Fix for issue 6966: open all files of multiple entries

CHANGELOG.md

@@ -22,6 +22,7 @@ Note that this project **does not** adhere to [Semantic Versioning](http://semve
 - We added a feature that allows the user to copy highlighted text in the preview window. [#6962](https://github.com/JabRef/jabref/issues/6962)
 - We added a feature that allows you to create new BibEntry via paste arxivId [#2292](https://github.com/JabRef/jabref/issues/2292)
 - We added a feature that allows the user to choose whether to trust the target site when unable to find a valid certification path from the file download site. [#7616](https://github.com/JabRef/jabref/issues/7616)
+- We added a feature that allows the user to open all linked files of multiple selected entries by "Open file" option. [#6966](https://github.com/JabRef/jabref/issues/6966)
 - We added a keybinding preset for new entries. [#7705](https://github.com/JabRef/jabref/issues/7705)
 
 ### Changed

src/main/java/org/jabref/gui/actions/ActionHelper.java

@@ -81,6 +81,39 @@ public static BooleanExpression isFilePresentForSelectedEntry(StateManager state
         return BooleanExpression.booleanExpression(fileIsPresent);
     }
 
+    /**
+     * Check if at least one of the selected entries has linked files
+     * <br>
+     * Used in {@link org.jabref.gui.maintable.OpenExternalFileAction} when multiple entries selected
+     * @param stateManager manager for the state of the GUI
+     * @param preferencesService services of preferences
+     * @return a boolean binding
+     */
+    public static BooleanExpression hasPresentFileForSelectedEntries(StateManager stateManager, PreferencesService preferencesService) {
+        return Bindings.createBooleanBinding(() -> {
+            ObservableList<BibEntry> selectedEntries = stateManager.getSelectedEntries();
+            List<LinkedFile> files;
+            for (BibEntry entry:selectedEntries) {
+                files = entry.getFiles();
+
+                if ((entry.getFiles().size() > 0) && stateManager.getActiveDatabase().isPresent()) {
+                    if (files.get(0).isOnlineLink()) {
+                        return true;
+                    }
+
+                    Optional<Path> filename = FileHelper.find(
+                            stateManager.getActiveDatabase().get(),
+                            files.get(0).getLink(),
+                            preferencesService.getFilePreferences());
+                    if (filename.isPresent()) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        });
+    }
+
     public static BooleanExpression isOpenMultiDatabase(TabPane tabbedPane) {
         return Bindings.size(tabbedPane.getTabs()).greaterThan(1);
     }

src/main/java/org/jabref/gui/maintable/OpenExternalFileAction.java

@@ -1,5 +1,6 @@
 package org.jabref.gui.maintable;
 
+import java.util.LinkedList;
 import java.util.List;
 
 import org.jabref.gui.DialogService;
@@ -9,7 +10,6 @@
 import org.jabref.gui.actions.SimpleCommand;
 import org.jabref.gui.externalfiletype.ExternalFileTypes;
 import org.jabref.gui.fieldeditors.LinkedFileViewModel;
-import org.jabref.logic.l10n.Localization;
 import org.jabref.model.entry.BibEntry;
 import org.jabref.preferences.PreferencesService;
 
@@ -24,32 +24,41 @@ public OpenExternalFileAction(DialogService dialogService, StateManager stateMan
         this.stateManager = stateManager;
         this.preferencesService = preferencesService;
 
-        this.executable.bind(ActionHelper.isFilePresentForSelectedEntry(stateManager, preferencesService)
-                                         .and(ActionHelper.needsEntriesSelected(1, stateManager)));
+        this.executable.bind(ActionHelper.hasPresentFileForSelectedEntries(stateManager, preferencesService)
+                .and(ActionHelper.needsEntriesSelected(stateManager))
+        );
     }
 
+    /**
+     * Open all linked files of the selected entries.
+     * <br>
+     * If some selected entries have linked file and others do not, ignore the latter.
+     */
     @Override
     public void execute() {
         stateManager.getActiveDatabase().ifPresent(databaseContext -> {
             final List<BibEntry> selectedEntries = stateManager.getSelectedEntries();
 
-            if (selectedEntries.size() != 1) {
-                dialogService.notify(Localization.lang("This operation requires exactly one item to be selected."));
-                return;
+            List<LinkedFileViewModel> linkedFileViewModelList = new LinkedList<>();
+            LinkedFileViewModel linkedFileViewModel;
+
+            for (BibEntry entry:selectedEntries) {
+                if (!entry.getFiles().isEmpty()) {
+                    linkedFileViewModel = new LinkedFileViewModel(
+                            entry.getFiles().get(0),
+                            entry,
+                            databaseContext,
+                            Globals.TASK_EXECUTOR,
+                            dialogService,
+                            preferencesService.getXmpPreferences(),
+                            preferencesService.getFilePreferences(),
+                            ExternalFileTypes.getInstance());
+
+                    linkedFileViewModelList.add(linkedFileViewModel);
+                }
             }
 
-            final BibEntry entry = selectedEntries.get(0);
-
-            LinkedFileViewModel linkedFileViewModel = new LinkedFileViewModel(
-                    entry.getFiles().get(0),
-                    entry,
-                    databaseContext,
-                    Globals.TASK_EXECUTOR,
-                    dialogService,
-                    preferencesService.getXmpPreferences(),
-                    preferencesService.getFilePreferences(),
-                    ExternalFileTypes.getInstance());
-            linkedFileViewModel.open();
+            linkedFileViewModelList.forEach(LinkedFileViewModel::open);
         });
     }
 }