Mainframe
COBOL to Java, C#
& Cloud
NOTE: Business Rule Extraction is now integrated into the COBOL-to-Java Translation Toolkit.
Legacy COBOL applications handle a wide range of tasks such as transaction processing, database access, and screen management. Because of their size and complexity, identifying which code segments contain true business logic versus supporting operations can be challenging.
Business Rule Extraction (BRE) aims to isolate the COBOL logic that defines business rules. This page explains the benefits and limitations of BRE as a modernization approach, and outlines SoftwareMining's alternative strategy that achieves the same goals through automated COBOL-to-Java translation.
Consider an example: identifying the logic used to calculate customer discounts. In a typical COBOL system, 500 lines of code may relate to discount calculation within a 5,000-line transaction program. Much of that code handles display, I/O, or validation rather than the core business rule itself.
Traditional BRE tools rely on heuristics to find relevant code, but they can miss key logic or include unnecessary details. As a result, organizations often need costly and time-consuming manual reviews to validate extracted rules.
Our experience shows that direct translation offers a more practical solution. Well-structured Java output from SoftwareMining's translator creates clear, self-documented code that reflects the original business logic while remaining easier to maintain and extend.
Large COBOL systems perform many tasks: generating reports, managing data-entry screens, printing, and implementing business rules such as eligibility or pricing. However, not all parts of these applications are suitable for rule-engine migration.
For most organizations, the best path is to first modernize the COBOL system into maintainable Java (or optionally C#). After this transformation, individual modules that truly represent business logic can be selectively refactored into a rule-based framework if desired.
Many documentation capabilities once associated with Business Rule Extraction are already available through modern development environments such as Eclipse IDE or Microsoft Visual Studio. Tools like "Find References" or "Call Hierarchy" make it easy to trace variable usage, understand program flow, and analyze dependencies.
SoftwareMining extends this capability by translating COBOL into well-structured Java (or optionally C#) code for documentation and analysis. The translated code can serve as a readable, navigable source reference without requiring runtime licenses. If the organization later decides to execute the translated system, runtime licenses can be added seamlessly.