apache/iceberg · error · UnsupportedOperationException

Unsupported type: float

Error message

Unsupported type: float

What it means

The base ArrowVectorAccessor.getFloat(int) is an unimplemented stub that always throws. Float (float4) vector accessors must override it; invoking the base means the accessor for this vector does not support float extraction. toFloat4Vector in the vectorized readers depends on an overriding subclass.

Source

Thrown at arrow/src/main/java/org/apache/iceberg/arrow/vectorized/ArrowVectorAccessor.java:65

      }
    }
    vector.close();
  }

  public boolean getBoolean(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: boolean");
  }

  public int getInt(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: int");
  }

  public long getLong(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: long");
  }

  public float getFloat(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: float");
  }

  public double getDouble(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: double");
  }

  public byte[] getBinary(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: binary");
  }

  public DecimalT getDecimal(int rowId, int precision, int scale) {
    throw new UnsupportedOperationException("Unsupported type: decimal");
  }

  public Utf8StringT getUTF8String(int rowId) {
    throw new UnsupportedOperationException("Unsupported type: UTF8String");
  }

View on GitHub (pinned to 86d9c8fc54)

Solutions

1. Use a Float4-backed accessor subclass that overrides getFloat to return vector.get(rowId).
2. Override getFloat in your subclass.
3. Verify the accessor factory dispatches Float4Vector to the float accessor.

Example fix

// before
class MyAccessor extends ArrowVectorAccessor<Float4Vector> { } // getFloat missing
// after
@Override public float getFloat(int rowId) { return vector.get(rowId); }

if (!(accessor instanceof FloatAccessor)) { /* fallback */ }

static boolean supportsFloat(ArrowVectorAccessor<?> a) {
  return a.getClass() != ArrowVectorAccessor.class;
}

try {
  float v = accessor.getFloat(rowId);
} catch (UnsupportedOperationException e) {
  if ("Unsupported type: float".equals(e.getMessage())) { fallbackRead(rowId); } else { throw e; }
}

When it happens

Trigger: Reading a float column through a non-float accessor or the raw base class; factory code that maps float vectors to a generic accessor.

Common situations: Custom readers converting Arrow batches to engine vectors (toFloat4Vector path) with a mis-mapped accessor; subclass written without the float override.

Related errors

• Cannot read unsupported column types:
• Unsupported type: boolean
• Unsupported type: int
• Unsupported type: long
• Unsupported type: double

AI-assisted analysis of apache/iceberg@86d9c8fc54 (2026-09-12). Data as JSON: /api/errors/e5b3504eac6c7f12. Report an issue: GitHub.