            }
+            });
-        });
+        }
-
+        finally
+        {
+            mLock.unlock();
+        }
     }
 
     /**
@@ -329,14 +355,16 @@ public class AudioChannelPanel extends JPanel implements Listener<AudioEvent>, S
             switch(colorSetting.getColorSettingName())
             {
                 case CHANNEL_STATE_LABEL_DECODER:
-                    if(mIdentifierLabel != null)
+                    EventQueue.invokeLater(() -> {
-                    {
+                        if(mIdentifierLabel != null)
-                        mIdentifierLabel.setForeground(mLabelColor);
+                        {
-                    }
+                            mIdentifierLabel.setForeground(mLabelColor);
-                    if(mIconLabel != null)
+                        }
-                    {
+                        if(mIconLabel != null)
-                        mIconLabel.setForeground(mLabelColor);
+                        {
-                    }
+                            mIconLabel.setForeground(mLabelColor);
+                        }
+                    });
                     break;
                 default:
                     break;