Migrating EBCDIC Data Files When Moving from COBOL to Java and C#

Mainframe systems often use the EBCDIC character set to store data files. During a COBOL to Java or C# migration, it is sometimes necessary to convert sequential files between EBCDIC and ASCII formats.

In some cases, organizations may prefer for the translated Java or C# applications to continue working with EBCDIC files for a limited time while the new environment stabilizes.

This page explains the issues involved in handling EBCDIC data and provides solutions for safe, reliable character set conversion during modernization.

Case Study: ING Bank migrates from CICS COBOL (and EBCDIC data files) to Java Cloud

Complications Introduced by Packed Decimal Fields

Packed Decimal (PD) fields use the same binary representation in both ASCII and EBCDIC. During conversion, these fields must be excluded to avoid corrupting data. The conversion process must therefore know the exact position and length of each PD field.

Standard file transfer tools, such as FTP with automatic character conversion, do not account for these fields and may produce incorrect results.

Solution 1: Using SoftwareMining's EbcdicConvertor

SoftwareMining's EbcdicConvertor solves this problem by tracking the position of Packed Decimal fields during character set conversion. The tool offers two modes of operation:

Mode 1: Using Data Access Objects (DAOs)
SoftwareMining's COBOL to Java/C# translator generates Object Relational DAOs for every 01 level structure in the COBOL data division. These DAOs store field size and position information, allowing EbcdicConvertor to convert all fields except Packed Decimal ones. It also supports structures with REDEFINES and OCCURS DEPENDING.

Example:
```
> java com.softwaremining.jcl.EbcdicConvertor e2a com.poc.CustomerRecord infile.txt outfile.txt
```
Mode 2: Using Structure Definitions at Runtime
When a DAO is unavailable or the structure is unknown, record definitions can be supplied as runtime arguments. This allows precise control of which fields to convert and which to skip.

Example:
```
> java com.softwaremining.jcl.EbcdicConvertor e2a (1,20,CH,21,4,PD,24,60,CH) infile.txt outfile.txt
```

Solution 2: Working Directly with EBCDIC Files

By default, translated Java or C# applications use UTF-based character sets for reading, writing, displaying, and logging data. However, the SoftwareMining runtime system can be configured to use different character sets for each operation.

This flexibility allows organizations to continue using EBCDIC for sequential file access while using UTF for databases, screens, and logs. It enables a smooth transition to full modernization without disrupting existing processes.

Reliable EBCDIC Handling During COBOL Modernization

Converting from EBCDIC to ASCII is not as simple as changing encoding; it requires awareness of field structures and binary formats. SoftwareMining's EbcdicConvertor provides an accurate, enterprise-grade solution for handling EBCDIC data during COBOL to Java or C# migration.

Learn more about COBOL data and file handling features

Migrating EBCDIC Data Files When Moving from COBOL to Java and C#

Complications Introduced by Packed Decimal Fields

Solution 1: Using SoftwareMining's EbcdicConvertor

Solution 2: Working Directly with EBCDIC Files

Reliable EBCDIC Handling During COBOL Modernization

Mainframe COBOL Migration Related Papers