I'm a freelance full stack developer and have seen lots of different enterprise systems go from bleeding edge to legacy. Nevertheless they prove their success by withstanding the requirements of everyday life and do just work. To ensure they will continue to do exactly that in the future, I can help you to adapt them to continuously changing requirements and business cases.
If you have a Java enterprise system like this or want to develop a new one or need some training on the latest tools, I am here to help. I'll be happy to hear from you.