Add UI language selector (ui.language), fixes #444

distribution/doc/release-notes/3.2.0.md

@@ -6,3 +6,5 @@ A release about getting out of your way. The improvements below smooth over the
 - **Preferences dialog gains a _General_ tab** gathering the signing-engine selection and the new `debug` toggle; both apply immediately.
 - **Visible signature images keep their aspect ratio with the DSS engine** — background and graphic images were previously stretched to fill the signature box and came out distorted. A `--bg-scale` of zero still stretches to fill; any other value fits the image and centers it, matching the OpenPDF engine. See issue 460.
 - **Clear list in the Recent files menu** — the File menu's recent-files trail can now be emptied on its own, which previously required a factory reset that discarded every other setting as well. The item appears only when there is something to clear. See issue 453.
+- **Pick the interface language** — a new _Language_ selector on the _General_ tab of Preferences lets you choose the UI language explicitly instead of always following the operating-system locale; _System default_ stays the default. It is stored as `ui.language` in `advanced.properties` and works on the command line too (`-o ui.language=de`, e.g. to read `--help` in German). The setting is read at startup, so restart to apply it, and it affects interface text only — number/date formatting and the signed output are unchanged. See issue 444.
+- **Norwegian translation is now loaded** — the bundled Norwegian Bokmål translation shipped under a file name (`messages_nb-NO.properties`) that Java's resource loader never matched, so it silently rendered English. Renaming it to `messages_nb.properties` makes it apply for both `nb` and `nb-NO` locales.

engines/api/src/main/java/net/sf/jsignpdf/utils/AppConfig.java

@@ -43,6 +43,14 @@ public static boolean relaxSslSecurity() {
         return cfg().getAsBool("relax.ssl.security", false);
     }
 
+    /**
+     * BCP-47 language tag of the user interface ({@code ui.language} in {@code advanced.properties}), or {@code null}
+     * when unset. Empty / unset means "follow the OS locale". Read once at startup by {@link UiLocale}.
+     */
+    public static String uiLanguage() {
+        return cfg().getProperty(UiLocale.KEY);
+    }
+
     /**
      * Whether verbose signing diagnostics are enabled ({@code debug} in {@code advanced.properties}). When on,
      * the signing pipeline logs the certificate chain, the loaded trust anchors, and every TSA / AIA / CRL /

engines/api/src/main/java/net/sf/jsignpdf/utils/ResourceProvider.java

@@ -24,7 +24,7 @@
  */
 public class ResourceProvider {
 
-    private ResourceBundle bundle;
+    private volatile ResourceBundle bundle;
 
     /**
      * Constructor which takes a not-<code>null</code> {@link ResourceBundle} as an argument.
@@ -38,6 +38,20 @@ public ResourceProvider(ResourceBundle bundle) {
         this.bundle = bundle;
     }
 
+    /**
+     * Swaps the active {@link ResourceBundle}. Called once at startup by {@link UiLocale#init(String[])}, which owns
+     * the bundle base name and the fallback policy, so every static-import call site keeps reading through this same
+     * shared instance.
+     *
+     * @param newBundle the bundle to read from, not-<code>null</code>
+     */
+    public void reload(final ResourceBundle newBundle) {
+        if (newBundle == null) {
+            throw new IllegalArgumentException("ResourceBundle must be not-null.");
+        }
+        this.bundle = newBundle;
+    }
+
     /**
      * Sets translations and mnemonics for labels and different kind of buttons
      *

