docs: public boolean containsKey(final int key)
      {
          boolean found = false;
          @DoNotSub final int setNumber = Hashing.hash(key, mask);
          @DoNotSub final int setBeginIndex = setNumber << setSizeShift;
  
          for (@DoNotSub int i = setBeginIndex, setEndIndex = setBeginIndex + setSize; i < setEndIndex; i++)
          {
              if (null == values[i])
              {
                  break;
              }
  
              if (key == keys[i])
              {
                  found = true;
                  break;
              }
          }
  
          return found;
      }