Added Locale.ROOT to toUpper/toLower Methods

src/main/java/org/jabref/gui/BasePanel.java

@@ -21,6 +21,7 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
@@ -1104,7 +1105,7 @@ public BibEntry newEntry(EntryType type) {
 
                 // Create an UndoableInsertEntry object.
                 getUndoManager().addEdit(new UndoableInsertEntry(bibDatabaseContext.getDatabase(), be, BasePanel.this));
-                output(Localization.lang("Added new '%0' entry.", actualType.getName().toLowerCase()));
+                output(Localization.lang("Added new '%0' entry.", actualType.getName().toLowerCase(Locale.ROOT)));
 
                 // We are going to select the new entry. Before that, make sure that we are in
                 // show-entry mode. If we aren't already in that mode, enter the WILL_SHOW_EDITOR

src/main/java/org/jabref/gui/GenFieldsCustomizer.java

@@ -6,6 +6,7 @@
 import java.awt.GridBagLayout;
 import java.awt.Insets;
 import java.awt.event.ActionEvent;
+import java.util.Locale;
 
 import javax.swing.AbstractAction;
 import javax.swing.ActionMap;
@@ -131,7 +132,7 @@ private void okActionPerformed() {
             }
 
             Globals.prefs.put((JabRefPreferences.CUSTOM_TAB_NAME + i), parts[0]);
-            Globals.prefs.put((JabRefPreferences.CUSTOM_TAB_FIELDS + i), parts[1].toLowerCase());
+            Globals.prefs.put((JabRefPreferences.CUSTOM_TAB_FIELDS + i), parts[1].toLowerCase(Locale.ROOT));
         }
         Globals.prefs.purgeSeries(JabRefPreferences.CUSTOM_TAB_NAME, i);
         Globals.prefs.purgeSeries(JabRefPreferences.CUSTOM_TAB_FIELDS, i);

src/main/java/org/jabref/gui/ReplaceStringDialog.java

@@ -6,6 +6,7 @@
 import java.awt.Insets;
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
+import java.util.Locale;
 
 import javax.swing.AbstractAction;
 import javax.swing.ActionMap;
@@ -59,7 +60,7 @@ public ReplaceStringDialog(JabRefFrame parent) {
                 return;
             }
             okPressed = true;
-            fieldStrings = fieldsField.getText().toLowerCase().split(";");
+            fieldStrings = fieldsField.getText().toLowerCase(Locale.ROOT).split(";");
             dispose();
         };
         JButton ok = new JButton(Localization.lang("OK"));

src/main/java/org/jabref/gui/SaveOrderConfigDisplay.java

@@ -3,6 +3,7 @@
 import java.awt.Component;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Objects;
 
 import javax.swing.JCheckBox;
@@ -104,6 +105,6 @@ public SaveOrderConfig getSaveOrderConfig() {
     }
 
     private String getSelectedItemAsLowerCaseTrim(JComboBox<String> sortBox) {
-        return sortBox.getSelectedItem().toString().toLowerCase().trim();
+        return sortBox.getSelectedItem().toString().toLowerCase(Locale.ROOT).trim();
     }
 }

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

@@ -4,6 +4,7 @@
 import java.awt.event.ActionEvent;
 import java.util.Collection;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 import java.util.Set;
 
@@ -223,7 +224,7 @@ public void actionPerformed(ActionEvent e) {
             toSet = null;
         }
 
-        String[] fields = getFieldNames(((String) field.getSelectedItem()).trim().toLowerCase());
+        String[] fields = getFieldNames(((String) field.getSelectedItem()).trim().toLowerCase(Locale.ROOT));
         NamedCompound ce = new NamedCompound(Localization.lang("Set field"));
         if (rename.isSelected()) {
             if (fields.length > 1) {

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

@@ -2,6 +2,7 @@
 
 import java.awt.event.ActionEvent;
 import java.util.Comparator;
+import java.util.Locale;
 import java.util.Map;
 import java.util.TreeMap;
 
