springboot项目空值
springboot项目，前端页面部分数据为空，在输出台输出显示值为空。问应该如何完全查询数据，代码哪里写错了？
IDEA 2021.2.3 JDK17
代码部分：
控制器：
@Controller
@RequestMapping("/admin")
public class AdminController {
@Autowired
private AdminService adminService;
@RequestMapping("/to_login")
public String toLogin(){
return "admin/login";
}
@RequestMapping("/login")
public String login(Admin admin, HttpSession session, Model model){
if (!adminService.isValidatedUser(admin)){
model.addAttribute("login_error","登录失败！");
return "admin/login";
}
model.addAttribute("admin", admin);
System.out.println(admin);
session.setAttribute("login_name",admin.getLogin_name());
return "forward:/to_home_page?page=1&homePage=1";
}
mapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.javaee.dzy.mapper.AdminMapper">
<select id="findAdmins" resultType="Admin">
select * from admin
</select>
<select id="findAdminByUserId" parameterType="String" resultType="Admin">
select * from admin where user_id=#{user_id};
</select>
<select id="findAdminByLoginName" parameterType="String" resultType="Admin">
select * from admin where login_name=#{login_name};
</select>
<insert id="addAdmin" parameterType="Admin">
insert into admin(user_id,password,login_name,mobile) values(#{user_id},#{password},#{login_name},#{mobile});
</insert>
<delete id="deleteAdminByUserId" parameterType="String">
delete from admin where user_id=#{value};
</delete>
<update id="updateAdmin" parameterType="Admin">
update admin set login_name=#{login_name},mobile=#{mobile} where user_id=#{user_id};
</update>
<update id="resetPassword" parameterType="String">
update admin set password='123456' where user_id=#{value};
</update>
<update id="updatePassword" parameterType="Admin">
update admin set password=#{password} where login_name=#{loginName};
</update>
</mapper>
service
package com.javaee.dzy.Service.impl;
import com.javaee.dzy.Service.AdminService;
import com.javaee.dzy.mapper.AdminMapper;
import com.javaee.dzy.po.Admin;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import java.util.List;
@Service
@Transactional
public class AdminServiceImpl implements AdminService {
@Autowired
private AdminMapper adminMapper;
@Override
public boolean isValidatedUser(Admin admin) {
Admin dbAdmin = adminMapper.findAdminByUserId(admin.getUser_id());
if (dbAdmin == null)
return false;
if (dbAdmin.getPassword().equals(admin.getPassword()))
return true;
return false;
}
@Override
public List<Admin> findAdmins(){
return adminMapper.findAdmins();
}
@Override
public Admin findAdminByUserId(String user_id){
return adminMapper.findAdminByUserId(user_id);
}
@Override
public Admin findAdminByLoginName(String login_name){
return adminMapper.findAdminByLoginName(login_name);
}
@Override
public int addAdmin(Admin admin){
return adminMapper.addAdmin(admin);
}
@Override
public int deleteAdminByUserId(String user_id){
return adminMapper.deleteAdminByUserId(user_id);
}
@Override
public int updateAdmin(Admin admin){
return adminMapper.updateAdmin(admin);
}
@Override
public int updatePassword(String originPwd, String newPwd, String login_name) {
Admin admin = adminMapper.findAdminByLoginName(login_name);
if (originPwd.compareTo(admin.getPassword()) != 0)
return 0;
admin.setPassword(newPwd);
return adminMapper.updatePassword(admin);
}
@Override
public int resetPassword(String user_id) {
return adminMapper.resetPassword(user_id);
}
@Override
public boolean registerAdmin(Admin admin){
Admin dbAdmin = adminMapper.findAdminByLoginName(admin.getLogin_name());
if (dbAdmin != null)
return false;
int res = adminMapper.addAdmin(admin);
return res == 1;
}
}
html
```html
<div class='span12 box bordered-box green-border' style='margin-left:0px;'>
<div class='box-header sea-blue-background'>
