Added logging of how many files were supposed to be opened and how ma…

…ny failed.

app/src/main/java/com/oracle/javafx/scenebuilder/app/SceneBuilderApp.java

@@ -735,6 +735,7 @@ private FileOpenResult performOpenFiles(List<File> fxmlFiles) {
         assert fxmlFiles != null;
         assert fxmlFiles.isEmpty() == false;
 
+        LOGGER.log(Level.FINE, "Opening {0} files...", fxmlFiles.size());
         final Map<File, Exception> exceptions = new HashMap<>();
         final List<File> openedFiles = new ArrayList<>();
         for (File fxmlFile : fxmlFiles) {
@@ -764,7 +765,11 @@ private FileOpenResult performOpenFiles(List<File> fxmlFiles) {
             final PreferencesController pc = PreferencesController.getSingleton();
             pc.getRecordGlobal().addRecentItems(openedFiles);
         }
-
+        if (exceptions.size() > 0) {
+            LOGGER.log(Level.WARNING, "Failed to open {0} of {1} files!", new Object[] {exceptions.size(), fxmlFiles.size()});
+        } else {
+            LOGGER.log(Level.FINE, "Successfully opened all files.");
+        }
         return new FileOpenResult(fxmlFiles, exceptions);
     }