code: public int getExistingInt(int key) {
          if (key < 0) Kit.codeBug();
          int index = findIndex(key);
          if (0 <= index) {
              if (ivaluesShift != 0) {
                  return keys[ivaluesShift + index];
              }
              return 0;
          }
          // Key must exist
          Kit.codeBug();
          return 0;
      }
docs: Get integer value assigned with key.
  @return key integer value or defaultValue if key does not exist or does
  not have int value
  @throws RuntimeException if key does not exist