在dao中使用注解:

package cn.dao;

import cn.mepu.User;
import org.apache.ibatis.annotations.Select;

import java.util.List;

/**
 * @author shkstart
 * @create 2019-11-01 10:25
 */
public interface UserDao {

    //创建查询所有方法
    @Select("select * from user")
    List<User> findAll();

}

使用注解删除dao.xml的配置文件更改主配置文件为;

<?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>
    <environments default="mysql">
        <environment id="mysql">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/javaee"/>
                <property name="username" value="root"/>
                <property name="password" value="root"/>
            </dataSource>
        </environment>
    </environments>
<!--    指定映射文件-->
    <mappers>
        <mapper class="cn.dao.UserDao"></mapper>
    </mappers>
</configuration>
12-30 16:38