Support for display names.

src/main/java/org/meeuw/i18n/languages/DisplayNames_en.java

@@ -0,0 +1,15 @@
+package org.meeuw.i18n.languages;
+
+import java.util.stream.Stream;
+
+public class DisplayNames_en extends java.util.ListResourceBundle {
+    @Override
+    protected Object[][] getContents() {
+        return Stream.concat(
+            Stream.of(ISO_639_1_Code.values()),
+            ISO_639_3_Code.stream())
+            .map(i -> new Object[] {i.code(), i.refName()})
+            .toArray(i -> new Object[i][2]);
+
+    }
+}

src/main/java/org/meeuw/i18n/languages/ISO_639_Code.java

@@ -2,6 +2,7 @@
 
 import java.io.Serializable;
 import java.util.Locale;
+import java.util.ResourceBundle;
 
 import jakarta.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
 
@@ -56,4 +57,10 @@ static ISO_639_Code fromCode(String code) {
     }
 
 
+    default String getDisplayName(Locale locale) {
+        ResourceBundle bundle =  ResourceBundle.getBundle("org.meeuw.i18n.languages.DisplayNames", locale);
+        return bundle.getString(code());
+
+    }
+
 }

src/main/java/org/meeuw/i18n/languages/LanguageCode.java

@@ -378,6 +378,8 @@ default NameRecord nameRecord(Locale locale) {
         }
     }
 
+
+
     /**
      * The macro language(s) of which this language is a part.
      * @return a list of macro languages, or an empty list if this language is not known to be a part of a macro language.

src/main/resources/org/meeuw/i18n/languages/DisplayNames_nl.properties

@@ -0,0 +1,7 @@
+dse=Nederlandse Gebarentaal
+vgt=Vlaamse Gebarentaal
+ase=Amerikaanse Gebarentaal
+bfi=Britse Gebarentaal
+csl=Chinese Gebarentaal
+gsg=Duitse Gebarentaal
+tsm=Turkse Gebarentaal

src/test/java/org/meeuw/i18n/languages/test/LanguageCodeTest.java

@@ -5,6 +5,8 @@
 
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
 import org.meeuw.i18n.languages.*;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -210,6 +212,20 @@ public void deprecated() {
         assertThat(LanguageCode.getByPart3("nld")).contains((LanguageCode) ISO_639.get("nl").get());
     }
 
+    @ParameterizedTest
+    @ValueSource(strings = {"dse"})
+    public void signLanguage(String code) {
+        LanguageCode l = LanguageCode.get(code).orElseThrow();
+
+        assertThat(l.refName()).isEqualTo("Dutch Sign Language");
+        assertThat(l.nameRecord().print()).isEqualTo("dse (Dutch Sign Language)");
+        assertThat(new Locale(l.code()).getDisplayName(Locale.US)).isEqualTo("dse");
+
+        assertThat(l.getDisplayName(Locale.US)).isEqualTo("Dutch Sign Language");
+
+        assertThat(l.getDisplayName(new Locale("nl"))).isEqualTo("Nederlandse Gebarentaal");
+    }
+
 
     // TODO
     @Disabled