@Override
    public boolean isDisposed() {
        return UPDATER.get(this) == COMPLETE;
    }
@author youngjin.kim2

Ensure delegated disposable is run at least once.
<br>
Even if the delegated disposable is set after the DeferredDisposable is disposed,
the delegated disposable is executed.
channel/src/main/java/com/navercorp/pinpoint/channel/reactor/DeferredDisposable.java