diff a/test/jdk/java/util/Collections/T6433170.java b/test/jdk/java/util/Collections/T6433170.java
--- a/test/jdk/java/util/Collections/T6433170.java
+++ b/test/jdk/java/util/Collections/T6433170.java
@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2026, 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.
@@ -23,12 +23,14 @@
 
 /*
  * @test
  * @bug 6433170
  * @summary CheckedCollection.addAll should be all-or-nothing
+ * @library /test/lib
  */
 
+import jdk.test.lib.valueclass.VClass;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
@@ -38,10 +40,11 @@
 import static java.util.Collections.checkedList;
 import static java.util.Collections.checkedSet;
 
 @SuppressWarnings("unchecked")
 public class T6433170 {
+
     private void checkEmpty(Collection x) {
         check(x.isEmpty());
         check(x.size() == 0);
         check(x.toArray().length == 0);
     }
@@ -54,10 +57,16 @@
                  checkedSet(new HashSet(), String.class),
                  Object.class));
         test(checkedCollection(
                  checkedCollection(new Vector(), String.class),
                  Object.class));
+
+        Collection<VClass> vc = checkedCollection(new ArrayList<>(), VClass.class);
+        List mixed = Arrays.asList(new VClass(1, new int[] { 1 }), new VClass(2, new int[] { 2 }), "not a Tuple");
+        THROWS(ClassCastException.class,
+               new F(){void f(){ vc.addAll(mixed); }});
+        checkEmpty(vc);
     }
 
     void test(final Collection checked) {
         checkEmpty(checked);
         final List mixedList = Arrays.asList("1", 2, "3");