SpringMvc接受请求参数的几种情况演示

/**

      * 1.直接把表单的参数写在Controller相应的方法的形参中

      *

      * @param username

      * @param password

      * @return

      */

     @GetMapping ( "/addUser1" )

     public String addUser1(String username, String password) {

         System.out.println ( "username is:" + username);

         System.out.println ( "password is:" + password);

         return username + "," + password;

     }

/**

      * 2、通过@PathVariable获取路径中的参数

      *

      * @param username

      * @param password

      * @return

      */

     @RequestMapping (value = "/addUser4/{username}/{password}" , method = RequestMethod.GET)

     public String addUser4( @PathVariable String username, @PathVariable String password) {

         System.out.println ( "username is:" + username);

         System.out.println ( "password is:" + password);

         return "addUser4" ;

     }

/**

      * 3、通过HttpServletRequest接收

      *

      * @param request

      * @return

      */

     @RequestMapping ( "/addUser2" )

     public String addUser2(HttpServletRequest request) {

         String username = request.getParameter ( "username" );

         String password = request.getParameter ( "password" );

         System.out.println ( "username is:" + username);

         System.out.println ( "password is:" + password);

         return "demo/index" ;

     }

package com.example.demo.pojo;

import lombok.Data;

@Data

public class User1 {

     private String username;

     private String password;

}

/**

      * 4、通过一个bean来接收

      *

      * @param user

      * @return

      */

     @RequestMapping ( "/addUser3" )

     public String addUser3(User1 user) {

         System.out.println ( "username is:" + user.getUsername ( ));

         System.out.println ( "password is:" + user.getPassword ( ));

         return "/addUser3" ;

     }

/**

      * 5、用注解@RequestParam绑定请求参数到方法入参

      * @param username

      * @param password

      * @return

      */

     @RequestMapping (value= "/addUser6" ,method=RequestMethod.GET)

     public String addUser6( @RequestParam ( "username" ) String username, @RequestParam ( "password" ) String password) {

         System.out.println( "username is:" +username);

         System.out.println( "password is:" +password);

         return "demo/index" ;

     }

public class User2 implements Serializable {

     private static final long serialVersionUID = 1L;

     @JsonProperty (value = "id" )

     private Integer id;

     @JsonProperty (value = "name" )

     private String name;

     @JsonProperty (value = "age" )

     private Integer age;

     @JsonProperty (value = "hobby" )

     private List<String> hobby;

/**

      *将json请求的key,value封装到实体对象当中。

      * @param user

      * @return

      */

     @PostMapping ( "/save" )

     public String saveUser( @RequestBody User2 user) {

//        list.add(user);

//        User2 user2 = new User2 (  );

//        user2.setId (user.getId ());

//        user2.setAge (user.getAge ());

//        user2.setName (user.getName ());

//        user2.setHobby (user.getHobby ());

         return "success" +user;

     }

/**

      * 将请求参数封装到request对象当中。

      * @param request

      * @return

      */

     @PostMapping ( "/save2" )

     public User2 save(HttpServletRequest request) {

         Integer id = Integer.parseInt(request.getParameter( "id" ));

         String name = request.getParameter( "name" );

         Integer age = Integer.parseInt(request.getParameter( "age" ));

         String parameter = request.getParameter( "hobby" );

         List<String> stringList = new ArrayList<> (  );

         String[] split = parameter.split ( "," );

         for ( int i = split.length - 1 ; i >= 0 ; i--) {

             stringList.add (split[i]);

         }

         User2 user2 = new User2(id, name, age, stringList);

//        list.add(user);

         return user2;

     }

/**

      * 通过http协议将参数转为jsonobject

      * @param request

      * @return

      * @throws IOException

      * @throws JSONException

      */

     @PostMapping ( "/save3" )

     public User2 save3(HttpServletRequest request) throws IOException, JSONException {

         JSONObject jsonObject = handlerData(request);

         Integer id = jsonObject.getInteger( "id" );

         String name = jsonObject.getString( "name" );

         Integer age = jsonObject.getInteger( "age" );

         List<String> hobby = jsonObject.getObject( "hobby" , List. class );

         User2 user3 = new User2 (id, name, age, hobby);

//        list.add(user);

         return user3;

     }

//这里使用的是alibaba的json工具类

     public static JSONObject handlerData(HttpServletRequest request) throws IOException, JSONException {

         StringBuffer sb = new StringBuffer();

         InputStream is = request.getInputStream();

         BufferedReader br = new BufferedReader( new InputStreamReader (is, "utf-8" ));

         String s = "" ;

         while ((s = br.readLine()) != null ) {

             sb.append(s);

         }

         if (sb.toString().length() <= 0 ) {

             return null ;

         } else {

             return JSONObject.parseObject(sb.toString());

         }

     }

/**

      *将json请求的Key,value封装到map的key,value当中去。

      * @param map

      * @return

      */

     @PostMapping ( "/save1" )

     public User2 saveUser1( @RequestBody Map<String, Object> map) {

         Integer id = (Integer) map.get( "id" );

         String name = (String) map.get( "name" );

         Integer age = (Integer) map.get( "age" );

         List<String> hobby=(List<String>) map.get( "hobby" );

         User2 user = new User2(id, name, age, hobby);

//        list.add(user);

         return user;

     }