Some systems like to provide their own standard, so offer to work aru…

…nd that.

src/main/java/org/meeuw/i18n/languages/ISO_639.java

@@ -1,18 +1,22 @@
 package org.meeuw.i18n.languages;
 
-import com.fasterxml.jackson.annotation.JsonCreator;
-import jakarta.validation.constraints.Size;
 import java.util.*;
 import java.util.stream.Stream;
+
+import jakarta.validation.constraints.Size;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+
 import static org.meeuw.i18n.languages.ISO_639_3_Code.KNOWN;
 
 /**
  * A utility class for working with ISO 639 language codes.
- * 
+ *
  * @since 3.1
  */
+
 public class ISO_639 {
-    
+
     private ISO_639() {
     }
     /**
@@ -21,7 +25,7 @@ private ISO_639() {
      * @param code A 2 letter language code
      * @return An optional containing the {@link ISO_639_3_Code} if found.
      */
-    
+
     public static Optional<LanguageCode> getByPart1(String code) {
         return  ISO_639_3_Code
             .getByPart1(code)
@@ -72,7 +76,7 @@ public static Optional<LanguageCode> getByPart2T(String code) {
      * @since 2.2
      */
     public static Optional<LanguageCode> getByPart3(@Size(min = 3, max = 3) String code, boolean matchRetired) {
-        
+
         return ISO_639_3_Code.getByPart3(code, matchRetired)
             .map(LanguageCode::updateToEnum)
             ;
@@ -86,18 +90,18 @@ public static Optional<LanguageCode> getByPart3(@Size(min = 3, max = 3) String c
     }
 
     /**
-     * Retrieves a language family code by its 3 letter code.
-     * 
-     * @see LanguageFamilyCode#get(String) 
+     * Retrieves a language family code by its 3-letter code.
+     *
+     * @see LanguageFamilyCode#get(String)
      */
     public static Optional<LanguageFamilyCode> getByPart5(@Size(min = 3, max = 3) String code) {
-        
+
         return LanguageFamilyCode.get(code);
     }
 
     /**
      * A stream with all known {@link ISO_639_Code language (or language family) codes} .
-     * 
+     *
      *
      * @return a stream of all known language codes.
      */
@@ -116,18 +120,29 @@ public static Stream<ISO_639_Code> stream() {
         );
     }
 
+
+    private static final Map<String, ISO_639_Code> FALLBACKS = new HashMap<>();
+
+    public static void registerFallback(String code, ISO_639_Code exemption) {
+        FALLBACKS.put(code, exemption);
+    }
+
+    public static Map<String, ISO_639_Code> getFallBacks() {
+        return FALLBACKS;
+    }
+
     /**
      * Obtains a language or language family by (one of their) code(s).
-     * 
-     * @see #get For a version that throws an exception if not found. 
+     *
+     * @see #get For a version that throws an exception if not found.
      */
     public static Optional<ISO_639_Code> get(String code) {
         ISO_639_Code lc = LanguageCode.get(code).orElse(null);
         if (lc == null) {
             try {
                 return Optional.of(LanguageFamilyCode.valueOf(code));
             } catch (IllegalArgumentException iae) {
-                return Optional.empty();
+                return Optional.ofNullable(FALLBACKS.get(code));
             }
         } else {
             return Optional.of(lc);

src/main/java/org/meeuw/i18n/languages/ISO_639_3_Code.java

@@ -1,31 +1,33 @@
 package org.meeuw.i18n.languages;
 
-import com.fasterxml.jackson.annotation.JsonValue;
-import jakarta.validation.constraints.NotNull;
-import jakarta.validation.constraints.Size;
 import java.io.*;
 import java.nio.charset.StandardCharsets;
 import java.util.*;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import java.util.stream.Stream;
 
