static Serializable indexToValue()

in runtime/common/src/main/java/org/apache/nemo/runtime/common/metric/MetricUtils.java [380:434]
54 lines of code
13 McCabe index (conditional complexity)

  static Serializable indexToValue(final Double split, final Double tweak, final Integer epKeyIndex) {
    final Class<? extends Serializable> targetObjectClass = getEpPairFromKeyIndex(epKeyIndex).right();
    final boolean splitIsInteger = split.compareTo((double) split.intValue()) == 0;
    final Pair<Integer, Integer> splitIntVal = splitIsInteger
      ? Pair.of(split.intValue() - 1, split.intValue() + 1)
      : Pair.of(split.intValue(), split.intValue() + 1);

    if (targetObjectClass.isEnum()) {
      final int ordinal;
      if (split < 0) {
        ordinal = 0;
      } else {
        final int maxOrdinal = targetObjectClass.getFields().length - 1;
        final int left = splitIntVal.left() <= 0 ? 0 : splitIntVal.left();
        final int right = splitIntVal.right() >= maxOrdinal ? maxOrdinal : splitIntVal.right();
        ordinal = tweak < 0 ? left : right;
      }
      LOG.info("Translated: {} into ENUM with ordinal {}", split, ordinal);
      return targetObjectClass.getEnumConstants()[ordinal];
    } else if (targetObjectClass.isAssignableFrom(Integer.class)) {
      final Double val = split + tweak + 0.5;
      final Integer res = val.intValue();
      LOG.info("Translated: {} into INTEGER of {}", split, res);
      return res;
    } else if (targetObjectClass.isAssignableFrom(Boolean.class)) {
      final Boolean res;
      if (split < 0) {
        res = false;
      } else if (split > 1) {
        res = true;
      } else {
        final Boolean left = splitIntVal.left() >= 1;  // false by default, true if >= 1
        final Boolean right = splitIntVal.right() > 0;  // true by default, false if <= 0
        res = tweak < 0 ? left : right;
      }
      LOG.info("Translated: {} into BOOLEAN of {}", split, res);
      return res;
    } else {
      final Supplier<IntStream> valueCandidates = () -> EP_METADATA.keySet().stream()
        .filter(p -> p.left().equals(epKeyIndex))
        .mapToInt(Pair::right);
      final Integer left = valueCandidates.get()
        .filter(n -> n < split)
        .map(n -> -n).sorted().map(n -> -n)  // maximum among smaller values
        .findFirst().orElse(valueCandidates.get().min().getAsInt());
      final Integer right = valueCandidates.get()
        .filter(n -> n > split)
        .sorted()  // minimum among larger values
        .findFirst().orElse(valueCandidates.get().max().getAsInt());
      final Integer targetValue = tweak < 0 ? left : right;
      final Serializable res = EP_METADATA.get(Pair.of(epKeyIndex, targetValue)).getValue();
      LOG.info("Translated: {} into VALUE of {}", split, res);
      return res;
    }
  }