Fix for unlinked file importer that did not import all importable files (#8444)

CHANGELOG.md

@@ -33,6 +33,7 @@ Note that this project **does not** adhere to [Semantic Versioning](http://semve
 - We fixed an issue when reading non-UTF-8 encoded. When no encoding header is present, the encoding is now detected from the file content (and the preference option is disregarded) [#8417](https://github.com/JabRef/jabref/issues/8417)
 - We fixed an issue where pasting a URL was replacing + signs by spaces making the URL unreachable. [#8448](https://github.com/JabRef/jabref/issues/8448)
 - We fixed an issue where creating subsidiary files from aux files created with some versions of biblatex would produce incorrect results. [#8513](https://github.com/JabRef/jabref/issues/8513)
+- We fixed an issue where not all found unlinked local files were imported correctly due to some race condition. [#8444](https://github.com/JabRef/jabref/issues/8444)
 
 ### Removed
 

src/main/java/org/jabref/gui/externalfiles/ImportHandler.java

@@ -68,26 +68,25 @@ public ExternalFilesEntryLinker getLinker() {
         return linker;
     }
 
-    public BackgroundTask<List<ImportFilesResultItemViewModel>> importFilesInBackground(List<Path> files) {
+    public BackgroundTask<List<ImportFilesResultItemViewModel>> importFilesInBackground(final List<Path> files) {
         return new BackgroundTask<>() {
             private int counter;
-            private List<BibEntry> entriesToAdd;
             private final List<ImportFilesResultItemViewModel> results = new ArrayList<>();
 
             @Override
             protected List<ImportFilesResultItemViewModel> call() {
                 counter = 1;
                 CompoundEdit ce = new CompoundEdit();
-                for (Path file: files) {
-                    entriesToAdd = Collections.emptyList();
+                for (final Path file : files) {
+                    final List<BibEntry> entriesToAdd = new ArrayList<>();
 
                     if (isCanceled()) {
                         break;
                     }
 
                     DefaultTaskExecutor.runInJavaFXThread(() -> {
                         updateMessage(Localization.lang("Processing file %0", file.getFileName()));
-                        updateProgress(counter, files.size() - 1);
+                        updateProgress(counter, files.size() - 1d);
                     });
 
                     try {
@@ -100,10 +99,10 @@ protected List<ImportFilesResultItemViewModel> call() {
                             }
 
                             if (!pdfEntriesInFile.isEmpty()) {
-                                entriesToAdd = pdfEntriesInFile;
+                                entriesToAdd.addAll(pdfEntriesInFile);
                                 addResultToList(file, true, Localization.lang("Importing using extracted PDF data"));
                             } else {
-                                entriesToAdd = Collections.singletonList(createEmptyEntryWithLink(file));
+                                entriesToAdd.add(createEmptyEntryWithLink(file));
                                 addResultToList(file, false, Localization.lang("No metadata found. Creating empty entry with file link"));
                             }
                         } else if (FileUtil.isBibFile(file)) {
@@ -112,10 +111,10 @@ protected List<ImportFilesResultItemViewModel> call() {
                                 addResultToList(file, false, bibtexParserResult.getErrorMessage());
                             }
 
-                            entriesToAdd = bibtexParserResult.getDatabaseContext().getEntries();
+                            entriesToAdd.addAll(bibtexParserResult.getDatabaseContext().getEntries());
                             addResultToList(file, false, Localization.lang("Importing bib entry"));
                         } else {
-                            entriesToAdd = Collections.singletonList(createEmptyEntryWithLink(file));
+                            entriesToAdd.add(createEmptyEntryWithLink(file));
                             addResultToList(file, false, Localization.lang("No BibTeX data found. Creating empty entry with file link"));
                         }
                     } catch (IOException ex) {