@Override
        public T next() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }
            return ready.remove(ready.size() - 1);
        }
Iterate over the values that existed in the hash table during a specific snapshot.

You can use this iterator even if you are making changes to the map.
The snapshot is immutable and will always show up the same.
server-common/src/main/java/org/apache/kafka/timeline/SnapshottableHashTable.java