To use logback access with Spring Boot and its embedded Tomcat I find myself having to set up the LogbackValve programmatically.

My app's configuration is packaged as a resource inside the application jar, however ch.qos.logback.access.tomcat.LogbackValve has only a setFilename method that requires a path to a normal java.io.File.

I propose to refactor the class and add the possibility to read from classpath resources as well. In alternative moving the configuration reading operation to a dedicated method that a subclass can override would be enough.
The second approach should be trivial and I could provide a patch if desired.