private Headers createHeaders()

in src/main/java/org/apache/commons/csv/CSVParser.java [476:540]
59 lines of code
18 McCabe index (conditional complexity)

    private Headers createHeaders() throws IOException {
        Map<String, Integer> hdrMap = null;
        List<String> headerNames = null;
        final String[] formatHeader = this.format.getHeader();
        if (formatHeader != null) {
            hdrMap = createEmptyHeaderMap();
            String[] headerRecord = null;
            if (formatHeader.length == 0) {
                // read the header from the first line of the file
                final CSVRecord nextRecord = this.nextRecord();
                if (nextRecord != null) {
                    headerRecord = nextRecord.values();
                    headerComment = nextRecord.getComment();
                }
            } else {
                if (this.format.getSkipHeaderRecord()) {
                    final CSVRecord nextRecord = this.nextRecord();
                    if (nextRecord != null) {
                        headerComment = nextRecord.getComment();
                    }
                }
                headerRecord = formatHeader;
            }

            // build the name to index mappings
            if (headerRecord != null) {
                // Track an occurrence of a null, empty or blank header.
                boolean observedMissing = false;
                for (int i = 0; i < headerRecord.length; i++) {
                    final String header = headerRecord[i];
                    final boolean blankHeader = CSVFormat.isBlank(header);
                    if (blankHeader && !this.format.getAllowMissingColumnNames()) {
                        throw new IllegalArgumentException(
                            "A header name is missing in " + Arrays.toString(headerRecord));
                    }

                    final boolean containsHeader = blankHeader ? observedMissing : hdrMap.containsKey(header);
                    final DuplicateHeaderMode headerMode = this.format.getDuplicateHeaderMode();
                    final boolean duplicatesAllowed = headerMode == DuplicateHeaderMode.ALLOW_ALL;
                    final boolean emptyDuplicatesAllowed = headerMode == DuplicateHeaderMode.ALLOW_EMPTY;

                    if (containsHeader && !duplicatesAllowed && !(blankHeader && emptyDuplicatesAllowed)) {
                        throw new IllegalArgumentException(
                            String.format(
                                "The header contains a duplicate name: \"%s\" in %s. If this is valid then use CSVFormat.Builder.setDuplicateHeaderMode().",
                                header, Arrays.toString(headerRecord)));
                    }
                    observedMissing |= blankHeader;
                    if (header != null) {
                        hdrMap.put(header, Integer.valueOf(i));
                        if (headerNames == null) {
                            headerNames = new ArrayList<>(headerRecord.length);
                        }
                        headerNames.add(header);
                    }
                }
            }
        }
        if (headerNames == null) {
            headerNames = Collections.emptyList(); // immutable
        } else {
            headerNames = Collections.unmodifiableList(headerNames);
        }
        return new Headers(hdrMap, headerNames);
    }