登录后保存用户信息到Session
login登录只要添加红色的2个地方

 HttpSession httpSession
 httpSession.setAttribute("username", username);
 httpSession.setAttribute("password", pwd);

Controller获取代码：（return JSON对象）

    @PostMapping("/getUserSession")
    public String getUserSession(HttpServletRequest request, HttpSession httpSession) {
        JSONObject jsonObject = new JSONObject();
        if(httpSession!=null){
            jsonObject.put("usernameaa", httpSession.getAttribute("username"));
//            jsonObject.put("password", httpSession.getAttribute("password"));
        }
        return JSONObject.toJSONString(jsonObject);
    }

再在前端js中调用Controller第二个方法，获取session内容
JS中代码：

$.ajax({
            url: '/user/getUserSession',
            dataType:'json',
            type: 'post',
            success: function (data) { 
                alert("usernameaa"+data.usernameaa);
            }
        });

第二种方法


common.js

/**
 * 接受url传的id
 * @param name
 * @returns {string}
 */
function getQueryString(name) {
    var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)");
    var r = window.location.search.substr(1).match(reg);
    if (r != null) {
        return decodeURIComponent(r[2]);
    }
    return '';
}