private static JsonObject processFrequencyQuery()

in src/main/java/org/apache/datasketches/server/DataQueryHandler.java [278:321]
34 lines of code
9 McCabe index (conditional complexity)

  private static JsonObject processFrequencyQuery(final JsonObject result, final JsonObject query, final Family type, final Object sketch) {
    if (query == null || type != Family.FREQUENCY || sketch == null) {
      return null;
    }

    final ItemsSketch<String> sk = (ItemsSketch<String>) sketch;

    // check if we need a summary
    final boolean addSummary = checkSummaryFlag(query);

    if (!query.has(QUERY_ERRORTYPE_FIELD)) {
      throw new SketchesException("Must specify a value for " + QUERY_ERRORTYPE_FIELD
          + " for Frequent Items queries");
    }

    final ErrorType errorType;
    final String errorTypeString = query.get(QUERY_ERRORTYPE_FIELD).getAsString();
    if (errorTypeString.equals(QUERY_ERRORTYPE_NO_FP)) {
      errorType = ErrorType.NO_FALSE_POSITIVES;
    } else if (errorTypeString.equals(QUERY_ERRORTYPE_NO_FN)) {
      errorType = ErrorType.NO_FALSE_NEGATIVES;
    } else {
      throw new SketchesException("Unknown Frequent Items ErrorType: " + errorTypeString);
    }

    final ItemsSketch.Row<String>[] items = sk.getFrequentItems(errorType);

    final JsonArray itemArray = new JsonArray();
    for (final ItemsSketch.Row<String> item : items) {
      final JsonObject row = new JsonObject();
      row.addProperty(RESPONSE_ITEM_VALUE, item.getItem());
      row.addProperty(RESPONSE_ITEM_ESTIMATE, item.getEstimate());
      row.addProperty(RESPONSE_ITEM_UPPER_BOUND, item.getUpperBound());
      row.addProperty(RESPONSE_ITEM_LOWER_BOUND, item.getLowerBound());
      itemArray.add(row);
    }

    //final JsonObject result = new JsonObject();
    result.add(RESPONSE_ITEMS_ARRAY, itemArray);
    if (addSummary)
      result.addProperty(RESPONSE_SUMMARY_FIELD, sk.toString());

    return result;
  }