# Migration to the COBOL Reader/Writer

Since 7.1, Talend Data Mapper features a complete rework of the COBOL Reader/Writer. If you wish to migrate to the latest version of the COBOL representation, check the implementations.

## Numeric control

The controls on numerics, particularly packed decimals, are now tighter. This implementation may result in failing maps. To fix this issue, new COBOL properties are introduced - Pad decimals on read with leading zeroes, Allow spaces for packed decimals, Allow any character in display decimals. For more information, see [COBOL representation properties](https://help.qlik.com/talend/en-US/data-mapper-user-guide/8.0-R2024-04-and-earlier/cobol-representation-properties).

## Byte array or Input stream

The COBOL reader only accepts either a byte array or an input stream. If you connect a tFileInputRaw set to read data as String and connect a ttHMap with a COBOL Reader configuration, this raises an exception.

Information noteNote: The non-Eclipse runtime support is unavailable for tHConvertFile and cMap.