Prior to this commit, handler methods in Spring MVC controllers were
not required to provide explicit path mappings via @RequestMapping (or
any of its specializations such as @GetMapping). Such handler methods
were effectively mapped to all paths. Consequently, developers may have
unwittingly mapped all requests to a single handler method.
This commit addresses this by enforcing that @RequestMapping methods
are mapped to an explicit path. Note, however, that this is enforced
after type-level and method-level @RequestMapping information has been
merged.
Developers wishing to map to all paths should now add an explicit path
mapping to "/**" or "**".
Closes gh-22543