<div class='title'>管理员信息列表</div>
</div>
<div class='box-content box-no-padding'>
<div class='responsive-table'>
<div class='scrollable-area'>
<table class='table table-bordered table-hover table-striped' style='margin-bottom:0;'>
<thead>
<tr><th>登录id</th><th>管理员登录名</th><th>电话</th><th>操作</th></tr>
</thead>
<tbody>
<tr id="${admin.user_id}" th:each="admin:${pageInfo.list}">
<td th:text="${admin.user_id}"></td>
<td th:text="${admin.login_name}"></td>
<td th:text="${admin.mobile}"></td>
<td width="150">
<div class='text-center'>
<a class='btn btn-success btn-mini' href='#' th:onclick="editAdmin([[${admin.user_id}]]);">编辑</a>
<a class='btn btn-danger btn-mini' href='#' th:onclick="deleteAdmin([[${admin.user_id}]]);">删除</a>
<a class='btn btn-warning btn-mini' href='#' th:onclick="resetPassword([[${admin.user_id}]]);">重置密码</a>
</div>
</td>
</tr>
</tbody>
</table>
</div>
</div>
</div>
<a th:href="@{/to_home_page(homePage=1,page=1)}">首页</a>
<a th:href="@{/to_home_page(homePage=1,page=${pageInfo.hasPreviousPage}?${pageInfo.prePage}:1)}">上一页</a>
<a th:href="@{/to_home_page(homePage=1,page=${pageInfo.hasNextPage}?${pageInfo.nextPage}:${pageInfo.pages})}">下一页</a>
<a th:href="@{/to_home_page(homePage=1,page=${pageInfo.pages})}">尾页</a>
当前 <span th:text="${pageInfo.pageNum}"></span> 页,总<span th:text="${pageInfo.pages}"></span> 页,共<span th:text="${pageInfo.total}"></span> 条记录<br/>
<a class='btn btn-success btn-small' data-toggle='modal' href='#modal-add-admin' role='button' onclick='addAdmin();'>添加</a>
</div>
TechWhizKid参考GPT回答：
可以考虑在验证用户之后更新你的admin对象，如下所示：
@RequestMapping("/login")
public String login(Admin admin, HttpSession session, Model model){
Admin dbAdmin = adminService.findAdminByUserId(admin.getUser_id());
if (dbAdmin == null || !dbAdmin.getPassword().equals(admin.getPassword())) {
model.addAttribute("login_error","登录失败！");
return "admin/login";
}
model.addAttribute("admin", dbAdmin);
System.out.println(dbAdmin);
session.setAttribute("login_name", dbAdmin.getLogin_name());
return "forward:/to_home_page?page=1&homePage=1";
}
修改后的方法中，首先从数据库获取Admin对象，然后检查密码是否匹配。如果验证成功，那么就将从数据库中检索到的dbAdmin对象返回给前端，而不是原始的、可能未完全填充的admin对象。这样，你应该可以在前端看到所有的管理员数据。
Admin中实体类的属性名定义错了，mybatis 默认开启了驼峰命名规则。
user_id 改为 userId
login_name 改为 loginName
看这个样子，你应该是开启了自动下划线转驼峰式命名了，看下你配置里是不是有这个配置mybatis.configuration.map-underscore-to-camel-case=true
你实体类字段都改成驼峰式的试试，user_id改成 userId，login_name改成loginName，注意页面里的也要一起修改。
能互相远程看一下吗兄弟，我这里有个问题也解决不了。。。
查看实体类Admin的各个属性和你的数据库admin表的各个字段保持一下一致
增删改查，别再自己写了
- 这篇博客也许可以解决你的问题👉 ：SpringBoot在普通类中调用service，mapper等
- 除此之外, 这篇博客: Springboot简单授权，限制访问中的 mapper.xml 部分也许能够解决你的问题, 你可以仔细阅读以下内容或跳转源博客中阅读:
<!--查询url--> <select id="selectUrl" resultType="com.thk.domain.Power"> SELECT p.url FROM rolemiddle as r LEFT JOIN power as p ON r.powerid=p.id WHERE r.roleid=#{id} </select><!--查询全部用户--> <select id="selectLists" resultType="com.thk.domain.People"> <include refid="selectPeopleVo"/> <where> <if test="name != null and name != ''">and name like concat('%', #{name}, '%')</if> <if test="age != null ">and age = #{age}</if> <if test="sex != null ">and sex = #{sex}</if> <if test="address != null and address != ''">and address = #{address}</if> <if test="userName != null and userName != ''">and user_name like concat('%', #{userName}, '%')</if> <if test="pwd != null and pwd != ''">and pwd = #{pwd}</if> <if test="email != null and email != ''">and email = #{email}</if> <if test="phonenumber != null and phonenumber != ''">and phonenumber = #{phonenumber}</if> <if test="loginIp != null and loginIp != ''">and login_ip = #{loginIp}</if> <if test="status != null and status != ''">and status = #{status}</if> <if test="loginDate != null ">and login_date = #{loginDate}</if> </where> </select>