:vim /shoe/ **/*.java will find all java files under the current directory, filter for ones containing the regex
/shoe/, and queue them all up to be edited.
:cw will open the list, letting you jump between all those files.
If you've ever run something like:
vim `grep -Rl shoe | grep .java`
...then Vim's internal grep is your friend.
:help :vim and
:help quickfix for more.