Much of the software in the world today was developed from the mid-1960s to the mid- 1970s.This legacy software deteriorates as it is modified to satisfy new organizational requirements. Currently, legacy system maintenance requires more time than new system development. Eventually, legacy systems must be replaced. Identifying their functionality is a critical part of the replacement effort. Recovering functions from source code is difficult because the domain knowledge used to develop the system is not routinely retained. The source code is frequently the only reliable source of functional information.
This dissertation describes functional process information recovery from COBOL source code in the military logistics system domain. The methodology was developed as an information processing application. Conceptual and logical models to convert source code to functional design information were created to define the process. A supporting data structure was also developed.
The process reverse engineering methodology was manually applied to a test case to demonstrate feasibility, practicality, and usefulness. Metrics for predicting the time required were developed and analyzed based on the results of the test case.
The methodology was found to be effective in recovering functional process information from source code. A prototype program information database was developed and implemented to aid in data collection and manipulation; it also supported the process of preparing program structure models. Recommendations for further research include applying the methodology. to a larger test case to validate findings and extending it to include a comparable data reverse engineering procedure