engines/api/src/main/java/net/sf/jsignpdf/utils/SupportedLanguages.java

@@ -0,0 +1,57 @@
+package net.sf.jsignpdf.utils;
+
+import java.util.List;
+import java.util.Locale;
+
+/**
+ * The bundled UI translations, as BCP-47 language tags. Kept as a static list (not a classpath scan) so it works
+ * unchanged from a jar, a jlink image or a jpackage bundle. {@code SupportedLanguagesTest} guards it against the
+ * actual {@code messages*.properties} files.
+ */
+public final class SupportedLanguages {
+
+    /** English (the base bundle) first; the rest sorted by tag. Region kept only where it disambiguates (zh). */
+    private static final List<String> TAGS = List.of(
+            "en", "cs", "de", "el", "es", "fr", "hr", "hu", "hy", "it",
+            "ja", "nb", "pl", "pt", "ru", "sk", "ta", "zh-CN", "zh-TW");
+
+    private SupportedLanguages() {
+    }
+
+    /** BCP-47 tags of the bundled translations, English first. */
+    public static List<String> tags() {
+        return TAGS;
+    }
+
+    /**
+     * Whether a translation exists for the given locale. Matches the exact language+region tag (so {@code zh-CN}
+     * resolves) and, failing that, the language alone (so {@code nb-NO} or {@code pt-BR} resolve to {@code nb} / {@code pt}).
+     */
+    public static boolean isSupported(Locale locale) {
+        if (locale == null) {
+            return false;
+        }
+        return TAGS.contains(locale.toLanguageTag()) || TAGS.contains(locale.getLanguage());
+    }
+
+    /**
+     * Label for the selector: native name plus English name, e.g. {@code "Deutsch (German)"}. The English part keeps
+     * the list readable to someone who cannot read the current UI language — the scenario behind issue #444. Names
+     * carrying a region already bracket it, so those get an en-dash separator ({@code "中文 (中国) – Chinese (China)"})
+     * rather than a second, nested pair of parentheses.
+     */
+    public static String displayName(Locale locale) {
+        String self = locale.getDisplayName(locale);
+        String english = locale.getDisplayName(Locale.ENGLISH);
+        if (self.isEmpty()) {
+            return english;
+        }
+        if (self.equalsIgnoreCase(english)) {
+            return self;
+        }
+        if (self.indexOf('(') >= 0 || english.indexOf('(') >= 0) {
+            return self + " – " + english;
+        }
+        return self + " (" + english + ")";
+    }
+}

