apache/iceberg · error · IllegalArgumentException

Unexpected object type for TIME logical type. Received:

Error message

Unexpected object type for TIME logical type. Received:

What it means

convertToTime throws IllegalArgumentException when the object for an Avro TIME logical type is neither java.time.LocalTime (read via MILLI_OF_DAY) nor a Joda-convertible object (with Joda-Time on classpath), so millis-of-day cannot be extracted.

Source

Thrown at flink/v2.3/flink/src/main/java/org/apache/iceberg/flink/formats/avro/AvroToRowDataConverters.java:284

      } else {
        throw new IllegalArgumentException(
            "Unexpected object type for DATE logical type. Received: " + object);
      }
    }
  }

  private static int convertToTime(Object object) {
    final int millis;
    if (object instanceof Integer) {
      millis = (Integer) object;
    } else if (object instanceof LocalTime) {
      millis = ((LocalTime) object).get(ChronoField.MILLI_OF_DAY);
    } else {
      JodaConverter jodaConverter = JodaConverter.getConverter();
      if (jodaConverter != null) {
        millis = jodaConverter.convertTime(object);
      } else {
        throw new IllegalArgumentException(
            "Unexpected object type for TIME logical type. Received: " + object);
      }
    }
    return millis;
  }

  private static byte[] convertToBytes(Object object) {
    if (object instanceof GenericFixed) {
      return ((GenericFixed) object).bytes();
    } else if (object instanceof ByteBuffer) {
      ByteBuffer byteBuffer = (ByteBuffer) object;
      byte[] bytes = new byte[byteBuffer.remaining()];
      byteBuffer.get(bytes);
      return bytes;
    } else {
      return (byte[]) object;
    }
  }

View on GitHub (pinned to 86d9c8fc54)

Solutions

Ensure the Avro decoder produces java.time.LocalTime for TIME fields
Add joda-time dependency for legacy Joda-encoded data
Pre-convert to millis-of-day before calling the converter

Example fix

// before
int millis = convertToTime(legacyDateObject); // throws
// after
int millis = convertToTime(LocalTime.ofInstant(legacyDateObject.toInstant(), ZoneOffset.UTC));

Defensive patterns

Strategy: type-guard

Validate before calling

if (!(object instanceof LocalTime) && !isJodaTime(object)) { throw new IllegalArgumentException("Expected LocalTime for TIME field, got " + object.getClass()); }

Type guard

boolean isTimeDatum(Object o) { return o instanceof LocalTime || o instanceof org.joda.time.LocalTime; }

Try / catch

try { return convertToTime(object); } catch (IllegalArgumentException e) { log.error("Bad TIME datum class: {}", object.getClass()); throw e; }

Prevention

Verify the Avro time-millis/time-micros decoder returns LocalTime
Keep joda-time available for legacy data
Run one end-to-end read of representative data before scaling

When it happens

Trigger: Avro datum for time fields is a java.util.Date, Instant, Long, or other non-LocalTime class; Joda converter null when data holds Joda LocalTime objects.

Common situations: Cross-version Avro data where time is encoded as millis long or util.Date; missing joda-time dependency.

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

AI-assisted analysis of apache/iceberg@86d9c8fc54 (2026-09-12). Data as JSON: /api/errors/3d708146f7dc33d0. Report an issue: GitHub.