@Override
    public int hashCode() {
        return timerTask != null ? timerTask.hashCode() : 0;
    }
unwrap to original/unwrapped {@link TimerTask}.

@see TtlUnwrap#unwrap(Object)
@since 2.11.4
ttl2-compatible/src/main/java/com/alibaba/ttl/TtlTimerTask.java