Fix Exception thrown opening folder in "Playlist Directory"

src/main/java/listfix/comparators/DirectoryThenFileThenAlphabeticalFileComparator.java

@@ -22,27 +22,12 @@
 
 import java.io.File;
 
-/*
-============================================================================
-= Author:   Jeremy Caron
-= File:     DirectoryThenFileThenAlphabeticalFileComparator.java
-= Purpose:  Sorts directories ahead of files, and then sorts files
-=      alphabetically (ignoring case).
-============================================================================
- */
-
 /**
- *
- * @author jcaron
+ * Sorts directories ahead of files, and then sorts files alphabetically (ignoring case).
  */
 public class DirectoryThenFileThenAlphabeticalFileComparator implements java.util.Comparator<File>
 {
-  /**
-   *
-   * @param a
-   * @param b
-   * @return
-   */
+
   @Override
   public int compare(File a, File b)
   {

src/main/java/listfix/util/FileTypeSearch.java

@@ -1,23 +1,3 @@
-/*
- * listFix() - Fix Broken Playlists!
- * Copyright (C) 2001-2014 Jeremy Caron
- *
- * This file is part of listFix().
- *
- * 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 2
- * 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, please see http://www.gnu.org/licenses/
- */
-
 package listfix.util;
 
 import listfix.comparators.DirectoryThenFileThenAlphabeticalFileComparator;
@@ -29,14 +9,9 @@
 import java.util.Collections;
 import java.util.List;
 
-/**
- *
- * @author jcaron
- */
 public class FileTypeSearch
 {
   /**
-   *
    * @param directoryToSearch
    * @param filter
    * @return
@@ -45,32 +20,27 @@ public List<File> findFiles(File directoryToSearch, FileFilter filter)
   {
     if (directoryToSearch.exists())
     {
-      List<File> ol = new ArrayList<>();
       File[] inodes = directoryToSearch.listFiles(filter);
 
       if (inodes != null && inodes.length > 0)
       {
-                ol.addAll(Arrays.asList(inodes));
-        Collections.sort(ol, new DirectoryThenFileThenAlphabeticalFileComparator());
-        File f;
+        List<File> ol = new ArrayList<>(Arrays.asList(inodes));
+        ol.sort(new DirectoryThenFileThenAlphabeticalFileComparator());
         List<File> files = new ArrayList<>();
-        for (File ol1 : ol)
+        for (File file : ol)
         {
-          f = ol1;
-          if (f.isDirectory())
+          if (file.isDirectory())
           {
-            files.addAll(findFiles(f, filter));
+            files.addAll(findFiles(file, filter));
           }
           else
           {
-            files.add(f);
+            files.add(file);
           }
         }
-
         return files;
       }
-      return null;
     }
-    return null;
+    return Collections.emptyList();
   }
 }

src/main/java/listfix/view/GUIScreen.java

@@ -1447,7 +1447,7 @@ private void openIconButtonActionPerformed(java.awt.event.ActionEvent evt)//GEN-
   private void openPlaylistFoldersFromPlaylistTree()
   {
     this.getSelectedFilesFromTreePlaylists().stream()
-      .map(File :: getParentFile)
+      .map(file -> file.isDirectory() ? file : file.getParentFile())
       .filter(Objects :: nonNull)
       .distinct()
       .forEach(this :: openFolderInExplorerPerformed);