Using OpenRewrite and JDT for transforming large applications By Ben Wilson

Does one of the projects you've got scheduled for your Java applications involve a lot of refactoring? In this session I will review two tools that can be used to refactor Java and some of the lessons learned from using them to facilitate big bang modernizations of applications with over 100 kLOC. As the average age of Java applications continues to rise, so does the popularity of frameworks like OpenRewrite that allow us to transform existing Java applications and refactor the sources consistently, without relying on hundreds or thousands of error-prone manual changes or requiring a deep understanding of what the code does. OpenRewrite and JDT are two reengineering tools with a significant user base but these tools come with a high learning curve. Not only is there the formality of the Java terminology that the developer needs to (re)master but both tools have their own APIs that map to the Java Language Specification in their own specific way. We will review the lessons learned from the experience of using both of these tools to modernize applications by performing a semi-automated migration of the frameworks they depend on, so that attendees can gain some insight to help make a choice based on their needs in future projects. BEN WILSON Ben Wilson is passionate about automated application modernization and has over 20 years' experience leading a broad set of its aspects ranging from R&D of transformation tooling products, to project management of modernization projects in Fortune 5000 companies. He is the Product Manager of Application Modernization at Vaadin, a company specializing in Web application and component frameworks for Java developers. Previously Ben was the Migration Practice Lead at Vaadin and was a director at Belgian Anubex where he was responsible for the big bang rollouts of several Tier 1 applications with over a million lines of code.