We are going to migrate our existing JavaEE project (with Vaadin 8 framework) to a Spring (non-boot) project and still keeping the current framework version. Having gone through the article “[Vaadin Spring Add-On]
(https://vaadin.com/docs/v8/framework/advanced/advanced-spring.html)”, one of the key challenges that we would face is of the urgency of updating our app via our Azure Cloud on a fortnightly basis in view of our clients visit the portal to analyze their data. However, we estimated that migrating this to using Spring Framework completely will take approximately 2-3 months. We are currently considering doing a gradual migration as I’ve seen this approach adopted by several organizations.
Some of our questions are:
- Apart from deploying base Spring UIs and servlets (I think this is definitely required), what would be the ideal way of doing a gradual migration while removing the dead / old code out?
- Does designating certain views with @SpringView annotation (e.g for non-critical) will cause functionality / integrity impacts to the application or all views have to be given the @SpringView in one develop/deployment iteration?
- Following #2, can a base view that is to be inherited by other views exempted from @SpringView annotation?
- Should we still keep the web.xml or restructure in a way that it is not needed as seen in the sample Bakery app?