RequestMapping（映射请求）:Ant风格;Rest风格;限定请求方法;限定参数;限定请求头信息
标准URL映射
@RequestMapping(value=”xxx”)
在springmvc众多Controller以及每个Controller的众多方法中，请求时如何映射到具体的处理方法上
它可以定义在方法上，也可以定义在类上
请求映射的规则：
类上的@RequestMapping的value+方法上的@RequestMapping的value，如果value不以“/”开头，springmvc会自动加上 类上的@RequestMapping可省略，这时请求路径就是方法上的@RequestMapping的value
@RequestMapping("hello")
@Controller
public class Hello2Controller {
@RequestMapping("show1")
public ModelAndView test1(){
ModelAndView mv = new ModelAndView();
mv.setViewName("hello");
mv.addObject("msg", "这是SpringMVC的第一个注解程序！");
return mv;
}
}
Ant风格的映射
- ?：通配一个字符
- *：通配0个或者多个字符
-
**：通配0个或者多个路径
@RequestMapping(“aa?/show2”) public ModelAndView test2(){ ModelAndView mv = new ModelAndView(); mv.setViewName(“hello”); mv.addObject(“msg”, “ant风格的映射：？”); return mv; }
@RequestMapping(“bb/show3”) public ModelAndView test3(){ ModelAndView mv = new ModelAndView(); mv.setViewName(“hello”); mv.addObject(“msg”, “ant风格的映射：”); return mv; }
@RequestMapping(“/show4”) public ModelAndView test4(){ ModelAndView mv = new ModelAndView(); mv.setViewName(“hello”); mv.addObject(“msg”, “ant风格的映射：”); return mv; }
Rest风格的映射（占位符的映射）
@RequestMapping(value=“/user/{userId}/{name} “)
请求URL：http://localhost:8080/user/1001/zhangsan.do
这种方式虽然和通配符“*”类似，却比通配符更加强大，占位符除了可以起到通配的作用，最精要的地方是在于它还可以传递参数。
比如：通过@PathVariable(“userId”) Long id, @PathVariable(“name”)String name获取对应的参数。
注意：@PathVariable(“key”)中的key必须和对应的占位符中的参数名一致，而方法形参的参数名可任意取
@RequestMapping("show5/{name}/{id}")
public ModelAndView test5(@PathVariable("name")String name, @PathVariable("id")Long id){
ModelAndView mv = new ModelAndView();
mv.setViewName("hello");
mv.addObject("msg", "rest风格的映射：name=" + name + ",id=" + id);
return mv;
}
如果传递的参数类型和接受参数的形参类型不一致，则会自动转换，如果转换出错（例如：id传了abc字符串，方法形参使用Long来接受参数），则会报400错误（参数列表错误）。
限定请求方法的映射
@RequestMapping(value=””, method=RequestMethod.POST)
@RequestMapping(value = "show6", method = RequestMethod.POST)
public ModelAndView test6(){
ModelAndView mv = new ModelAndView();
mv.setViewName("hello");
mv.addObject("msg", "限定请求方法的映射：POST");
return mv;
}
用到了框架提供的RequestMethod枚举类，源代码截图：
此时show6限定请求方法为POST请求，如果通过浏览器地址栏输入请求路径（也就是GET请求），结果：
输入：http://localhost:8080/springmvc01/show6.do
限定多种请求方法
@RequestMapping(value=””, method={RequestMethod.POST, RequestMethod.GET})
@RequestMapping(value = "show7", method = {RequestMethod.POST, RequestMethod.GET})
public ModelAndView test7(){
ModelAndView mv = new ModelAndView();
mv.setViewName("hello");
mv.addObject("msg", "限定请求方法的映射：POST");
return mv;
}
限定参数的映射
@RequestMapping(value=””,params=””)
params=”userId”：请求参数中必须带有userId
params=”!userId”：请求参数中不能包含userId
params=”userId=1”：请求参数中userId必须为1
params=”userId!=1”：请求参数中userId必须不为1，参数中可以不包含userId
params={“userId”, ”name”}：请求参数中必须有userId，name参数
@RequestMapping(value = "show8", params = "id")
public ModelAndView test8() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "springmvc的映射之限定请求参数，id");
return mv;
}
@RequestMapping(value = "show9", params = "!id")
public ModelAndView test9() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "springmvc的映射之限定请求参数，!id");
return mv;
}
@RequestMapping(value = "show10", params = "id=1")
public ModelAndView test10() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "springmvc的映射之限定请求参数，id=1");
return mv;
}
@RequestMapping(value = "show11", params = "id!=1")
public ModelAndView test11() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "springmvc的映射之限定请求参数，id!=1");
return mv;
}
@RequestMapping(value = "show12", params = { "id", "name" })
public ModelAndView test12() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "springmvc的映射之限定请求参数，id,name");
return mv;
}
http://localhost:8080/springmvc01/show9.do?id=wjw
http://localhost:8080/springmvc01/show8.do?id=wjw
限定请求头信息的映射
@RequestMapping(value=””, heads=””)
/**
* 1.请求头信息必须包含User-Agent
* 2.User-Agent头参数的值必须为Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36
* 即：限定浏览器必须是谷歌浏览器，而且版本还是Chrome/69.0.3497.100
* @return
*/
@RequestMapping(value = "show13", headers = "User-Agent=Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36")
public ModelAndView test13() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "限定请求头信息");
return mv;
}
火狐浏览器测试：
组合注解
GetMapping：相当于RequestMapping（method = RequestMethod.GET）
PostMapping：相当于RequestMapping（method = RequestMethod.POST）
PutMapping：相当于RequestMapping（method = RequestMethod.PUT）
DeleteMapping：相当于RequestMapping（method = RequestMethod.DELETE）
@GetMapping(value = "show14")
public ModelAndView test14() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "GetMapping");
return mv;
}
@PostMapping(value = "show15")
public ModelAndView test15() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "PostMapping");
return mv;
}
@PutMapping(value = "show16")
public ModelAndView test16() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "PutMapping");
return mv;
}
@DeleteMapping(value = "show17")
public ModelAndView test17() {
ModelAndView mv = new ModelAndView("hello");
mv.addObject("msg", "DeleteMapping");
return mv;
}