engines/api/src/main/java/net/sf/jsignpdf/utils/UiLocale.java

@@ -0,0 +1,175 @@
+package net.sf.jsignpdf.utils;
+
+import java.util.Locale;
+import java.util.ResourceBundle;
+import java.util.logging.Level;
+
+import net.sf.jsignpdf.Constants;
+
+/**
+ * Resolves the configured UI locale ({@code ui.language} in the advanced configuration) and installs it before any
+ * translated string is read. {@link #init(String[])} must run first thing in {@code main()}, because
+ * {@link Constants#RES} and the commons-cli option descriptions capture strings during class initialization.
+ *
+ * <p>The choice is installed as the base default plus {@link Locale.Category#DISPLAY}, while
+ * {@link Locale.Category#FORMAT} is pinned to the OS locale: UI text follows the choice while number/date formatting
+ * keeps following the OS locale, so a UI-language preference can never change signed output. The base default matters
+ * because {@code ResourceBundle.getBundle(baseName)} without an explicit locale resolves against
+ * {@link Locale#getDefault()} and ignores the DISPLAY category — that is how JavaFX loads its own control strings
+ * (the OK / Cancel labels of {@code ButtonType}, text-field context menus), which would otherwise stay in the OS
+ * language and produce a half-translated UI.
+ */
+public final class UiLocale {
+
+    /** Advanced-config key holding the BCP-47 UI language tag. */
+    public static final String KEY = "ui.language";
+
+    // getBundle(base, locale) falls back to the default-locale bundle before the base bundle. A no-fallback control
+    // keeps the chain messages_<chosen> -> messages (English) only, so a missing key never leaks the OS-locale text.
+    // The Control overloads are unusable from a *named* module; JSignPdf ships on the classpath (jpackage images
+    // included), so this is fine.
+    private static final ResourceBundle.Control NO_FALLBACK =
+            ResourceBundle.Control.getNoFallbackControl(ResourceBundle.Control.FORMAT_PROPERTIES);
+
+    private static final Locale SYSTEM_DEFAULT = Locale.getDefault(Locale.Category.DISPLAY);
+
+    private static volatile Locale current = SYSTEM_DEFAULT;
+
+    private UiLocale() {
+    }
+
+    /**
+     * Resolves and installs the UI locale. Reads {@code -o ui.language=<tag>} from the raw argv first (so
+     * {@code --help} is consistent), then the advanced configuration. An empty, missing, unparseable or unsupported
+     * value leaves the system default in place.
+     */
+    public static void init(String[] args) {
+        String tag = scanArgs(args);
+        if (tag == null) {
+            tag = AppConfig.uiLanguage();
+        }
+        Locale locale = resolve(tag);
+        if (locale == null) {
+            current = SYSTEM_DEFAULT;
+            return;
+        }
+        current = locale;
+        // setDefault(Locale) sets the base default and both categories; pin FORMAT back to the OS locale afterwards
+        // so number/date formatting - and therefore the signed output - is untouched by a UI-language choice.
+        final Locale osFormat = Locale.getDefault(Locale.Category.FORMAT);
+        Locale.setDefault(locale);
+        Locale.setDefault(Locale.Category.FORMAT, osFormat);
+        ResourceBundle.clearCache();
+        Constants.RES.reload(bundle());
+    }
+
+    /** The resolved UI locale (the system default when unset). */
+    public static Locale current() {
+        return current;
+    }
+
+    /** The OS display locale, unaffected by an installed {@code ui.language} choice. */
+    public static Locale systemDefault() {
+        return SYSTEM_DEFAULT;
+    }
+
+    /** A {@link ResourceBundle} for {@link #current()} with English-only fallback (no OS-locale fallback). */
+    public static ResourceBundle bundle() {
+        return bundle(current);
+    }
+
+    /** A {@link ResourceBundle} for the given locale with English-only fallback (no OS-locale fallback). */
+    public static ResourceBundle bundle(Locale locale) {
+        return ResourceBundle.getBundle(Constants.RESOURCE_BUNDLE_BASE, locale, NO_FALLBACK);
+    }
+
+    /**
+     * Maps a configured tag to the matching entry of {@link SupportedLanguages#tags()}, or {@code ""} when it resolves
+     * to no bundled translation. Lets the Preferences selector show a hand-edited {@code zh_CN} or {@code de-AT} as the
+     * {@code zh-CN} / {@code de} item it actually loads, instead of an unselected entry.
+     */
+    public static String canonicalTag(String tag) {
+        Locale locale = resolve(tag);
+        if (locale == null) {
+            return "";
+        }
+        String exact = locale.toLanguageTag();
+        return SupportedLanguages.tags().contains(exact) ? exact : locale.getLanguage();
+    }
+
+    /**
+     * Resolves a configured tag to a supported {@link Locale}, or {@code null} to keep the system default. Underscores
+     * are normalised to hyphens (so a hand-edited {@code zh_CN} works), the legacy Norwegian macrolanguage code
+     * {@code no} is mapped to {@code nb} (Java does not do this itself), and a region-less {@code zh} is expanded to
+     * {@code zh-CN} — the CLDR likely-subtags expansion, and the only way a bare {@code zh} can pick one of the two
+     * Chinese bundles rather than falling back to English.
+     */
+    static Locale resolve(String tag) {
+        if (tag == null) {
+            return null;
+        }
+        String normalized = tag.trim().replace('_', '-');
+        if (normalized.isEmpty()) {
+            return null;
+        }
+        if (normalized.equalsIgnoreCase("no")) {
+            normalized = "nb";
+        } else if (normalized.regionMatches(true, 0, "no-", 0, 3)) {
+            normalized = "nb" + normalized.substring(2);
+        } else if (normalized.equalsIgnoreCase("zh")) {
+            normalized = "zh-CN";
+        }
+        Locale locale = Locale.forLanguageTag(normalized);
+        if (locale.getLanguage().isEmpty()) {
+            Constants.LOGGER.log(Level.INFO, "Ignoring unparseable ui.language=" + tag);
+            return null;
+        }
+        if (!SupportedLanguages.isSupported(locale)) {
+            Constants.LOGGER.log(Level.INFO, "Ignoring unsupported ui.language=" + tag);
+            return null;
+        }
+        return locale;
+    }
+
+    /**
+     * Pre-scans raw argv for {@code -o ui.language=<tag>} / {@code --option ui.language=<tag>} (also the attached
+     * {@code --option=...} form). A deliberate, tiny duplicate of the commons-cli parse in {@code SignerOptionsFromCmdLine},
+     * whose class init already needs the final locale. Returns the last matching tag, or {@code null}.
+     */
+    private static String scanArgs(String[] args) {
+        if (args == null) {
+            return null;
+        }
+        String result = null;
+        for (int i = 0; i < args.length; i++) {
+            String arg = args[i];
+            if (arg == null) {
+                continue;
+            }
+            String value = null;
+            if (("-" + Constants.ARG_OPTION).equals(arg) || ("--" + Constants.ARG_OPTION_LONG).equals(arg)) {
+                if (i + 1 < args.length) {
+                    value = args[i + 1];
+                }
+            } else if (arg.startsWith("--" + Constants.ARG_OPTION_LONG + "=")) {
+                value = arg.substring(("--" + Constants.ARG_OPTION_LONG + "=").length());
+            } else if (arg.startsWith("-" + Constants.ARG_OPTION)) {
+                value = arg.substring(("-" + Constants.ARG_OPTION).length());
+            }
+            String tag = tagOf(value);
+            if (tag != null) {
+                result = tag;
+            }
+        }
+        return result;
+    }
+
+    /** Extracts the tag from a {@code ui.language=<tag>} token, or {@code null} if it is not that key. */
+    private static String tagOf(String value) {
+        if (value == null) {
+            return null;
+        }
+        String prefix = KEY + "=";
+        return value.startsWith(prefix) ? value.substring(prefix.length()) : null;
+    }
+}

