--- old/src/java.base/share/classes/java/util/regex/Pattern.java	2019-08-27 17:29:18.370324386 -0700
+++ new/src/java.base/share/classes/java/util/regex/Pattern.java	2019-08-27 17:29:18.190324386 -0700
@@ -935,6 +935,7 @@
      */
 
     /** use serialVersionUID from Merlin b59 for interoperability */
+    @java.io.Serial
     private static final long serialVersionUID = 5073258162644648461L;
 
     /**
@@ -1376,6 +1377,7 @@
      * Recompile the Pattern instance from a stream.  The original pattern
      * string is read in and the object tree is recompiled from it.
      */
+    @java.io.Serial
     private void readObject(java.io.ObjectInputStream s)
         throws java.io.IOException, ClassNotFoundException {