checkNotNull(cell.getValue(), "value");
        @SuppressWarnings("unchecked") // all supported methods are covariant
        Cell<R, C, V> immutableCell = (Cell<R, C, V>) cell;
        cells.add(immutableCell);
      } else {
        put(cell.getRowKey(), cell.getColumnKey(), cell.getValue());
      }
      return this;
    }

    /**

// Atomically increments the value of the cell. The value must be non-negative.
TF_CAPI_EXPORT extern void TFE_MonitoringCounterCellIncrementBy(
    TFE_MonitoringCounterCell* cell, int64_t value);

// Retrieves the current value of the cell.
TF_CAPI_EXPORT extern int64_t TFE_MonitoringCounterCellValue(
    TFE_MonitoringCounterCell* cell);

// APIs for Counter without label.

   */
  @Override
  public Set<Cell<R, C, @Nullable V>> cellSet() {
    return super.cellSet();
  }

  @Override
  Iterator<Cell<R, C, @Nullable V>> cellIterator() {
    return new AbstractIndexedListIterator<Cell<R, C, @Nullable V>>(size()) {
      @Override
      protected Cell<R, C, @Nullable V> get(final int index) {
        return getCell(index);
      }
    };

   */
  @Override
  public Set<Cell<R, C, @Nullable V>> cellSet() {
    return super.cellSet();
  }

  @Override
  Iterator<Cell<R, C, @Nullable V>> cellIterator() {
    return new AbstractIndexedListIterator<Cell<R, C, @Nullable V>>(size()) {
      @Override
      protected Cell<R, C, @Nullable V> get(final int index) {
        return getCell(index);
      }
    };

      }
    }
  }

  public void testKnownUtf8Hashing() {
    for (Cell<HashFunction, String, String> cell : KNOWN_HASHES.cellSet()) {
      HashFunction func = cell.getRowKey();
      String input = cell.getColumnKey();
      String expected = cell.getValue();
      assertEquals(
          String.format(Locale.ROOT, "Known hash for hash(%s, UTF_8) failed", input),

                "id": "links",
                "value": [
                  {
                    "targetBlank": false,
                    "title": "$__cell dashboard",
                    "url": "/dashboard/db/istio-workload-dashboard?var-workload=${__cell_2:raw}&var-namespace=${__cell_3:raw}"
                  }
                ]
              },
              {
                "id": "custom.align"
              }

- we also seem to have artifact information tangled inside the plugin model
- we have to deal with scripting implementations (groovy, beanshell, ruby)
- we need to deal with a shared context for plugins, like the guarded mojos
- we need to deal with plugins as core application logic which can also interact with plugins

* Along with this comes the testing strategies that make this work

  CHECK_EQ(TF_OK, TF_GetCode(status)) << TF_Message(status);
  TF_DeleteStatus(status);
  auto* cell = TFE_MonitoringGetCellCounter0(counter);
  TFE_MonitoringCounterCellIncrementBy(cell, 1);
  EXPECT_EQ(TFE_MonitoringCounterCellValue(cell), 1);
  auto* collection_registry = monitoring::CollectionRegistry::Default();
  monitoring::CollectionRegistry::CollectMetricsOptions options;

      }
    }
  }

  public void testKnownUtf8Hashing() {
    for (Cell<HashFunction, String, String> cell : KNOWN_HASHES.cellSet()) {
      HashFunction func = cell.getRowKey();
      String input = cell.getColumnKey();
      String expected = cell.getValue();
      assertEquals(
          String.format(Locale.ROOT, "Known hash for hash(%s, UTF_8) failed", input),

   * row, and so on.
   *
   * <p>Each cell is an immutable snapshot of a row key / column key / value mapping, taken at the
   * time the cell is returned by a method call to the set or its iterator.
   */
  @Override
  public Set<Cell<R, C, V>> cellSet() {
    return super.cellSet();
  }

  @Override
  Iterator<Cell<R, C, V>> cellIterator() {
    return new CellIterator();
  }