src/java.base/share/classes/java/util/Locale.java

*** 631,640 ****
--- 631,641 ----
       */
      public static final char UNICODE_LOCALE_EXTENSION = 'u';
  
      /** serialization ID
       */
+     @java.io.Serial
      static final long serialVersionUID = 9149081749638150636L;
  
      /**
       * Enum for specifying the type defined in ISO 3166. This enum is used to
       * retrieve the two-letter ISO3166-1 alpha-2, three-letter ISO3166-1
*** 2299,2308 ****
--- 2300,2310 ----
       *      BCP47 private use subtags, all in lower case letters
       *      separated by HYPHEN-MINUS characters.
       *      (See <a href="java.base/java/util/Locale.html#getExtensionKeys()">getExtensionKeys()</a>,
       *      <a href="java.base/java/util/Locale.html#getExtension(char)">getExtension(char)</a>)
       */
+     @java.io.Serial
      private static final ObjectStreamField[] serialPersistentFields = {
          new ObjectStreamField("language", String.class),
          new ObjectStreamField("country", String.class),
          new ObjectStreamField("variant", String.class),
          new ObjectStreamField("hashcode", int.class),
*** 2314,2323 ****
--- 2316,2326 ----
       * Serializes this <code>Locale</code> to the specified <code>ObjectOutputStream</code>.
       * @param out the <code>ObjectOutputStream</code> to write
       * @throws IOException
       * @since 1.7
       */
+     @java.io.Serial
      private void writeObject(ObjectOutputStream out) throws IOException {
          ObjectOutputStream.PutField fields = out.putFields();
          fields.put("language", baseLocale.getLanguage());
          fields.put("script", baseLocale.getScript());
          fields.put("country", baseLocale.getRegion());
*** 2333,2342 ****
--- 2336,2346 ----
       * @throws IOException
       * @throws ClassNotFoundException
       * @throws IllformedLocaleException
       * @since 1.7
       */
+     @java.io.Serial
      private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
          ObjectInputStream.GetField fields = in.readFields();
          String language = (String)fields.get("language", "");
          String script = (String)fields.get("script", "");
          String country = (String)fields.get("country", "");
*** 2369,2378 ****
--- 2373,2383 ----
       *
       * @return an instance of <code>Locale</code> equivalent to
       * the deserialized <code>Locale</code>.
       * @throws java.io.ObjectStreamException
       */
+     @java.io.Serial
      private Object readResolve() throws java.io.ObjectStreamException {
          return getInstance(baseLocale.getLanguage(), baseLocale.getScript(),
                  baseLocale.getRegion(), baseLocale.getVariant(), localeExtensions);
      }