Invoked after the completion of a send regardless of any exception that
have been raised thus allowing for proper resource cleanup.
<p>Note that this will be invoked only if {@link #preSend} successfully
completed and returned a Message, i.e. it did not return {@code null}.
@since 4.1
Invoked after the completion of a send regardless of any exception that have been raised thus allowing for proper resource cleanup. <p>Note that this will be invoked only if {@link #preSend} successfully completed and returned a Message, i.e. it did not return {@code null}. @since 4.1