Java—RequestMapping相关用法
RequestMapping是一个用来处理请求地址映射的注解,可用于类或方法上。用于类上,表示类中的所有响应请求的方法都是以该地址作为父路径。
它有6个属性:
1.value:指定请求的具体地址:
value的uri值为以下三类:
A) 可以指定为普通的具体值:
(value = "/add"),其直接访问controller的路径是ip:port/member/add。它还有一种写法就是下面例子中方法上的value = { "/add", "/add.html" },
它表示我们既可以通过:port/member/add来访问,也可以通过:port/member/add.html来访问。
@Controller @RequestMapping(value = "/member") public class MemberController extends BaseMultiController { @Autowired(required=true) private MemberService memberService; @RequestMapping(value = { "/add", "/add.html" }, method = { RequestMethod.GET,RequestMethod.POST }) @ResponseBody public ModelAndView add(HttpServletRequest request, HttpServletResponse response) { Map<String, Object> map = new HashMap<String, Object>(); Member member = new Member(); member.setId("1"); member.setNickname("guoxiaoming"); this.memberService.add(member); return toView("add", map); } }
B) 可以指定为含有某变量的一类值:也就是前台传来的参数,该参数day就是前台或者页面地址上带的参数;其写法是value="/{day}"
切记:必须在该参数的前面加上@PathVariable注解,这样才能表明该参数是变量
@RequestMapping(value="/{day}", method = RequestMethod.GET) public Map<String, Appointment> getForDay(@PathVariable @DateTimeFormat(iso=ISO.DATE) Date day, Model model) { return appointmentBook.getAppointmentsForDay(day); }
我们也可以将A和B两种结合起来使用,如下:value="/owners/{ownerId}
@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"; }
C) 可以指定为含正则表达式的一类值,如下value="/spring-web/{symbolicName:[a-z-]+}-{version:\d\.\d\.\d}.{extension:\.[a-z]}"。(不推荐使用)
@RequestMapping("/spring-web/{symbolicName:[a-z-]+}-{version:\d\.\d\.\d}.{extension:\.[a-z]}") public void handle(@PathVariable String version, @PathVariable String extension) { // ... }
2.method:指定请求的method类型, GET、POST、PUT、DELETE等;
通常我们只写method = RequestMethod.POST,测试时我们可以用method = RequestMethod.GET,还可以写成method = { RequestMethod.GET,RequestMethod.POST }
3.params: 指定request中必须包含某些参数值时才让该方法处理。
@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 } }
仅处理请求中包含了名为“myParam”,值为“myValue”的请求;
4.headers: 指定request中必须包含某些指定的header值,才能让该方法处理请求。
@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 } }
仅处理request的header中包含了指定“Refer”请求头和对应值为“http://www.ifeng.com/”的请求;
5.consumes: 指定处理请求的提交内容类型(Content-Type),例如application/json, text/html;
@Controller @RequestMapping(value = "/pets", method = RequestMethod.POST, consumes="application/json") public void addPet(@RequestBody Pet pet, Model model) { // implementation omitted }
方法仅处理request Content-Type为“application/json”类型的请求。
6.produces: 指定返回的内容类型,仅当request请求头中的(Accept)类型中包含该指定类型才返回;
@Controller @RequestMapping(value = "/pets/{petId}", method = RequestMethod.GET, produces="application/json") @ResponseBody public Pet getPet(@PathVariable String petId, Model model) { // implementation omitted }
方法仅处理request请求中Accept头中包含了"application/json"的请求,同时暗示了返回的内容类型为application/json。
这就是Java的魅力,你学会了吗?