private static List<RequirementBasedColumnKey> getRequirements(
      ViewDefinition viewDefinition, EnumSet<ComputationTargetType> targetTypes) {
    List<RequirementBasedColumnKey> result = new ArrayList<RequirementBasedColumnKey>();
    for (ViewCalculationConfiguration calcConfig :
        viewDefinition.getAllCalculationConfigurations()) {
      String calcConfigName = calcConfig.getName();
      if (targetTypes.contains(ComputationTargetType.POSITION)
          || targetTypes.contains(ComputationTargetType.PORTFOLIO_NODE)) {
        for (Pair<String, ValueProperties> portfolioOutput :
            calcConfig.getAllPortfolioRequirements()) {
          String valueName = portfolioOutput.getFirst();
          ValueProperties constraints = portfolioOutput.getSecond();
          RequirementBasedColumnKey columnKey =
              new RequirementBasedColumnKey(calcConfigName, valueName, constraints);
          result.add(columnKey);
        }
      }

      for (ValueRequirement specificRequirement : calcConfig.getSpecificRequirements()) {
        if (!targetTypes.contains(specificRequirement.getTargetSpecification().getType())) {
          continue;
        }
        String valueName = specificRequirement.getValueName();
        ValueProperties constraints = specificRequirement.getConstraints();
        RequirementBasedColumnKey columnKey =
            new RequirementBasedColumnKey(calcConfigName, valueName, constraints);
        result.add(columnKey);
      }
    }
    return result;
  }