@Override
        public boolean equals(Object o) {
            if (this == o)
                return true;
            if (o == null || getClass() != o.getClass())
                return false;
            Key key = (Key) o;
            return position == key.position && Objects.equals(cacheId, key.cacheId);
        }
Ensure the capacity of cache

@param cacheStartPosition if the eviction entries contain the current cache, then ensure capacity will return null.
@param size               size of data
@return the indexes of cache blocks
core/src/main/scala/kafka/log/streamaspect/cache/FileCache.java