public static Map<Bytes32, Bytes32> generateAllRanges(final int sizeRange) {
    if (sizeRange == 1) {
      return Map.ofEntries(Map.entry(MIN_RANGE, MAX_RANGE));
    }
    return generateRanges(
        MIN_RANGE.toUnsignedBigInteger(), MAX_RANGE.toUnsignedBigInteger(), sizeRange);
  }
This class helps to generate ranges according to several parameters (the start and the end of the
range, its size)
ethereum/trie/src/main/java/org/hyperledger/besu/ethereum/trie/RangeManager.java