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Size;
+
+import com.fasterxml.jackson.annotation.JsonValue;
+
 /**
  * Implementation of {@link LanguageCode} that {@link ISO_639#stream() produces} all ISO-639-3 codes.
  * <p>
- * Normally it makes sense to just use {@link LanguageCode}. 
- 
+ * Normally it makes sense to just use {@link LanguageCode}.
+
  */
 public class ISO_639_3_Code implements LanguageCode {
 
     final static Logger LOGGER = Logger.getLogger(LanguageCode.class.getName());
 
 
     static final Map<String, ISO_639_3_Code> KNOWN;
-    
-    
+
+
     static final Map<LanguageCode, List<LanguageCode>> INDIVIDUAL_LANGUAGES;
-    
+
     static final Map<LanguageCode, List<LanguageCode>> MACRO;
 
 
@@ -74,7 +76,7 @@ public class ISO_639_3_Code implements LanguageCode {
             throw new ExceptionInInitializerError(e);
         }
         KNOWN = Collections.unmodifiableMap(temp);
-        
+
         Map<LanguageCode, List<LanguageCode>> tempIndividual = new HashMap<>();
         Map<LanguageCode, List<LanguageCode>> tempMacro = new HashMap<>();
         try (InputStream inputStream = ISO_639_3_Code.class.getResourceAsStream(DIR + "iso-639-3-macrolanguages.tab");
@@ -100,34 +102,35 @@ public class ISO_639_3_Code implements LanguageCode {
         }
         tempIndividual.replaceAll((k, v) -> Collections.unmodifiableList(v));
         tempMacro.replaceAll((k, v) -> Collections.unmodifiableList(v));
-        
+
         INDIVIDUAL_LANGUAGES = Collections.unmodifiableMap(tempIndividual);
         MACRO = Collections.unmodifiableMap(tempMacro);
     }
-    
+
     /**
      * A stream with all known {@link ISO_639_Code language codes}.
      * If the langauge has a 2 letter part 1 code, it will <em>not</em> be implicitly upgraded
      * to an {@link ISO_639_1_Code
      *
      * @see {@link LanguageCode#stream()} For a version that <em>does</em> upgrade
-     * @return a stream of all known language codes. 
-     * 
+     * @return a stream of all known language codes.
+     *
      */
      public static Stream<ISO_639_3_Code> stream() {
         return KNOWN.values()
             .stream()
             .sorted(Comparator.comparing(ISO_639_3_Code::code));
      }
-    
+
     private static final Map<String, String> RETIRED = new HashMap<>();
     static {
         RETIRED.put("jw", "jv"); // 'Javanese is rendered as "jw" in table 1, while it is correctly given as "jv" in the other tables
         RETIRED.put("iw", "he"); // The identifier for Hebrew was changed from "iw" to "he".
         RETIRED.put("in", "id"); // The identifier for Indonesian was changed from "in" to "id".
         RETIRED.put("ji", "yi"); // The identifier for Yiddish was changed from "ji" to "yi".
     }
-
+
+
     static Optional<ISO_639_3_Code> getByPart1(String code) {
         if (code == null) {
             return Optional.empty();
@@ -139,8 +142,8 @@ static Optional<ISO_639_3_Code> getByPart1(String code) {
             .filter(i -> finalCode.equals(i.part1()))
             .findFirst();
     }
-    
-    
+
+
     /**
      * Retrieves a {@link ISO_639_3_Code} by its three-letter identifier {@link ISO_639#getByPart3(String, boolean)} ()}
      * <p>
@@ -210,7 +213,7 @@ private ISO_639_3_Code(
         this.names  = Collections.unmodifiableList(names);
     }
 
-  
+
     /**
      * The {@link #part1() ISO-639-1-code} if available, otherwise the {@link #part3() ISO-639-3 code}.
      *
@@ -229,7 +232,7 @@ public String toString() {
     }
 
 
-    
+
     public String part3() {
         return part3;
     }
@@ -283,7 +286,7 @@ public String comment() {
     public List<NameRecord> nameRecords() {
         return names;
     }
-    
+
     @Size
     public NameRecord nameRecord(Locale locale) {
         if (locale.getLanguage().equals("en")) {
@@ -306,5 +309,5 @@ public List<LanguageCode> individualLanguages() {
     private Object readResolve() {
         return LanguageCode.get(part3()).orElse(this);
     }
-    
+
 }