SpringMvc接受請求參數的幾種情況演示

/**
     * 1.直接把表單的參數寫在Controller相應的方法的形參中
     *
     * @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、通過@PathVariable獲取路徑中的參數
     *
     * @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、通過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、通過一個bean來接收
     *
     * @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、用註解@RequestParam綁定請求參數到方法入參
     * @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;

/**
     *將json請求的key,value封裝到實體對象當中。
     * @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;
    }

/**
     * 將請求參數封裝到request對象當中。
     * @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;
    }

/**
     * 通過http協議將參數轉為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;
    }

//這裡使用的是alibaba的json工具類
    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());
        }
    }

/**
     *將json請求的Key,value封裝到map的key,value當中去。
     * @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;
    }