apache/seatunnel · error · IllegalStateException

columnDefine size not match

Error message

columnDefine size not match

What it means

DataConverter.convert(Column[], Function) applies the value producer and then requires that the produced Object[] length equals the number of Column definitions, converting each field with its column. A length mismatch means the row data and the schema are out of sync, so it fails fast with IllegalStateException.

Source

Thrown at seatunnel-api/src/main/java/org/apache/seatunnel/api/table/converter/DataConverter.java:64

        return convert(columnDefine.getDataType(), value);
    }

    default Object convert(T typeDefine, Column columnDefine, Object value) {
        return convert(columnDefine, value);
    }

    default Object[] convert(T[] typeDefine, Column[] columnDefine, Object[] value) {
        for (int i = 0; i < value.length; i++) {
            value[i] =
                    convert(typeDefine != null ? typeDefine[i] : null, columnDefine[i], value[i]);
        }
        return value;
    }

    default Object[] convert(Column[] columnDefine, Function<Column[], Object[]> valueApply) {
        Object[] fields = valueApply.apply(columnDefine);
        if (fields.length != columnDefine.length) {
            throw new IllegalStateException("columnDefine size not match");
        }

        for (int i = 0; i < fields.length; i++) {
            fields[i] = convert(columnDefine[i], fields[i]);
        }
        return fields;
    }

    default Object[] convert(
            T[] typeDefine, Column[] columnDefine, BiFunction<T[], Column[], Object[]> valueApply) {
        boolean hasTypeDefine = typeDefine != null;
        if (hasTypeDefine && typeDefine.length != columnDefine.length) {
            throw new IllegalStateException("typeDefine size not match");
        }

        Object[] fields = valueApply.apply(typeDefine, columnDefine);
        if (fields.length != columnDefine.length) {
            throw new IllegalStateException("columnDefine size not match");

View on GitHub (pinned to cf67b549a7)

Solutions

  1. Rebuild the Column[] schema from the same source that produced the values
  2. Ensure the value producer reads exactly the columns in columnDefine (same order and count)
  3. Check for schema drift between the connector's cached schema and the live source

Example fix

// before
Object[] row = readAllColumns(rs); // 12 values vs 11 columns
// after
Object[] row = new Object[columnDefine.length];
for (int i = 0; i < columnDefine.length; i++) row[i] = rs.getObject(i + 1);
Defensive patterns

Strategy: validation

Validate before calling

Object[] fields = valueApply.apply(columnDefine);
if (fields.length != columnDefine.length) {
    throw new IllegalArgumentException("row has " + fields.length + " fields but schema has " + columnDefine.length);
}

Try / catch

try {
    Object[] out = dataConverter.convert(columnDefine, valueApply);
} catch (IllegalStateException e) {
    log.error("Schema/row mismatch detected: {}", e.getMessage());
    throw e;
}

Prevention

When it happens

Trigger: The Function<Column[], Object[]> passed to convert returns an array whose length differs from columnDefine.length.

Common situations: ResultSet column count changed after schema was built; SELECT list altered; schema derived from a stale/mismatched table definition.

Related errors

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/71f0ce7ddd3ce0c4. Report an issue: GitHub.