isDestroyed
Acknowledges physical destruction after a successful close request without waiting or issuing work.
The default is valid only for adapters that destroy all owned resources synchronously during close. Asynchronous adapters report true only after their actual native destruction callbacks complete. A true result is permanent and permits the owner to forget this resource once its whole set is destroyed.
Return
whether every native allocation owned by this resource has been physically destroyed.
Throws
when destruction cannot be established; the owner keeps the resource and its permit.