code: private final java.util.Map getSubMap(final Object key)
      {
          // Defend against systematically changing hashcodes, for examples where consecutive
          // Integers are presented as keys. If we dont shuffle the hashcode then we may get a
          // bunch of requests that hit the same submap.
          int index = key.hashCode();
          index += ~(index << 8);
          index ^= (index >>> 9);
          // Index must be positive.
          index &= 0X7FFFFFFF;
          index = index % subMaps.length;
          if (gatherStatistics)
              subMapAccessFrequency[index]++;
          return subMaps[index];
          // return subMaps[new java.util.Random(key.hashCode()).nextInt(subMaps.length)];
      }
docs: /*
  Compute the subMap containing a key.
  
  @param key for which the subMap to be found.
  
  @return java.util.Map which could contain the key.