code: @SuppressWarnings("unchecked")
      static final <K,V> HashEntry<K,V> entryForHash(Segment<K,V> seg, int h) {
          HashEntry<K,V>[] tab;
          return (seg == null || (tab = seg.table) == null) ? null :
              (HashEntry<K,V>) UNSAFE.getObjectVolatile
              (tab, ((long)(((tab.length - 1) & h)) << TSHIFT) + TBASE);
      }
docs: Gets the table entry for the given segment and hash