table of Contents
Common parameter annotation use
annotation:
@PathVariable 路径变量
@RequestHeader 获取请求头
@RequestParam 获取请求参数（指问号后的参数，url?a=1&b=2）
@CookieValue 获取Cookie值
@RequestAttribute 获取request域属性
@RequestBody 获取请求体[POST]
@MatrixVariable 矩阵变量
@ModelAttribute
Use case:
@RestController
public class ParameterTestController {
// car/2/owner/zhangsan
@GetMapping("/car/{id}/owner/{username}")
public Map<String,Object> getCar(@PathVariable("id") Integer id,
@PathVariable("username") String name,
@PathVariable Map<String,String> pv,
@RequestHeader("User-Agent") String userAgent,
@RequestHeader Map<String,String> header,
@RequestParam("age") Integer age,
@RequestParam("inters") List<String> inters,
@RequestParam Map<String,String> params,
@CookieValue("_ga") String _ga,
@CookieValue("_ga") Cookie cookie){
Map<String,Object> map = new HashMap<>();
// map.put("id",id);
// map.put("name",name);
// map.put("pv",pv);
// map.put("userAgent",userAgent);
// map.put("headers",header);
map.put("age",age);
map.put("inters",inters);
map.put("params",params);
map.put("_ga",_ga);
System.out.println(cookie.getName()+"===>"+cookie.getValue());
return map;
}
@PostMapping("/save")
public Map postMethod(@RequestBody String content){
Map<String,Object> map = new HashMap<>();
map.put("content",content);
return map;
}
}
@RequestAttribute
@Controller
public class RequestController {
@GetMapping("/goto")
public String goToPage(HttpServletRequest request){
request.setAttribute("msg","成功了...");
request.setAttribute("code",200);
return "forward:/success"; //转发到 /success请求
}
@GetMapping("/params")
public String testParam(Map<String,Object> map,
Model model,
HttpServletRequest request,
HttpServletResponse response){
map.put("hello","world666");
model.addAttribute("world","hello666");
request.setAttribute("message","HelloWorld");
Cookie cookie = new Cookie("c1","v1");
response.addCookie(cookie);
return "forward:/success";
}
///<-----------------主角@RequestAttribute在这个方法
@ResponseBody
@GetMapping("/success")
public Map success(@RequestAttribute(value = "msg",required = false) String msg,
@RequestAttribute(value = "code",required = false)Integer code,
HttpServletRequest request){
Object msg1 = request.getAttribute("msg");
Map<String,Object> map = new HashMap<>();
Object hello = request.getAttribute("hello");
Object world = request.getAttribute("world");
Object message = request.getAttribute("message");
map.put("reqMethod_msg",msg1);
map.put("annotation_msg",msg);
map.put("hello",hello);
map.put("world",world);
map.put("message",message);
return map;
}
}
@MatrixVariable与UrlPathHelper
Syntax: Request path: /cars/sell;low=34;brand=byd,audi,yd
SpringBoot disables the function of matrix variables by default
Manual opening: principle. The processing of the path. The removeSemicolonContent of UrlPathHelper is set to false to allow it to support matrix variables.
Matrix variables must have URL path variables to be parsed
Manually open matrix variables:
Implement the WebMvcConfigurer interface:
@Configuration(proxyBeanMethods = false)
public class WebConfig implements WebMvcConfigurer {
@Override
public void configurePathMatch(PathMatchConfigurer configurer) {
UrlPathHelper urlPathHelper = new UrlPathHelper();
// 不移除；后面的内容。矩阵变量功能就可以生效
urlPathHelper.setRemoveSemicolonContent(false);
configurer.setUrlPathHelper(urlPathHelper);
}
}
Create and return WebMvcConfigurerBean:
@Configuration(proxyBeanMethods = false)
public class WebConfig{
@Bean
public WebMvcConfigurer webMvcConfigurer(){
return new WebMvcConfigurer() {
@Override
public void configurePathMatch(PathMatchConfigurer configurer) {
UrlPathHelper urlPathHelper = new UrlPathHelper();
// 不移除；后面的内容。矩阵变量功能就可以生效
urlPathHelper.setRemoveSemicolonContent(false);
configurer.setUrlPathHelper(urlPathHelper);
}
}
}
}
@MatrixVariable example
@RestController
public class ParameterTestController {
///cars/sell;low=34;brand=byd,audi,yd
@GetMapping("/cars/{path}")
public Map carsSell(@MatrixVariable("low") Integer low,
@MatrixVariable("brand") List<String> brand,
@PathVariable("path") String path){
Map<String,Object> map = new HashMap<>();
map.put("low",low);
map.put("brand",brand);
map.put("path",path);
return map;
}
// /boss/1;age=20/2;age=10
@GetMapping("/boss/{bossId}/{empId}")
public Map boss(@MatrixVariable(value = "age",pathVar = "bossId") Integer bossAge,
@MatrixVariable(value = "age",pathVar = "empId") Integer empAge){
Map<String,Object> map = new HashMap<>();
map.put("bossAge",bossAge);
map.put("empAge",empAge);
return map;
}
}