int expectedModCount = modCount;

        private void checkForComodification() {
          if (modCount != expectedModCount) {
            throw new ConcurrentModificationException();
          }
        }

        @Override
        public boolean hasNext() {
          checkForComodification();
          return nextEntry != null;
        }

        @Override

        int expectedModCount = modCount;

        private void checkForComodification() {
          if (modCount != expectedModCount) {
            throw new ConcurrentModificationException();
          }
        }

        @Override
        public boolean hasNext() {
          checkForComodification();
          return nextEntry != null;
        }

        @Override

        private int remaining = biMap.size;

        private void checkForComodification() {
          if (biMap.modCount != expectedModCount) {
            throw new ConcurrentModificationException();
          }
        }

        @Override
        public boolean hasNext() {
          checkForComodification();
          return index != ENDPOINT && remaining > 0;
        }

        @Override