apache/seatunnel · error · UnsupportedOperationException

Unsupported convert to Short

Error message

Unsupported convert ${value.getClass()} to Short

What it means

Thrown by BasicDataConverter.convertShort(Object value) when the value is neither a Number nor a String. It is the typeDefine-less variant of error 106, and the message reports the unexpected class that could not be narrowed to a short.

Solutions

1. Pre-convert the value (parse String, box Boolean to 0/1, decode byte[]) before calling convertShort
2. Update the catalog type to match the real data type
3. Override convertShort(Object) in a custom converter to handle the missing branch

Example fix

// before
short s = converter.convertShort(row.getField(0)); // Boolean throws
// after
Object v = row.getField(0);
short s = (v instanceof Boolean) ? ((Boolean) v ? (short) 1 : (short) 0) : converter.convertShort(v);

Object v = row.getField(0);
if (!(v instanceof Number) && !(v instanceof String)) {
    throw new IllegalArgumentException("Value " + v.getClass() + " cannot be converted to short");
}

static boolean isShortConvertible(Object v) {
    return v instanceof Number || v instanceof String;
}

try {
    s = converter.convertShort(value);
} catch (UnsupportedOperationException e) {
    LOG.warn("Cannot convert {} to short", value.getClass());
    s = 0;
}

When it happens

Trigger: Calling the convertShort(Object) overload with Boolean, byte[], LocalDate or arbitrary objects while expecting a SMALLINT value.

Common situations: Direct use of the convenience overload in custom code; untyped Object rows from generic deserializers; schema drift between source field types and sink SMALLINT columns.

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

• Unsupported convert to Boolean, typeDefine
• Unsupported convert to Boolean
• Unsupported convert to Byte
• Unsupported convert to Byte, typeDefine
• Unsupported convert to Float, typeDefine

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/4258db7f66c0e76b. Report an issue: GitHub.

Appendix: source

Thrown at seatunnel-api/src/main/java/org/apache/seatunnel/api/table/converter/BasicDataConverter.java:1213

    default short convertShort(T typeDefine, Number value) {
        return convertShort(value);
    }

    default short convertShort(T typeDefine, String value) {
        return convertShort(value);
    }

    default short convertShort(Object value) throws UnsupportedOperationException {
        if (value instanceof Short) {
            return (short) value;
        }
        if (value instanceof Number) {
            return convertShort((Number) value);
        }
        if (value instanceof String) {
            return convertShort((String) value);
        }
        throw new UnsupportedOperationException(
                "Unsupported convert " + value.getClass() + " to Short");
    }

    default short convertShort(Number value) {
        return value.shortValue();
    }

    default short convertShort(String value) {
        return Short.parseShort(value);
    }

    default byte convertByte(T typeDefine, Object value) throws UnsupportedOperationException {
        if (value instanceof Byte) {
            return (byte) value;
        }
        if (value instanceof Number) {
            return convertByte(typeDefine, (Number) value);
        }

View on GitHub (pinned to cf67b549a7)