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

*** 152,161 ****
--- 152,162 ----
  
      /* use serialVersionUID from modified java.util.Date for
       * interoperability with JDK1.1. The Date was modified to write
       * and read only the UTC time.
       */
+     @java.io.Serial
      private static final long serialVersionUID = 7523967970034938905L;
  
      /**
       * Allocates a {@code Date} object and initializes it so that
       * it represents the time at which it was allocated, measured to the
*** 1316,1335 ****
--- 1317,1338 ----
       *
       * @serialData The value returned by {@code getTime()}
       *             is emitted (long).  This represents the offset from
       *             January 1, 1970, 00:00:00 GMT in milliseconds.
       */
+     @java.io.Serial
      private void writeObject(ObjectOutputStream s)
           throws IOException
      {
          s.defaultWriteObject();
          s.writeLong(getTimeImpl());
      }
  
      /**
       * Reconstitute this object from a stream (i.e., deserialize it).
       */
+     @java.io.Serial
      private void readObject(ObjectInputStream s)
           throws IOException, ClassNotFoundException
      {
          s.defaultReadObject();
          fastTime = s.readLong();