Postman tests show the uri works. The goofy try/catch
is because I'm not sure how to mock the ServletContext in order
to unit test the HttpHeaders. This way at least it runs and
I can test the uri params (the important part anyway)

Constructor-based DI asserts that the class cannot
be instantiated without the supplied dependency. This method
enforces the requirement whether or not you use Spring, and
therefore is container-agnostic.

Also, Spring will throw up a Warning flag if you just annotate
the prop with @Inject

Mockito is lackluster, but i missed you, junit <3