@@ -41,6 +42,6 @@ public void actionPerformed(ActionEvent e) {
 
     @Override
     public int compare(String o1, String o2) {
-        return o1.toLowerCase().compareTo(o2.toLowerCase());
+        return o1.toLowerCase(Locale.ROOT).compareTo(o2.toLowerCase(Locale.ROOT));
     }
 }

src/main/java/org/jabref/gui/bibtexkeypattern/BibtexKeyPatternPanel.java

@@ -7,6 +7,7 @@
 import java.awt.GridBagLayout;
 import java.awt.Insets;
 import java.util.HashMap;
+import java.util.Locale;
 import java.util.Map;
 
 import javax.swing.BorderFactory;
@@ -111,7 +112,7 @@ private void buildGUI() {
         }
 
         for (EntryType type : EntryTypes.getAllValues(mode)) {
-            textFields.put(type.getName().toLowerCase(), addEntryType(pan, type, y));
+            textFields.put(type.getName().toLowerCase(Locale.ROOT), addEntryType(pan, type, y));
             y++;
         }
 
@@ -194,7 +195,7 @@ private JTextField addEntryType(Container c, EntryType type, int y) {
         con.anchor = GridBagConstraints.CENTER;
         con.insets = new Insets(0, 5, 0, 5);
         gbl.setConstraints(but, con);
-        but.setActionCommand(type.getName().toLowerCase());
+        but.setActionCommand(type.getName().toLowerCase(Locale.ROOT));
         but.addActionListener(e -> {
             JTextField tField = textFields.get(e.getActionCommand());
             tField.setText("");

src/main/java/org/jabref/gui/customentrytypes/EntryTypeList.java

@@ -3,6 +3,7 @@
 import java.awt.GridBagConstraints;
 import java.awt.event.ActionListener;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 
 import javax.swing.JButton;
@@ -50,7 +51,7 @@ public EntryTypeList(List<String> fields, BibDatabaseMode mode) {
     protected void addField(String str) {
         String s = str.trim();
         if (forceLowerCase) {
-            s = s.toLowerCase();
+            s = s.toLowerCase(Locale.ROOT);
         }
         if ("".equals(s) || listModel.contains(s)) {
             return;

src/main/java/org/jabref/gui/customentrytypes/FieldSetComponent.java

@@ -13,6 +13,7 @@
 import java.util.Enumeration;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Locale;
 import java.util.Set;
 
 import javax.swing.Box;
@@ -235,7 +236,7 @@ public void setFields(List<String> fields) {
     protected void addField(String str) {
         String s = str.trim();
         if (forceLowerCase) {
-            s = s.toLowerCase();
+            s = s.toLowerCase(Locale.ROOT);
         }
         if ("".equals(s) || listModel.contains(s)) {
             return;

src/main/java/org/jabref/gui/desktop/JabRefDesktop.java

@@ -5,6 +5,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 import java.util.regex.Pattern;
 
@@ -136,7 +137,7 @@ public static boolean openExternalFileAnyFormat(final BibDatabaseContext databas
             final Optional<ExternalFileType> type) throws IOException {
         boolean httpLink = false;
 
-        if (REMOTE_LINK_PATTERN.matcher(link.toLowerCase()).matches()) {
+        if (REMOTE_LINK_PATTERN.matcher(link.toLowerCase(Locale.ROOT)).matches()) {
             httpLink = true;
         }
 

src/main/java/org/jabref/gui/desktop/os/Linux.java

@@ -6,6 +6,7 @@
 import java.io.InputStreamReader;
 import java.nio.file.Paths;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 import java.util.StringJoiner;
 
@@ -49,7 +50,7 @@ public void openFileWithApplication(String filePath, String application) throws
 
     @Override
     public void openFolderAndSelectFile(String filePath) throws IOException {
-        String desktopSession = System.getenv("DESKTOP_SESSION").toLowerCase();
+        String desktopSession = System.getenv("DESKTOP_SESSION").toLowerCase(Locale.ROOT);
 
         String cmd;
 

src/main/java/org/jabref/gui/entryeditor/FieldExtraComponents.java

@@ -8,6 +8,7 @@
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
+import java.util.Locale;
 import java.util.Optional;
 import java.util.Set;
 