engines/api/src/main/resources/net/sf/jsignpdf/conf/advanced.default.properties

@@ -17,6 +17,12 @@ engine=openpdf
 # regardless of this setting.
 debug=false
 
+# BCP-47 language tag of the user interface (e.g. de, fr, pt, zh-CN). Empty (the
+# default) follows the operating-system locale. Read once at startup; restart
+# JSignPdf to apply a change. The GUI Preferences dialog writes this key; on the
+# CLI use -o ui.language=<tag>.
+ui.language=
+
 # Engine-specific configuration. Each engine module reads its own keys under the
 # engine.<id>.* prefix (via EngineConfig). No keys are defined for the bundled
 # OpenPDF engine

engines/api/src/main/resources/net/sf/jsignpdf/translations/messages.properties

@@ -508,6 +508,9 @@ jfx.gui.preferences.button.resetSection=Reset section to defaults
 jfx.gui.preferences.restartHint=Takes effect after restart
 jfx.gui.preferences.restartHint.tooltip=This setting is read once at startup. Restart JSignPdf for the change to take effect.
 jfx.gui.preferences.section.general=General
+jfx.gui.preferences.general.language=Language
+jfx.gui.preferences.general.language.help=Language of the JSignPdf user interface. "System default" follows your operating-system settings.
+jfx.gui.preferences.general.language.system=System default ({0})
 jfx.gui.preferences.engine.help=Signing engine used to sign documents. OpenPDF produces standard PDF signatures; DSS produces PAdES baseline signatures (B/T/LT/LTA). The selection applies immediately and is the default for both the GUI and the CLI.
 jfx.gui.preferences.general.debug=Debug output
 jfx.gui.preferences.general.debug.help=Log verbose diagnostics during signing: the signing certificate chain, the loaded trust anchors, and every timestamp / AIA / CRL / OCSP network call. Enable this to investigate a signing failure. Applies immediately to both the GUI and the CLI.

engines/api/src/main/resources/net/sf/jsignpdf/translations/messages_cs.properties

@@ -505,6 +505,9 @@ jfx.gui.preferences.button.resetSection=Obnovit sekci na výchozí
 jfx.gui.preferences.restartHint=Projeví se po restartu
 jfx.gui.preferences.restartHint.tooltip=Toto nastavení se načítá pouze při spuštění. Restartujte JSignPdf, aby se změna projevila.
 jfx.gui.preferences.section.general=Obecné
+jfx.gui.preferences.general.language=Jazyk
+jfx.gui.preferences.general.language.help=Jazyk uživatelského rozhraní JSignPdf. Volba „Výchozí jazyk systému“ se řídí nastavením operačního systému.
+jfx.gui.preferences.general.language.system=Výchozí jazyk systému ({0})
 jfx.gui.preferences.engine.help=Podpisový engine použitý k podepisování dokumentů. OpenPDF vytváří standardní PDF podpisy; DSS vytváří podpisy PAdES (B/T/LT/LTA). Výběr se projeví okamžitě a je výchozí pro GUI i CLI.
 jfx.gui.preferences.general.debug=Ladicí výstup
 jfx.gui.preferences.general.debug.help=Zaznamenávat podrobnou diagnostiku během podpisu: řetězec podpisového certifikátu, načtené kotvy důvěry a každé síťové volání časového razítka / AIA / CRL / OCSP. Zapněte pro řešení selhání podpisu. Projeví se okamžitě pro GUI i CLI.

