Revert "add db connection & select method"

This reverts commit b17d0bf6dd28086a20d75afa6063fcf2a94f8ea7.
Merge branch 'master' of github.com:jleefish/java3FinalProject
Merge branch 'master' of github.com:jleefish/java3FinalProject
Merge branch 'master' of github.com:jleefish/java3FinalProject

sd
finish controller(only refining left)