@@ -337,7 +338,7 @@ public static Optional<JComponent> getYesNoExtraComponent(FieldEditor fieldEdito
         final String[] options = {"", "Yes", "No"};
         JComboBox<String> yesno = new JComboBox<>(options);
         yesno.addActionListener(actionEvent -> {
-            fieldEditor.setText(((String) yesno.getSelectedItem()).toLowerCase());
+            fieldEditor.setText(((String) yesno.getSelectedItem()).toLowerCase(Locale.ROOT));
             entryEditor.updateField(fieldEditor);
         });
         return Optional.of(yesno);

src/main/java/org/jabref/gui/entryeditor/FileAnnotationTab.java

@@ -6,6 +6,7 @@
 import java.util.Arrays;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.StringJoiner;
 
@@ -168,7 +169,7 @@ private void updateFileNameComboBox() {
             indexSelectedByComboBox = fileNameComboBox.getSelectedIndex();
         }
         fileNameComboBox.removeAllItems();
-        new EntryAnnotationImporter(parent.getEntry()).getFilteredFileList().stream().filter(parsedFileField -> parsedFileField.getLink().toLowerCase().endsWith(".pdf"))
+        new EntryAnnotationImporter(parent.getEntry()).getFilteredFileList().stream().filter(parsedFileField -> parsedFileField.getLink().toLowerCase(Locale.ROOT).endsWith(".pdf"))
                 .forEach(((parsedField) -> fileNameComboBox.addItem(parsedField.getLink())));
         fileNameComboBox.setSelectedIndex(indexSelectedByComboBox);
         updateShownAnnotations(annotationsOfFiles.get(fileNameComboBox.getSelectedItem().toString()));

src/main/java/org/jabref/gui/exporter/ExportFileFilter.java

@@ -1,6 +1,7 @@
 package org.jabref.gui.exporter;
 
 import java.io.File;
+import java.util.Locale;
 
 import javax.swing.filechooser.FileFilter;
 
@@ -37,7 +38,7 @@ public boolean accept(File file) {
         if (file.isDirectory()) {
             return true;
         } else {
-            return file.getPath().toLowerCase().endsWith(extension);
+            return file.getPath().toLowerCase(Locale.ROOT).endsWith(extension);
         }
     }
 

src/main/java/org/jabref/gui/externalfiletype/ExternalFileMenuItem.java

@@ -4,6 +4,7 @@
 import java.awt.event.ActionListener;
 import java.io.File;
 import java.io.IOException;
+import java.util.Locale;
 import java.util.Optional;
 
 import javax.swing.Icon;
@@ -73,7 +74,7 @@ public boolean openLink() {
                     String name = file.getName();
                     int pos = name.indexOf('.');
                     String extension = (pos >= 0) && (pos < (name.length() - 1)) ? name.substring(pos + 1)
-                            .trim().toLowerCase() : null;
+                            .trim().toLowerCase(Locale.ROOT) : null;
                     // Now we know the extension, check if it is one we know about:
                     type = ExternalFileTypes.getInstance().getExternalFileTypeByExt(extension);
                     fileType = type;

src/main/java/org/jabref/gui/externalfiletype/ExternalFileTypes.java

@@ -2,6 +2,7 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 import java.util.Set;
 import java.util.TreeSet;
@@ -178,7 +179,7 @@ public Optional<ExternalFileType> getExternalFileTypeForName(String filename) {
         int longestFound = -1;
         ExternalFileType foundType = null;
         for (ExternalFileType type : externalFileTypes) {
-            if (!type.getExtension().isEmpty() && filename.toLowerCase().endsWith(type.getExtension().toLowerCase())
+            if (!type.getExtension().isEmpty() && filename.toLowerCase(Locale.ROOT).endsWith(type.getExtension().toLowerCase(Locale.ROOT))
                     && (type.getExtension().length() > longestFound)) {
                 longestFound = type.getExtension().length();
                 foundType = type;

src/main/java/org/jabref/gui/groups/WarnAssignmentSideEffects.java

@@ -4,6 +4,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 
 import javax.swing.JOptionPane;
 
