--- old/src/java.base/share/classes/java/time/OffsetTime.java	2019-08-27 17:28:30.866324386 -0700
+++ new/src/java.base/share/classes/java/time/OffsetTime.java	2019-08-27 17:28:30.678324386 -0700
@@ -138,6 +138,7 @@
     /**
      * Serialization version.
      */
+    @java.io.Serial
     private static final long serialVersionUID = 7264499704384272492L;
 
     /**
@@ -1410,6 +1411,7 @@
      *
      * @return the instance of {@code Ser}, not null
      */
+    @java.io.Serial
     private Object writeReplace() {
         return new Ser(Ser.OFFSET_TIME_TYPE, this);
     }
@@ -1420,6 +1422,7 @@
      * @param s the stream to read
      * @throws InvalidObjectException always
      */
+    @java.io.Serial
     private void readObject(ObjectInputStream s) throws InvalidObjectException {
         throw new InvalidObjectException("Deserialization via serialization delegate");
     }