diff a/src/java.base/share/classes/javax/security/auth/PrivateCredentialPermission.java b/src/java.base/share/classes/javax/security/auth/PrivateCredentialPermission.java
--- a/src/java.base/share/classes/javax/security/auth/PrivateCredentialPermission.java
+++ b/src/java.base/share/classes/javax/security/auth/PrivateCredentialPermission.java
@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
@@ -24,10 +24,11 @@
  */
 
 package javax.security.auth;
 
 import java.util.*;
+import java.io.IOException;
 import java.text.MessageFormat;
 import java.security.Permission;
 import java.security.PermissionCollection;
 import java.security.Principal;
 import sun.security.util.ResourcesMgr;
@@ -473,14 +474,18 @@
         return true;
     }
 
     /**
      * Reads this object from a stream (i.e., deserializes it)
+     *
+     * @param  s the {@code ObjectInputStream} from which data is read
+     * @throws IOException if an I/O error occurs
+     * @throws ClassNotFoundException if a serialized class cannot be loaded
      */
     @java.io.Serial
     private void readObject(java.io.ObjectInputStream s) throws
-                                        java.io.IOException,
+                                        IOException,
                                         ClassNotFoundException {
 
         s.defaultReadObject();
 
         // perform new initialization from the permission name
