@Override
    public boolean removeFirstOccurrence(DelayedEntry entry) {
        DelayedEntry removedEntry = deque.pollFirst();
        if (removedEntry == null) {
            return false;
        }
        decreaseCountIndex(entry);
        return true;
    }
@ Override public boolean removeFirstOccurrence ( DelayedEntry entry ) { DelayedEntry removedEntry = deque . pollFirst ( ) ; if ( removedEntry == null ) { return false ; } decreaseCountIndex ( entry ) ; return true ; }
Removes the first element of this queue instead of searching for it,
implementation of this method is strongly tied with {@link StoreWorker} implementation.

@param entry element to be removed.
@return <code>true</code> if removed successfully, <code>false</code> otherwise