apache/beam · error · java.lang.IllegalArgumentException

Could not parse CSV records from

Error message

Could not parse CSV records from %s with format %s

What it means

BeamTableUtils.csvLines2BeamRows wraps IOExceptions from the Commons CSV parser in an IllegalArgumentException indicating the CSV records could not be parsed from the given line with the given format.

Solutions

1. Fix malformed quoting/characters in the CSV data
2. Align CSVFormat settings (delimiter, quote, escape) with the actual file format
3. Pre-validate/sanitize lines before parsing
4. Catch the IllegalArgumentException upstream to log and skip bad records

Example fix

// before
CSVFormat.DEFAULT // data contains embedded quotes
// after
CSVFormat.DEFAULT.withEscape('\\').withQuote('"')

try { rows = BeamTableUtils.csvLines2BeamRows(line, schema, format); } catch (IllegalArgumentException e) { log.error("CSV parse failed: " + line, e); }

When it happens

Trigger: CSVParser.parse/getRecords throwing IOException for the input line under the configured CSVFormat — malformed quoting, invalid characters relative to the format settings, or IO problems reading the parsed content.

Common situations: Unbalanced quotes in CSV fields; mismatched CSVFormat settings (delimiter/escape/quote) versus actual data; corrupt or binary data fed into a CSV pipeline.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

• Error while parsing the element
• Expect fields, but actually
• malformed input for decoding
• A schema is required to write non-schema'd data.
• A sink must inherit iobase.Sink, iobase.NativeSink, or be a…

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/9728c5a30625964a. Report an issue: GitHub.

Appendix: source

Thrown at sdks/java/extensions/sql/src/main/java/org/apache/beam/sdk/extensions/sql/impl/schema/BeamTableUtils.java:86

    if (!line.endsWith(csvFormat.getRecordSeparator())) {
      line += csvFormat.getRecordSeparator();
    }
    try (CSVParser parser = CSVParser.parse(line, csvFormat)) {
      List<Row> rows = new ArrayList<>();
      for (CSVRecord rawRecord : parser.getRecords()) {
        if (rawRecord.size() != schema.getFieldCount()) {
          throw new IllegalArgumentException(
              String.format(
                  "Expect %d fields, but actually %d", schema.getFieldCount(), rawRecord.size()));
        }
        rows.add(
            IntStream.range(0, schema.getFieldCount())
                .mapToObj(idx -> autoCastField(schema.getField(idx), rawRecord.get(idx)))
                .collect(toRow(schema)));
      }
      return rows;
    } catch (IOException e) {
      throw new IllegalArgumentException(
          String.format("Could not parse CSV records from %s with format %s", line, csvFormat), e);
    }
  }

  public static String beamRow2CsvLine(Row row, CSVFormat csvFormat) {
    StringWriter writer = new StringWriter();
    try (CSVPrinter printer = csvFormat.print(writer)) {
      for (int i = 0; i < row.getFieldCount(); i++) {
        printer.print(row.getBaseValue(i, Object.class).toString());
      }
      printer.println();
    } catch (IOException e) {
      throw new IllegalArgumentException("encodeRecord failed!", e);
    }
    return writer.toString();
  }

  /**

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