I worked on a project to convert a city's billing and payment system for their water department from COBOL to JEE. It was actually pretty straight forward. The

I worked on a project to convert a city's billing and payment system for their water department from COBOL to JEE. It was actually pretty straight forward. The key to the project was being to easily convert the data in the mainframe to standard RDBMS tables, Oracle. After that it was just a matter of "mapping" the green screens of the system to web pages, i.e. displaying the same data and providing the same actions. The only time I really needed to grok any COBOL was when there were discrepancies between the old green screens and the new web pages. After a period of user testing it was basically do the final data dump to Oracle, turn on the new system and turn off the old one. However, there were many other programs running on the mainframe so the hardware didn't go anywhere.