Spring MVC之@RequestMapping 詳解 Spring MVC之@RequestMapping 詳解
轉自原文 Spring MVC之@RequestMapping 詳解
引言:
前段時間專案中用到了REST風格來開發程式,但是當用POST、PUT模式提交資料時,發現伺服器端接受不到提交的資料(伺服器端引數繫結沒有加 任何註解),查看了提交方式為application/json, 而且伺服器端通過request.getReader() 打出的資料裡確實存在瀏覽器提交的資料。為了找出原因,便對引數繫結(@RequestParam、 @RequestBody、 @RequestHeader 、 @PathVariable)進行了研究,同時也看了一下HttpMessageConverter的相關內容,在此一併總結。
簡介:
@RequestMapping
RequestMapping是一個用來處理請求地址對映的註解,可用於類或方法上。用於類上,表示類中的所有響應請求的方法都是以該地址作為父路徑。
RequestMapping註解有六個屬性,下面我們把她分成三類進行說明。
1、 value, method;
value: 指定請求的實際地址,指定的地址可以是URI Template 模式(後面將會說明);
method: 指定請求的method型別, GET、POST、PUT、DELETE等;
2、 consumes,produces;
consumes: 指定處理請求的提交內容型別(Content-Type),例如application/json, text/html;
produces: 指定返回的內容型別,僅當request請求頭中的(Accept)型別中包含該指定型別才返回;
3、 params,headers;
params: 指定request中必須包含某些引數值是,才讓該方法處理。
headers: 指定request中必須包含某些指定的header值,才能讓該方法處理請求。
示例:
1、value / method 示例
預設RequestMapping("....str...")即為value的值;
- @Controller
- @RequestMapping("/appointments")
- public class AppointmentsController {
- private final AppointmentBook appointmentBook;
- @Autowired
- public AppointmentsController(AppointmentBook appointmentBook) {
- this.appointmentBook = appointmentBook;
- }
- @RequestMapping(method = RequestMethod.GET)
- public Map<String, Appointment> get() {
- return appointmentBook.getAppointmentsForToday();
- }
- @RequestMapping(value="/{day}", method = RequestMethod.GET)
- public Map<String, Appointment> getForDay(@PathVariable @DateTimeFormat(iso=ISO.DATE) Date day, Model model) {
- return appointmentBook.getAppointmentsForDay(day);
- }
- @RequestMapping(value="/new", method = RequestMethod.GET)
- public AppointmentForm getNewForm() {
- return new AppointmentForm();
- }
- @RequestMapping(method = RequestMethod.POST)
- public String add(@Valid AppointmentForm appointment, BindingResult result) {
- if (result.hasErrors()) {
- return "appointments/new";
- }
- appointmentBook.addAppointment(appointment);
- return "redirect:/appointments";
- }
- }
value的uri值為以下三類:
A) 可以指定為普通的具體值;
B) 可以指定為含有某變數的一類值(URI Template Patterns with Path Variables);
C) 可以指定為含正則表示式的一類值( URI Template Patterns with Regular Expressions);
example B)
- @RequestMapping(value="/owners/{ownerId}", method=RequestMethod.GET)
- public String findOwner(@PathVariable String ownerId, Model model) {
- Owner owner = ownerService.findOwner(ownerId);
- model.addAttribute("owner", owner);
- return "displayOwner";
- }
example C)
- @RequestMapping("/spring-web/{symbolicName:[a-z-]+}-{version:\d\.\d\.\d}.{extension:\.[a-z]}")
- public void handle(@PathVariable String version, @PathVariable String extension) {
- // ...
- }
- }
2 consumes、produces 示例
cousumes的樣例:
- @Controller
- @RequestMapping(value = "/pets", method = RequestMethod.POST, consumes="application/json")
- public void addPet(@RequestBody Pet pet, Model model) {
- // implementation omitted
- }
方法僅處理request Content-Type為“application/json”型別的請求。
produces的樣例:
- @Controller
- @RequestMapping(value = "/pets/{petId}", method = RequestMethod.GET, produces="application/json")
- @ResponseBody
- public Pet getPet(@PathVariable String petId, Model model) {
- // implementation omitted
- }
方法僅處理request請求中Accept頭中包含了"application/json"的請求,同時暗示了返回的內容型別為application/json;
3 params、headers 示例
params的樣例:
- @Controller
- @RequestMapping("/owners/{ownerId}")
- public class RelativePathUriTemplateController {
- @RequestMapping(value = "/pets/{petId}", method = RequestMethod.GET, params="myParam=myValue")
- public void findPet(@PathVariable String ownerId, @PathVariable String petId, Model model) {
- // implementation omitted
- }
- }
僅處理請求中包含了名為“myParam”,值為“myValue”的請求;
headers的樣例:
- @Controller
- @RequestMapping("/owners/{ownerId}")
- public class RelativePathUriTemplateController {
- @RequestMapping(value = "/pets", method = RequestMethod.GET, headers="Referer=http://www.ifeng.com/")
- public void findPet(@PathVariable String ownerId, @PathVariable String petId, Model model) {
- // implementation omitted
- }
- }
僅處理request的header中包含了指定“Refer”請求頭和對應值為“http://www.ifeng.com/
”的請求。