* function for most uses, but the virtualized form is needed within retryUpdate.
   *
   * @param currentValue the current value (of either base or a cell)
   * @param newValue the argument from a user update call
   * @return result of the update function
   */
  abstract long fn(long currentValue, long newValue);

  /**
   * Handles cases of updates involving initialization, resizing, creating new Cells, and/or

  // within a given metric.
  // +optional
  optional .k8s.io.apimachinery.pkg.apis.meta.v1.LabelSelector metricSelector = 2;

  // currentValue is the current value of the metric (as a quantity)
  optional .k8s.io.apimachinery.pkg.api.resource.Quantity currentValue = 3;

  // currentAverageValue is the current value of metric averaged over autoscaled pods.
  // +optional

   * function for most uses, but the virtualized form is needed within retryUpdate.
   *
   * @param currentValue the current value (of either base or a cell)
   * @param newValue the argument from a user update call
   * @return result of the update function
   */
  abstract long fn(long currentValue, long newValue);

  /**
   * Handles cases of updates involving initialization, resizing, creating new Cells, and/or

      local = Optional.absent();
      for (String currentValue : parameters.get(CHARSET_ATTRIBUTE)) {
        if (value == null) {
          value = currentValue;
          local = Optional.of(Charset.forName(value));
        } else if (!value.equals(currentValue)) {
          throw new IllegalStateException(
              "Multiple charset values defined: " + value + ", " + currentValue);
        }
      }
      parsedCharset = local;

		`MetricName:` + fmt.Sprintf("%v", this.MetricName) + `,`,
		`MetricSelector:` + strings.Replace(fmt.Sprintf("%v", this.MetricSelector), "LabelSelector", "v1.LabelSelector", 1) + `,`,
		`CurrentValue:` + strings.Replace(strings.Replace(fmt.Sprintf("%v", this.CurrentValue), "Quantity", "resource.Quantity", 1), `&`, ``, 1) + `,`,
		`CurrentAverageValue:` + strings.Replace(fmt.Sprintf("%v", this.CurrentAverageValue), "Quantity", "resource.Quantity", 1) + `,`,

      local = Optional.absent();
      for (String currentValue : parameters.get(CHARSET_ATTRIBUTE)) {
        if (value == null) {
          value = currentValue;
          local = Optional.of(Charset.forName(value));
        } else if (!value.equals(currentValue)) {
          throw new IllegalStateException(
              "Multiple charset values defined: " + value + ", " + currentValue);
        }
      }
      parsedCharset = local;

                void count(String name) {
                    def service = evaluationCountService.get()
                    service."\${name}"()
                    def currentValue = service."\${name}Count"
                    println "Evaluating \${name} \${currentValue}"
                }

                class NestedBean {
                    @Input getFirst() {
                        count("nestedInputValue")

		`MetricName:` + fmt.Sprintf("%v", this.MetricName) + `,`,
		`MetricSelector:` + strings.Replace(fmt.Sprintf("%v", this.MetricSelector), "LabelSelector", "v1.LabelSelector", 1) + `,`,
		`CurrentValue:` + strings.Replace(strings.Replace(fmt.Sprintf("%v", this.CurrentValue), "Quantity", "resource.Quantity", 1), `&`, ``, 1) + `,`,
		`CurrentAverageValue:` + strings.Replace(fmt.Sprintf("%v", this.CurrentAverageValue), "Quantity", "resource.Quantity", 1) + `,`,

							Ref:         ref("k8s.io/apimachinery/pkg/apis/meta/v1.LabelSelector"),
						},
					},
					"currentValue": {
						SchemaProps: spec.SchemaProps{
							Description: "currentValue is the current value of the metric (as a quantity)",
							Ref:         ref("k8s.io/apimachinery/pkg/api/resource.Quantity"),
						},
					},
					"currentAverageValue": {

            read(decoder)
        }
        store.createValueStore(stateType, writer, reader)
    }

    private
    val previousValues = ConcurrentHashMap<K, BlockAddress>()

    private
    val currentValues = ConcurrentHashMap<K, CalculatedValueContainer<BlockAddress, *>>()

    protected
    abstract fun projectPathForKey(key: K): Path?

    protected
    abstract fun write(encoder: Encoder, value: V)