code: @Override
      public final V get(Object key) {
          long hash, allocIndex;
          Segment<K, V> segment;
          return (allocIndex = (segment = segment(segmentIndex(hash = keyHashCode(key))))
                  .find(this, hash, key)) > 0 ?
                  segment.readValue(allocIndex) : null;
      }
docs: Returns the value to which the specified key is mapped, or {@code null} if this map contains
  no mapping for the key.
  
  <p>More formally, if this map contains a mapping from a key {@code k} to a value {@code v}
  such that {@link #keysEqual(Object, Object) keysEqual(key, k)}{@code == true}, then this
  method returns {@code v}; otherwise it returns {@code null}. (There can be at most one such
  mapping.)
  
  <p>A return value of {@code null} does not <i>necessarily</i> indicate that the map contains
  no mapping for the key; it's also possible that the map explicitly maps the key to {@code
  null}. The {@link #containsKey containsKey} operation may be used to distinguish these two
  cases.
  
  @param key the key whose associated value is to be returned
  @return the value to which the specified key is mapped, or
  {@code null} if this map contains no mapping for the key