Seems my answer was a direct reply instead of the list…
Copy here:
Have a look at the Java cookbook attributes. There’s one for the job flavor and one for the version.
Make a wrapper cookbook overriding the Java attributes, depends on the tomcat cookbook and include the recipe.
You’ll have the correct jdk with tomcat.
Just to warn, installing oracle jdk on Ubuntu 12.04 override the system openjdk6 as the tomcat package depends on it (if you use the package way and not install from tarball)