RestController for Byte Buddy instrumentation demo

HelloController.java

@RestController
public class HelloController {

    private static final String template = "Hello, %s!";

    @RequestMapping("/hello")
    public String greeting(
            @RequestParam(value = "name", defaultValue = "World") String name) {
        return String.format(template, name);
    }

    @RequestMapping("/browser")
    public String showUserAgent(HttpServletRequest request) {
        return request.getHeader("user-agent");
    }

}