Tomcat 10 renamed every import in your application
Tomcat 8.5 is past end of life and Tomcat 9 follows. Tomcat 10 moved to the Jakarta namespace, so the upgrade changes every servlet import in the deployed application, not just the container.
Challenge
Tomcat 9 to 10 is a namespace migration, not a container upgrade. Every javax.servlet import in the application and its dependencies becomes jakarta.servlet -- which means the applications deployed on it have to change, not just the server they run on.
Environment
Apache Tomcat 8.5 or 9 serving production Java applications built against the javax servlet namespace.
Approach
OSSeva patches the running Tomcat line so the container is covered while the Jakarta migration is scoped against the deployed applications and their dependency trees.
What this delivers
A patched container today, and a Tomcat 10 move planned against the application estate that actually has to change.