--- old/src/java.base/share/classes/java/nio/file/attribute/UserPrincipalNotFoundException.java	2019-08-27 17:28:18.938324386 -0700
+++ new/src/java.base/share/classes/java/nio/file/attribute/UserPrincipalNotFoundException.java	2019-08-27 17:28:18.758324386 -0700
@@ -37,6 +37,7 @@
 public class UserPrincipalNotFoundException
     extends IOException
 {
+    @java.io.Serial
     static final long serialVersionUID = -5369283889045833024L;
 
     private final String name;