--- old/src/java.base/share/classes/java/util/EnumMap.java	2019-08-27 17:28:54.378324386 -0700
+++ new/src/java.base/share/classes/java/util/EnumMap.java	2019-08-27 17:28:54.194324386 -0700
@@ -754,6 +754,7 @@
                                         .getEnumConstantsShared(keyType);
     }
 
+    @java.io.Serial
     private static final long serialVersionUID = 458661240069192865L;
 
     /**
@@ -765,6 +766,7 @@
      *             and value (Object) for each key-value mapping represented
      *             by the enum map.
      */
+    @java.io.Serial
     private void writeObject(java.io.ObjectOutputStream s)
         throws java.io.IOException
     {
@@ -790,6 +792,7 @@
      * deserialize it).
      */
     @SuppressWarnings("unchecked")
+    @java.io.Serial
     private void readObject(java.io.ObjectInputStream s)
         throws java.io.IOException, ClassNotFoundException
     {