code: @NullSafe
    @SuppressWarnings("unchecked")
    protected BloomFilter<T> resolveBloomFilter(int index) {
  
      return Optional.ofNullable(getBloomFilters()[index])
        .orElseGet(() ->
          getBloomFilters()[index] =
            newBloomFilter(getApproximateNumberOfElementsPerFilter(), getAcceptableFalsePositiveRate()));
    }
docs: Resolves the actual {@link BloomFilter} at index used to add or evaluate an element.
  
  @param index integer value representing the index of the {@link BloomFilter} to retrieve.
  @return the {@link BloomFilter} at index.  If the {@link BloomFilter} at index is {@literal null},
  then this method constructs a new {@link BloomFilter} and sets a reference to it at index.
  @see #getApproximateNumberOfElementsPerFilter()
  @see #getAcceptableFalsePositiveRate()
  @see #newBloomFilter(int, float)