SpringMVC=>Ajax

@ page contentType="text/html;charset=UTF-8" language="java" %>
html>
head>
    title>Titletitle>
    script src="statics/js/jquery-3.5.1.js">script>
    script>
        function a1() {

        $.post({
            url: "${pageContext.request.contextPath}/a3",
            data:{"name":$("#name").val()},
            success:function (data) {  //callback 回调函数
                if (data.toString()===‘ok‘){
                    $("#userInfo").css("color","green");
                }else{
                    $("#userInfo").css("color","red");
                }
                $("#userInfo").html(data);
            }
        });
        }

        function a2() {
            $.post({
                url: "${pageContext.request.contextPath}/a3",
                data:{"pwd":$("#pwd").val()},
                success:function (data) {  //callback 回调函数
                    if (data.toString()===‘ok‘){
                        $("#pwdInfo").css("color","green");
                    }else{
                        $("#pwdInfo").css("color","red");
                    }
                    $("#pwdInfo").html(data);
                }
            });
        }
    script>
head>
body>
p>
    用户名: input type="text" id="name" onblur="a1()">
    span id="userInfo">span>
p>
p>
    密码: input type="text" id="pwd" onblur="a2()">
    span id="pwdInfo">span>
p>
body>
html>

package com.min.controller;

import com.min.pojp.User;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

@RestController //加上这个会自动返回字符串
public class AjaxController {

    @RequestMapping("/t1")
    public String test() {
        return "hello";
    }


    @RequestMapping("/a1")
    public void a1(String name, HttpServletResponse response) throws IOException {
        System.err.println("a1:param=>" + name);
        if ("666".equals(name)) {
            response.getWriter().print("true");
        } else {
            response.getWriter().print("false");
        }
    }

    @RequestMapping("/a2")
    public List a2() { //接收 添加数据 返回数据
        List userList = new ArrayList();
        userList.add(new User("张三", 18, "男"));
        userList.add(new User("李四", 22, "男"));
        userList.add(new User("王五", 16, "男"));
        return userList;
    }

    @RequestMapping("/a3")
    public String a3(String name, String pwd) {
        String msg = "";
        if (name != null) {
            if ("admin".equals(name)) {
                msg = "ok";
            }else{
                msg = "用户名有误！";
            }
        }
        if (pwd != null) {
            if ("123456".equals(pwd)) {
                msg = "ok";
            }else{
                msg = "密码有误！";
            }
        }
        return msg;
    }

}