public static String generateSingleColumnFilter()

in athena-dynamodb/src/main/java/com/amazonaws/athena/connectors/dynamodb/util/DDBPredicateUtils.java [194:288]
82 lines of code
22 McCabe index (conditional complexity)

    public static String generateSingleColumnFilter(String originalColumnName, ValueSet predicate, List<AttributeValue> accumulator,
            IncrementingValueNameProducer valueNameProducer, DDBRecordMetadata recordMetadata)
    {
        String columnName = aliasColumn(originalColumnName);

        if (predicate.isNone()) {
            return "(attribute_not_exists(" + columnName + ") OR " + toPredicate(originalColumnName, "=", null, accumulator, valueNameProducer.getNext(), recordMetadata) + ")";
        }

        if (predicate.isAll()) {
            return "(attribute_exists(" + columnName + ") AND " + toPredicate(originalColumnName, "<>", null, accumulator, valueNameProducer.getNext(), recordMetadata) + ")";
        }

        List<String> disjuncts = new ArrayList<>();
        List<Object> singleValues = new ArrayList<>();
        boolean isWhitelist = true;
        if (predicate instanceof SortedRangeSet) {
            for (Range range : predicate.getRanges().getOrderedRanges()) {
                checkState(!range.isAll()); // Already checked
                if (range.isSingleValue()) {
                    singleValues.add(range.getLow().getValue());
                }
                else {
                    List<String> rangeConjuncts = new ArrayList<>();
                    if (!range.getLow().isLowerUnbounded()) {
                        switch (range.getLow().getBound()) {
                            case ABOVE:
                                rangeConjuncts.add(toPredicate(originalColumnName, ">", range.getLow().getValue(), accumulator, valueNameProducer.getNext(), recordMetadata));
                                break;
                            case EXACTLY:
                                rangeConjuncts.add(toPredicate(originalColumnName, ">=", range.getLow().getValue(), accumulator, valueNameProducer.getNext(), recordMetadata));
                                break;
                            case BELOW:
                                throw new IllegalArgumentException("Low marker should never use BELOW bound");
                            default:
                                throw new AssertionError("Unhandled lower bound: " + range.getLow().getBound());
                        }
                    }
                    if (!range.getHigh().isUpperUnbounded()) {
                        switch (range.getHigh().getBound()) {
                            case ABOVE:
                                throw new IllegalArgumentException("High marker should never use ABOVE bound");
                            case EXACTLY:
                                rangeConjuncts.add(toPredicate(originalColumnName, "<=", range.getHigh().getValue(), accumulator, valueNameProducer.getNext(), recordMetadata));
                                break;
                            case BELOW:
                                rangeConjuncts.add(toPredicate(originalColumnName, "<", range.getHigh().getValue(), accumulator, valueNameProducer.getNext(), recordMetadata));
                                break;
                            default:
                                throw new AssertionError("Unhandled upper bound: " + range.getHigh().getBound());
                        }
                    }
                    // If rangeConjuncts is null, then the range was ALL, which should already have been checked for
                    checkState(!rangeConjuncts.isEmpty());
                    disjuncts.add("(" + AND_JOINER.join(rangeConjuncts) + ")");
                }
            }
        }
        else {
            EquatableValueSet equatablePredicate = (EquatableValueSet) predicate;
            isWhitelist = equatablePredicate.isWhiteList();
            long valueCount = equatablePredicate.getValueBlock().getRowCount();
            for (int i = 0; i < valueCount; i++) {
                singleValues.add(equatablePredicate.getValue(i));
            }
        }

        // Add back all of the possible single values either as an equality or an IN predicate
        if (singleValues.size() == 1) {
            disjuncts.add(toPredicate(originalColumnName, isWhitelist ? "=" : "<>", getOnlyElement(singleValues), accumulator, valueNameProducer.getNext(), recordMetadata));
        }
        else if (singleValues.size() > 1) {
            for (Object value : singleValues) {
                bindValue(originalColumnName, value, accumulator, recordMetadata);
            }
            String values = COMMA_JOINER.join(Stream.generate(valueNameProducer::getNext).limit(singleValues.size()).collect(toImmutableList()));
            disjuncts.add((isWhitelist ? "" : "NOT ") + columnName + " IN (" + values + ")");
        }

        // at this point we should have some disjuncts
        checkState(!disjuncts.isEmpty());

        // add nullability disjuncts
        if (predicate.isNullAllowed()) {
            disjuncts.add("attribute_not_exists(" + columnName + ") OR " +
                    toPredicate(originalColumnName, "=", null, accumulator, valueNameProducer.getNext(), recordMetadata));
        }

        // DDB doesn't like redundant parentheses
        if (disjuncts.size() == 1) {
            return disjuncts.get(0);
        }

        return "(" + OR_JOINER.join(disjuncts) + ")";
    }