查不到数据，值为null,怀疑是数据库没连接上，用的是mysql8.0.17的
driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/mydb?useSSL=false&serverTimezone=UTC
username=root
password=root
package com.imooc.entity;
import java.util.Date;
import java.util.List;
/**
* Created by mouwe on 2017/5/17.
* resource:mybatis-config.xml
* InputStream
* SqlSessionFactory
* SqlSession
* 执行我们的配置好的SQL语句
*/
public class Users {
private Integer id; // 用户编号
// private String username; // 登录账号
private String name; // 登录账号
private String userpass; // 登录密码
private String nickname; // 用户昵称
private Integer age; // 用户年龄
private String gender; // 用户性别
private String email; // 用户邮箱
private String phone; // 联系方式
private Date createTime; // 创建时间
private Date updateTime; // 账号最后修改时间
private Date lastLogin; // 用户最后登录时间
private Integer userStatus; // 用户账号状态 0 正常 1 锁定 2 删除
private String remark; // 用户备注信息
private List<Address> addresses; // 用户地址信息【地址列表，有一个是默认地址】
public Users() {
}
public Users(Integer id) {
this.id = id;
}
public Users(String name, String userpass, String nickname, Integer age, String gender, String email, String phone) {
this.name = name;
this.userpass = userpass;
this.nickname = nickname;
this.age = age;
this.gender = gender;
this.email = email;
this.phone = phone;
}
public Users(Integer id, String nickname, Integer age, String gender, String email, String phone, Date updateTime, String remark) {
this.id = id;
this.nickname = nickname;
this.age = age;
this.gender = gender;
this.email = email;
this.phone = phone;
this.updateTime = updateTime;
this.remark = remark;
}
public Users(String name, String userpass, String nickname, Integer age, String gender, String email, String phone, Date createTime, Date updateTime, Date lastLogin, Integer userStatus) {
this.name = name;
this.userpass = userpass;
this.nickname = nickname;
this.age = age;
this.gender = gender;
this.email = email;
this.phone = phone;
this.createTime = createTime;
this.updateTime = updateTime;
this.lastLogin = lastLogin;
this.userStatus = userStatus;
}
public Users(Integer id, String nickname, Integer age, String gender, String email, String phone, String remark) {
this.id = id;
this.nickname = nickname;
this.age = age;
this.gender = gender;
this.email = email;
this.phone = phone;
this.remark = remark;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
/*public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}*/
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getUserpass() {
return userpass;
}
public void setUserpass(String userpass) {
this.userpass = userpass;
}
public String getNickname() {
return nickname;
}
public void setNickname(String nickname) {
this.nickname = nickname;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getCreateTime() {
return createTime;
}
public void setCreateTime(Date createTime) {
this.createTime = createTime;
}
public Date getUpdateTime() {
return updateTime;
}
public void setUpdateTime(Date updateTime) {
this.updateTime = updateTime;
}
public Date getLastLogin() {
return lastLogin;
}
public void setLastLogin(Date lastLogin) {
this.lastLogin = lastLogin;
}
public Integer getUserStatus() {
return userStatus;
}
public void setUserStatus(Integer userStatus) {
this.userStatus = userStatus;
}
public String getRemark() {
return remark;
}
public void setRemark(String remark) {
this.remark = remark;
}
public List<Address> getAddresses() {
return addresses;
}
public void setAddresses(List<Address> addresses) {
this.addresses = addresses;
}
@Override
public String toString() {
return "Users{" +
"id=" + id +
", name='" + name + '\'' +
", userpass='" + userpass + '\'' +
", nickname='" + nickname + '\'' +
", age=" + age +
", gender='" + gender + '\'' +
", phone='" + phone + '\'' +
", email='" + email + '\'' +
", createTime=" + createTime +
", updateTime=" + updateTime +
", lastLogin=" + lastLogin +
", userStatus=" + userStatus +
", remark='" + remark + '\'' +
", addresses=" + addresses +
'}';
}
}
/*
Users{id=1, name='damu', userpass='damu', nickname='大慕', age=21,
gender='男', phone='189@163.com', email='18989898989',
createTime=Tue May 16 00:00:00 CST 2017, updateTime=Thu Jun 01 20:05:39 CST 2017, lastLogin=null,
