pentaho/pentaho-kettle · error · KettleException

java.lang.NullPointerException (wrapped; row too short for…

Error message

java.lang.NullPointerException (wrapped; row too short for index)

What it means

In CsvInputAwareHelper.getStringFromRow, when failOnParseError is true and the requested index exceeds the row's length, a raw NullPointerException is thrown wrapped in a KettleException. The empty NPE gives no message, but the semantic is 'row too short for the requested field index'.

Solutions

1. Remove/pre-filter blank or truncated lines from the input file
2. Check the step's header-line and field-count settings against the actual file
3. Enable error handling for the step so short rows go to an error stream instead of failing
4. Read the KettleException's cause (NullPointerException) as the signal that index exceeded row length

Example fix

// before
file.csv last line: 'a,b'
// step defines 3 fields -> row too short
// after
ensure every data line has all fields:
'a,b,'
or filter empty lines with a 'Filter rows' step on field1 <> ''

// check each line's column count before processing
String[] cols = line.split(",", -1);
if (cols.length < expectedFieldCount) skipBlankLine(line);

boolean rowHasField(Object[] row, int index) {
  return row != null && row.length > index;
}

try { string = helper.getStringFromRow(row, index, false); }
catch (KettleException e) { if (e.getCause() instanceof NullPointerException) logError("Row too short: " + row.length); throw e; }

When it happens

Trigger: row.length <= index and failOnParseError is true — the physical row has fewer columns than the defined field count (e.g. trailing empty line or truncated record).

Common situations: CSV files with blank trailing lines, ragged rows with missing trailing delimiters, wrong 'N of header lines' settings, or files where the last line lacks a newline and is mis-split.

Related errors

• CsvInput.Exception.ErrorPreparingParallelRun
• e.getMessage() (first conversion cause, no own message)
• exc (wraps parse exception, no own message)
• AccessInputMeta.Exception.ErrorSavingToRepository
• AccessInputMeta.Exception.FileDoesNotExist

AI-assisted analysis of pentaho/pentaho-kettle@f3058517a1 (2026-09-13). Data as JSON: /api/errors/a10775fc81b0b112. Report an issue: GitHub.

Appendix: source

Thrown at engine/src/main/java/org/pentaho/di/trans/steps/common/CsvInputAwareHelper.java:200

    } catch ( final Exception e ) {
      exc = e;
    }

    // if 'failOnParseError' is true, and we caught an exception, we either re-throw the exception, or wrap its as a
    // KettleException, if it isn't one already
    if ( failOnParseError ) {
      if ( exc instanceof KettleException ) {
        throw (KettleException) exc;
      } else if ( exc != null ) {
        throw new KettleException( exc );
      }
    }

    // if 'failOnParseError' is false, or there is no exception otherwise, we get the string value straight from the row
    // object
    if ( string == null ) {
      if ( ( row.length <= index ) && failOnParseError ) {
        throw new KettleException( new NullPointerException() );
      }
      string = row.length <= index || row[ index ] == null ? null : row[ index ].toString();
    }

    return string;
  }

  /**
   * Creates a buffered input stream reader for the given CSV input metadata and input stream.
   *
   * @param meta        the CSV input metadata
   * @param inputStream the input stream to read from
   * @return a BufferedInputStreamReader for reading the CSV file
   */
  default BufferedInputStreamReader getBufferedReader( final TransMeta transMeta, final CsvInputAwareMeta meta,
                                                       final InputStream inputStream ) {
    return new BufferedInputStreamReader( getReader( transMeta, meta, inputStream ) );
  }

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