@@ -30,7 +31,7 @@ public static boolean warnAssignmentSideEffects(List<AbstractGroup> groups, Comp
         for (AbstractGroup group : groups) {
             if (group instanceof KeywordGroup) {
                 KeywordGroup keywordGroup = (KeywordGroup) group;
-                String field = keywordGroup.getSearchField().toLowerCase();
+                String field = keywordGroup.getSearchField().toLowerCase(Locale.ROOT);
                 if (FieldName.KEYWORDS.equals(field) || FieldName.GROUPS.equals(field)) {
                     continue; // this is not undesired
                 }
@@ -62,7 +63,7 @@ public static boolean warnAssignmentSideEffects(List<AbstractGroup> groups, Comp
 
         // if (groups instanceof KeywordGroup) {
         // KeywordGroup kg = (KeywordGroup) groups;
-        // String field = kg.getSearchField().toLowerCase();
+        // String field = kg.getSearchField().toLowerCase(Locale.ROOT);
         // if (field.equals("keywords"))
         // return true; // this is not undesired
         // for (int i = 0; i < GUIGlobals.ALL_FIELDS.length; ++i) {

src/main/java/org/jabref/gui/importer/EntryFromPDFCreator.java

@@ -7,6 +7,7 @@
 import java.util.Calendar;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 
 import org.jabref.Globals;
@@ -50,7 +51,7 @@ private static ExternalFileType getPDFExternalFileType() {
      */
     @Override
     public boolean accept(File f) {
-        return (f != null) && f.getName().toUpperCase().endsWith(".PDF");
+        return (f != null) && f.getName().toUpperCase(Locale.ROOT).endsWith(".PDF");
     }
 
     @Override

src/main/java/org/jabref/gui/importer/fetcher/IEEEXploreFetcher.java

@@ -9,6 +9,7 @@
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Locale;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.regex.Matcher;
@@ -297,7 +298,7 @@ private BibEntry cleanup(BibEntry entry) {
         // clean up month
         entry.getField(FieldName.MONTH).filter(month -> !month.isEmpty()).ifPresent(dirtyMonth -> {
             String month = dirtyMonth.replace(".", "");
-            month = month.toLowerCase();
+            month = month.toLowerCase(Locale.ROOT);
 
             Matcher mm = MONTH_PATTERN.matcher(month);
             StringBuilder date = new StringBuilder(month);

src/main/java/org/jabref/gui/keyboard/EmacsKeyBindings.java

@@ -7,6 +7,7 @@
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.Locale;
 
 import javax.swing.Action;
 import javax.swing.JEditorPane;
@@ -731,7 +732,7 @@ public void actionPerformed(ActionEvent event)
                     jtc.setSelectionStart(start);
                     jtc.setSelectionEnd(end);
                     String word = jtc.getText(start, end - start);
-                    jtc.replaceSelection(word.toLowerCase());
+                    jtc.replaceSelection(word.toLowerCase(Locale.ROOT));
 
                     /* actual capitalize code */
                     int offs = Utilities.getWordStart(jtc, start);
@@ -747,7 +748,7 @@ public void actionPerformed(ActionEvent event)
                     if (Character.isLetter(c.charAt(0))) {
                         jtc.setSelectionStart(offs);
                         jtc.setSelectionEnd(offs + 1);
-                        jtc.replaceSelection(c.toUpperCase());
+                        jtc.replaceSelection(c.toUpperCase(Locale.ROOT));
                     }
                     end = Utilities.getWordEnd(jtc, offs);
                     jtc.setCaretPosition(end);
@@ -782,7 +783,7 @@ public void actionPerformed(ActionEvent event)
                     jtc.setSelectionStart(start);
                     jtc.setSelectionEnd(end);
                     String word = jtc.getText(start, end - start);
-                    jtc.replaceSelection(word.toLowerCase());
+                    jtc.replaceSelection(word.toLowerCase(Locale.ROOT));
                     jtc.setCaretPosition(end);
                 } catch (BadLocationException ble) {
                     jtc.getToolkit().beep();
@@ -815,7 +816,7 @@ public void actionPerformed(ActionEvent event)
                     jtc.setSelectionStart(start);
                     jtc.setSelectionEnd(end);
                     String word = jtc.getText(start, end - start);
-                    jtc.replaceSelection(word.toUpperCase());
+                    jtc.replaceSelection(word.toUpperCase(Locale.ROOT));
                     jtc.setCaretPosition(end);
                 } catch (BadLocationException ble) {
                     jtc.getToolkit().beep();