A Cobol to Java transpiler.
Companies have large legacy code bases which are hard to migrate manually. The Amazing Cobol To Java Transpiler is meant to explore one possible solution: automatic source code transpilation. Right now this project is work in progress, focusing on COBOL85 code bases only.
Install a Java SE Development Kit as well as Apache Maven. Clone or download this repository, and build by running:
$ mvn installTo transpile a single file of COBOL code run:
$ java -jar actojat-cli/target/actojat.jar /path/to/test-source-helloworld.cob TestName2 my.base.pckg COBOL /tmp/ falseActojat is still work in progress. The following table provides you with an overview, which language features of the COBOL85 language standard are already supported:
| Feature (Keyword) | Description | Implemented? | Sample COBOL code | Generated Java Code |
|---|---|---|---|---|
| Conditional operators | Greater, lesser, ... | yes | conditional.cob | IfThenElseAndConditions.java |
| IF .. THEN ... ELSE | Common branching | yes | conditional.cob | IfThenElseAndConditions.java |
| PERFORM ... TIMES | For-loops | yes | performtimes.cob | PerformTimes.java |
| PERFORM ... UNTIL | While-loops | yes | performuntil.cob | PerformUntil.java |
| PERFORM ... VARYING | Multi-var. For-loops | no | ... | ... |
| PICTURE | Variable declaration | yes (partially) | ... | ... |
| MOVE | Assignment | no | ... | ... |
| ... | ... | no | ... | ... |
Actojat uses ANTLR for some of the heavy lifting: at the transpiler's heart lies a grammar file that describes the COBOL85 standard in an ANTLR-specific dialect of common BNF, ANTLR's Maven plugin is used to generate parser and tokenizer classes.
With these parser and tokenizer classes an AST for a given COBOL source file is then created. The CobolVisitor then creates an intermediate representation of the corresponding Java program from which the actual Java code is generated.
A module that implements support for ANSI C transpilation was added only to guarantee that the transpiler infrastructure has at least some degree of generality.