Research On Symbol System In The Process Of Automatic Transformation From COBOL Legacy System To Java Platform

COBOL was designed for data process and therefore is mostly used in the business area. As time goes on, all kinds of modern programming languages are invented. COBOL is gradually abandoned by engineers. However, a huge amount of COBOL systems are still running core business for a lot of companies. It costs them great expense to maintain these legacy systems. Currently, there’s no satisfactory solution that transforms a COBOL system into a system that runs in a modern language environment.There are two basic problems in the automatic transformation of COBOL systems to Java environment:data definition and reference, paragraph definition and reference. This paper puts forward a "fields mapping" solution based on storage encapsulation mechanism. Using this solution, readability and performance of the target system are highly improved; the copy book problem is also solved, leading to a very low code expansion rate. We also present a new control flow refactoring algorithm, which successfully transforms COBOL goto and perform statements into Java method. Based on this algorithm, a few optimization methods are used for further program structuring. Comparing with other solutions, readability and modularity of the target system are greatly enhanced.