--- a/src/java.base/share/classes/java/lang/ref/Reference.java Thu May 03 09:07:40 2018 -0700
+++ b/src/java.base/share/classes/java/lang/ref/Reference.java Thu May 03 11:18:57 2018 -0700
@@ -300,6 +300,20 @@
return this.queue.enqueue(this);
}
+ /**
+ * Throws {@link CloneNotSupportedException}. A {@code Reference} cannot be
+ * meaningfully cloned. Construct a new {@code Reference} instead.
+ *
+ * @returns never returns normally
+ * @throws CloneNotSupportedException always
+ *
+ * @since 11
+ */
+ @Override
+ protected Object clone() throws CloneNotSupportedException {
+ throw new CloneNotSupportedException();
+ }
+
/* -- Constructors -- */
Reference(T referent) {