diff a/src/java.base/share/classes/java/security/Permissions.java b/src/java.base/share/classes/java/security/Permissions.java
--- a/src/java.base/share/classes/java/security/Permissions.java
+++ b/src/java.base/share/classes/java/security/Permissions.java
@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 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
@@ -574,16 +574,20 @@
     @java.io.Serial
     private static final ObjectStreamField[] serialPersistentFields = {
         new ObjectStreamField("perms", Hashtable.class),
     };
 
-    /**
+    /*
      * @serialData Default fields.
      */
-    /*
+
+    /**
      * Writes the contents of the permsMap field out as a Hashtable for
      * serialization compatibility with earlier releases.
+     *
+     * @param  out the {@code ObjectOutputStream} to which data is written
+     * @throws IOException if an I/O error occurs
      */
     @java.io.Serial
     private void writeObject(ObjectOutputStream out) throws IOException {
         // Don't call out.defaultWriteObject()
 
@@ -596,13 +600,17 @@
         ObjectOutputStream.PutField pfields = out.putFields();
         pfields.put("perms", perms);
         out.writeFields();
     }
 
-    /*
+    /**
      * Reads in a Hashtable of Permission/Permission and saves them in the
      * permsMap field.
+     *
+     * @param  in 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(ObjectInputStream in) throws IOException,
     ClassNotFoundException {
         // Don't call defaultReadObject()