userStatus=1, remark='慕课大牧',
addresses=[Address{id=1, user=null, isDefault=true, province='河南', city='郑州', country='金水区', street='二环路',
remark='瑞隆城7号楼601'},
Address{id=2, user=null, isDefault=false, province='陕西', city='西安', country='北城区', street='开元路', remark='文景小区1号楼202'},
Address{id=3, user=null, isDefault=false, province='云南', city='昆明', country='盘龙区', street='小康大道', remark='银河星辰3号楼402'}]}
*/
<mapper namespace="com.imooc.entity.Users">
<select id="findAll" resultType="com.imooc.entity.Users">
select * from users
</select>
</mapper>
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!-- properties配置，用于加载外部properties配置文件 -->
<properties resource="db.properties"></properties>
<!--
environments 主要用于进行数据源的配置
可以配置多个数据源~ 通过default属性来指定当前项目运行过程中使用的是哪个数据源
-->
<environments default="development">
<!--
environment 用于配置一个具体的独立的数据源
id属性用于给当前数据源定义一个名称，方便我们的项目指定
-->
<environment id="development">
<!--
transactionManager用于配置事务管理，默认情况下使用的是JDBC事务管理
-->
<transactionManager type="JDBC"/>
<!--使用数据库连接池，
dataSource具体数据源的链接信息；type属性用于指定是否使用连接池-->
<dataSource type="POOLED">
<property name="driver" value="${dirver}"/>
<property name="url" value="${url}"/>
<property name="username" value="${username}"/>
<property name="password" value="${password}"/>
</dataSource>
</environment>
</environments>
<!-- 映射配置文件的路径-->
<!-- mappers主要用于配置我们外部的映射配置文件
在主配置文件中需要引入加载映射配置文件
-->
<mappers>
<!-- mapper主要配置引入某一个具体的映射文件，resource进行路径方式的引入 -->
<!--<mapper resource="mapper/usersMapper.xml"/>-->
<mapper resource="mapper/usersMapper.xml"/>
</mappers>
</configuration>
package com.imooc.listener;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;
import com.imooc.util.SqlSessionFactoryUtils;
//之后需要添加监听器配置，才能监听到容器的启动和销毁
@WebListener
//这样监听器就被注册到容器中了
public class InitSqlSessionListener implements ServletContextListener{
//必须让当前的监听器实现servletContextListener
//才能监听到容器的启动和销毁
public void contextInitialized(ServletContextEvent sce) {
System.out.println("容器加载中...");
//初始化我们的SqlSessionFactory对象
SqlSessionFactoryUtils.initSqlSessionFactry();
}
private void contextDestoryed(ServletContextEvent sce) {
System.out.println("容器销毁中...");
// 关闭SqlSession对象
SqlSessionFactoryUtils.close();
}
//之后需要添加监听器配置，才能监听到容器的启动和销毁
}
package com.imooc.servlet;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.imooc.dao.UsersDao;
import com.imooc.entity.Users;
import java.io.IOException;
import java.util.List;
/**
* Created by mouwe on 2017/5/23.
*/
//为了方便和前台进行交互，添加servlet层，
//用于调用DAO中的一些数据
@WebServlet("/index")
public class UsersFindServlet extends HttpServlet {
//直接调用DAO中的操作
private UsersDao usersDao=new UsersDao();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
List<Users>list=usersDao.findAll();
System.out.println(list);
req.setAttribute("usersList", list);
req.getRequestDispatcher("index.jsp").forward(req, resp);
}
}
package com.imooc.util;
import java.io.IOException;
import java.io.InputStream;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
public class SqlSessionFactoryUtils {
private static String RESOURCE = "mybatis.xml";
private static SqlSessionFactory sqlSessionFactory;
//将获取到的sqlSession对象存放在ThreadLocal里进行管理
private static ThreadLocal<SqlSession> threadLocal = new ThreadLocal<SqlSession>();
/**
* 创建一个初始化SqlSessionFactory的方法
*/
public static void initSqlSessionFactry() {
try {
InputStream is = Resources.getResourceAsStream(RESOURCE);
sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 获取工厂对象的方法
* @return
*/
public static SqlSessionFactory getSqlSessionFactory() {
return sqlSessionFactory;
}
/**
* 关闭SqlSession的方法
*/
public static void close(){
SqlSession session = threadLocal.get();
if(session != null) {
session.close();
threadLocal.set(null);
}
}
}
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慕用1236393
2019-10-07 18:39:26
<dataSource type="POOLED">
<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mydb?useSSL=false&serverTimezone=UTC"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</dataSource>
问题算是解决了吧，数据可以显示，就是把properties标签去掉，换成上面的，本来以为是driver单词写错了，可是写对了还是不可以，就得把properties标签去掉，不知道怎么回事
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