JDecisiontable is a Java application to create decision tables. Explore all possible combinations of conditions and actions by question-and-answer, don't forget a combination conditions and actions, abandoned combinations are still documented, easy mathematics to find any incomplete or inconsistent decision table, and get a set of valid rules which are your test cases. Features include implements a proven and failsafe method, comprehensive checks, clear advice if a check failed, get test specifications from your decision table, allows working with probabilities, stores data not as binary or in database but in human-readable JSON text format, and comprehensive documentation about the application and the implemented method.