[springmvc]Generating responses

1. Return a POJO annotated with @ResponseBody: POJO marshaled as the body of the response

    @RequestMapping(value="/response/annotation", method=RequestMethod.GET)
    public @ResponseBody String responseBody() {
        return "The String ResponseBody";
    }

    @RequestMapping(value="/response/charset/accept", method=RequestMethod.GET)
    public @ResponseBody String responseAcceptHeaderCharset() {
        return "こんにちは世界！ (\"Hello world!\" in Japanese)";
    }

    @RequestMapping(value="/response/charset/produce", method=RequestMethod.GET, produces="text/plain;charset=UTF-8")
    public @ResponseBody String responseProducesConditionCharset() {
        return "こんにちは世界！ (\"Hello world!\" in Japanese)";
    }

2. Return a new ResponseEntity<T> object

    @RequestMapping(value="/response/entity/status", method=RequestMethod.GET)
    public ResponseEntity<String> responseEntityStatusCode() {
        return new ResponseEntity<String>("The String ResponseBody with custom status code (403 Forbidden)",
                HttpStatus.FORBIDDEN);
    }

    @RequestMapping(value="/response/entity/headers", method=RequestMethod.GET)
    public ResponseEntity<String> responseEntityCustomHeaders() {
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.TEXT_PLAIN);
        return new ResponseEntity<String>("The String ResponseBody with custom header Content-Type=text/plain",
                headers, HttpStatus.OK);
    }