Spring MVC Detailed explanation of how to process Ajax requests

import .*;
@RestController
@RequestMapping("/api")
public class MyController {
    @GetMapping("/data")
    public ResponseEntity<MyData> getData() {
        MyData data = new MyData(); // Create a data object        return (data); // Return data    }
    @PostMapping("/data")
    public ResponseEntity<String> postData(@RequestBody MyData data) {
        // Process the received data        return ("Data received successfully");
    }
}

<!--Must use it nowpostRequest method，becausegetNo request body-->
<form th:action="@{/test/RequestBody}" method="post">
    username：<input type="text" name="username"><br>
    password：<input type="password" name="password"><br>
    <input type="submit">
</form>

@RequestMapping("/test/RequestBody")
public String testRequestBody(@RequestBody String requestBody){
    ("requestBody:"+requestBody);
    return "success";
}

/* Method 1
 axios({
     method: 'get', // Request method, pass parameters in the form of name = value & name = value No matter whether the method of passing get or post, the request parameters will be spliced ​​to the request address.
           The request parameters in this way can be obtained through ()
     url: ‘', //Request path,
     params: {
        username: 'admin', //The request parameters sent in this json method are placed in the request body and transmitted to the server. The value transmitted in this way cannot be obtained by ()
        password: '123456'
        }
 }).then(function (response) {
       (response);
        = ;
     }
 */
/* request format of axios
  * Request method:
 * 1. ()
 * 2. ()
 * 3. ()
 * 4. ()
 * 5. ()
 * 6. ()
 * 7. ()
 * 8. ()
 //Method 2
   ("/test/RequestBody").then(function (response) {
       (response);
        = ;
       });
      },
 */
      /*
       * The format of the request body
       * 1. Pass parameters using url
       * 2. Pass parameters using json
       */

<dependency>
    <groupId></groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.1</version>
</dependency>

<!--OpenmvcAnnotation driver-->
<mvc:annotation-driven />

<input type="button" value="Test @RequestBody to get request parameters in json format"@click="testRequestBody()">
<script type="text/javascript" th:src="@{/js/}"></script>
<script type="text/javascript" th:src="@{/js/}"></script>
<script type="text/javascript">
    var vue = new Vue({
        el:"#app",
        methods:{
            testRequestBody(){
                (
                    "/SpringMVC/test/RequestBody/json",
                    {username:"admin",password:"123456"}
                ).then(response=>{
                    ();
                });
            }
        }
    });
</script>

//Convert json format data to map collection@RequestMapping("/test/RequestBody/json")
public void testRequestBody(@RequestBody Map<String, Object> map,HttpServletResponse response) throws IOException {
    (map);
    //{username=admin, password=123456}
    ().print("hello,axios");
}
//Convert json format data into entity class object@RequestMapping("/test/RequestBody/json")
public void testRequestBody(@RequestBody User user, HttpServletResponseresponse) throws IOException {
    (user);
    //User{id=null, username='admin', password='123456', age=null,gender='null'}
	().print("hello,axios");
}

@RequestMapping("/testResponseBody")
public String testResponseBody(){
    //At this time, it will jump to the page corresponding to the success of the logical view    return "success";
}
@RequestMapping("/testResponseBody")
@ResponseBody
public String testResponseBody(){
    //Respond to the browser data success at this time    return "success";
}

<dependency>
    <groupId></groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.12.1</version>
</dependency>

<!--OpenmvcAnnotation driver-->
<mvc:annotation-driven />

<input type="button" value="Test @ResponseBody to respond to data in browser json format"@click="testResponseBody()"><br>
<script type="text/javascript" th:src="@{/js/}"></script>
<script type="text/javascript" th:src="@{/js/}"></script>
<script type="text/javascript">
    var vue = new Vue({
        el:"#app",
        methods:{
            testResponseBody(){
                ("/SpringMVC/test/ResponseBody/json").then(response=>{
                    ();
                });
            }
        }
    });
</script>

//Respond to browser list collection@RequestMapping("/test/ResponseBody/json")
@ResponseBody
public List<User> testResponseBody(){
    User user1 = new User(1001,"admin1","123456",23,"male");
    User user2 = new User(1002,"admin2","123456",23,"male");
    User user3 = new User(1003,"admin3","123456",23,"male");
    List<User> list = (user1, user2, user3);
    return list;
}
//Response to the browser map collection@RequestMapping("/test/ResponseBody/json")
@ResponseBody
public Map<String, Object> testResponseBody(){
    User user1 = new User(1001,"admin1","123456",23,"male");
    User user2 = new User(1002,"admin2","123456",23,"male");
    User user3 = new User(1003,"admin3","123456",23,"male");
    Map<String, Object> map = new HashMap<>();
    ("1001", user1);
    ("1002", user2);
    ("1003", user3);
    return map;
}
//Respond to browser entity class object@RequestMapping("/test/ResponseBody/json")
@ResponseBody
public User testResponseBody(){
    return user;
}