apache/seatunnel · error · RuntimeException

Cannot convert timestamptz: , type:

Error message

Cannot convert timestamptz: , type: 

What it means

Iceberg RowConverter throws this RuntimeException when a timestamptz (Iceberg TimestampType with adjustToUTC) value cannot be converted to OffsetDateTime. convertOffsetDateTime accepts String (parsed), LocalDateTime, OffsetDateTime, and Date; anything else is rejected with both value and class in the message.

Solutions

1. Convert the value to OffsetDateTime or java.util.Date before the sink.
2. Add a transform CAST(column, TIMESTAMP) so SeaTunnel delivers a supported temporal type.
3. If holding epoch millis, convert: Instant.ofEpochMilli(ms).atOffset(ZoneOffset.UTC).
4. Check source connector timestamp mapping config so timestamps arrive as SeaTunnel TimestampType.

Example fix

// before
writer.write(idx, 1710000000000L); // Long not accepted
// after
writer.write(idx, Instant.ofEpochMilli(1710000000000L).atOffset(ZoneOffset.UTC)); // OffsetDateTime accepted

if (!(v instanceof OffsetDateTime) && !(v instanceof LocalDateTime) && !(v instanceof java.util.Date) && !(v instanceof String)) throw new IllegalArgumentException("timestamptz column must be OffsetDateTime/LocalDateTime/Date/String, got " + (v == null ? "null" : v.getClass().getName()));

boolean isTimestamptzConvertible(Object v) { return v instanceof OffsetDateTime || v instanceof LocalDateTime || v instanceof java.util.Date || v instanceof String; }

try { sink.write(row); } catch (RuntimeException e) { if (e.getMessage() != null && e.getMessage().startsWith("Cannot convert timestamptz")) { /* convert epoch/Instant to OffsetDateTime or DLQ */ } else throw e; }

When it happens

Trigger: convertOffsetDateTime receives an unsupported object (e.g. Long epoch millis, ZonedDateTime, or a nested type) while converting a field for a timestamptz Iceberg column via convertTimestampValue.

Common situations: Sources emitting epoch millis as Long for timestamp columns; JDBC sources returning custom temporal types; CDC formats delivering timestamps in wrapper objects.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

• Cannot convert timestamp: , type:
• Cannot convert date:
• Cannot convert time:
• Cannot convert to BigDecimal:
• Cannot convert to binary:

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/74c9ff439d0e3ba6. Report an issue: GitHub.

Appendix: source

Thrown at seatunnel-connectors-v2/connector-iceberg/src/main/java/org/apache/seatunnel/connectors/seatunnel/iceberg/data/RowConverter.java:441

    private OffsetDateTime convertOffsetDateTime(Object value) {
        if (value instanceof Number) {
            long millis = ((Number) value).longValue();
            return DateTimeUtil.timestamptzFromMicros(millis * 1000);
        } else if (value instanceof String) {
            return parseOffsetDateTime((String) value);
        } else if (value instanceof OffsetDateTime) {
            return (OffsetDateTime) value;
        } else if (value instanceof LocalDateTime) {
            // Convert to OffsetDateTime using the system(jvm) default timezone
            return ((LocalDateTime) value)
                    .atZone(ZoneId.systemDefault())
                    .withZoneSameInstant(ZoneOffset.UTC)
                    .toOffsetDateTime();
        } else if (value instanceof Date) {
            return DateTimeUtil.timestamptzFromMicros(((Date) value).getTime() * 1000);
        }
        throw new RuntimeException(
                "Cannot convert timestamptz: " + value + ", type: " + value.getClass());
    }

    private OffsetDateTime parseOffsetDateTime(String str) {
        String tsStr = ensureTimestampFormat(str);
        try {
            return OFFSET_TS_FMT.parse(tsStr, OffsetDateTime::from);
        } catch (DateTimeParseException e) {
            return LocalDateTime.parse(tsStr, DateTimeFormatter.ISO_LOCAL_DATE_TIME)
                    .atOffset(ZoneOffset.UTC);
        }
    }

    private LocalDateTime convertLocalDateTime(Object value) {
        if (value instanceof Number) {
            long millis = ((Number) value).longValue();
            return DateTimeUtil.timestampFromMicros(millis * 1000);
        } else if (value instanceof String) {

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