engines/api/src/main/resources/net/sf/jsignpdf/translations/messages_de.properties

@@ -505,6 +505,9 @@ jfx.gui.preferences.button.resetSection=Abschnitt auf Standardwerte zurücksetze
 jfx.gui.preferences.restartHint=Wird nach Neustart wirksam
 jfx.gui.preferences.restartHint.tooltip=Diese Einstellung wird einmal beim Start gelesen. Starten Sie JSignPdf neu, damit die Änderung wirksam wird.
 jfx.gui.preferences.section.general=Allgemein
+jfx.gui.preferences.general.language=Sprache
+jfx.gui.preferences.general.language.help=Sprache der JSignPdf-Benutzeroberfläche. „Systemvorgabe“ folgt den Einstellungen des Betriebssystems.
+jfx.gui.preferences.general.language.system=Systemvorgabe ({0})
 jfx.gui.preferences.engine.help=Signatur-Engine, die zum Signieren von Dokumenten verwendet wird. OpenPDF erzeugt Standard-PDF-Signaturen; DSS erzeugt PAdES-Baseline-Signaturen (B/T/LT/LTA). Die Auswahl wird sofort wirksam und ist die Vorgabe für die Oberfläche und die Kommandozeile.
 jfx.gui.preferences.general.debug=Debug-Ausgabe
 jfx.gui.preferences.general.debug.help=Ausführliche Diagnose während des Signierens protokollieren: die Zertifikatskette des Unterzeichners, die geladenen Vertrauensanker und jeden Netzwerkaufruf für Zeitstempel / AIA / CRL / OCSP. Aktivieren Sie dies, um einen Signaturfehler zu untersuchen. Wird sofort für die Oberfläche und die Kommandozeile wirksam.

engines/api/src/main/resources/net/sf/jsignpdf/translations/messages_el.properties

@@ -504,6 +504,9 @@ jfx.gui.preferences.button.resetSection=Επαναφορά ενότητας στ
 jfx.gui.preferences.restartHint=Ισχύει μετά την επανεκκίνηση
 jfx.gui.preferences.restartHint.tooltip=Αυτή η ρύθμιση διαβάζεται μία φορά κατά την εκκίνηση. Επανεκκινήστε το JSignPdf για να εφαρμοστεί η αλλαγή.
 jfx.gui.preferences.section.general=Γενικά
+jfx.gui.preferences.general.language=Γλώσσα
+jfx.gui.preferences.general.language.help=Γλώσσα του περιβάλλοντος χρήστη του JSignPdf. Η επιλογή «Προεπιλογή συστήματος» ακολουθεί τις ρυθμίσεις του λειτουργικού συστήματος.
+jfx.gui.preferences.general.language.system=Προεπιλογή συστήματος ({0})
 jfx.gui.preferences.engine.help=Η μηχανή υπογραφής που χρησιμοποιείται για την υπογραφή εγγράφων. Το OpenPDF παράγει τυπικές υπογραφές PDF· το DSS παράγει βασικές υπογραφές PAdES (B/T/LT/LTA). Η επιλογή εφαρμόζεται άμεσα και αποτελεί την προεπιλογή τόσο για το γραφικό περιβάλλον όσο και για τη γραμμή εντολών.
 jfx.gui.preferences.general.debug=Έξοδος αποσφαλμάτωσης
 jfx.gui.preferences.general.debug.help=Καταγραφή αναλυτικών διαγνωστικών κατά την υπογραφή: την αλυσίδα πιστοποιητικών υπογραφής, τις φορτωμένες άγκυρες εμπιστοσύνης και κάθε δικτυακή κλήση χρονοσήμανσης / AIA / CRL / OCSP. Ενεργοποιήστε το για τη διερεύνηση μιας αποτυχίας υπογραφής. Εφαρμόζεται άμεσα τόσο στο γραφικό περιβάλλον όσο και στη γραμμή εντολών.