<?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 resource="db.properties" />

    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <typeAliases>
        <package name="com.liu.pojo" />
    </typeAliases>


    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="${driver}"/>
                <property name="url" value="${url}"/>
                <property name="username" value="${username}"/>
                <property name="password" value="${password}"/>
            </dataSource>
        </environment>
    </environments>
<!--绑定接口-->
    <mappers>
        <package name="com.liu.dao"/>
    </mappers>

</configuration>

 db.properties

driver=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/jdbc?useSSL=true&allowPublicKeyRetrieval=true&serverTimezone=UTC
username=root
password=root

MybatisUtils

package com.liu.utils;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;

public class MybatisUtils {
    private static SqlSessionFactory sqlSessionFactory;

    static {
       try {
           String resource="mybatis-config.xml";
           InputStream inputStream = Resources.getResourceAsStream(resource);
           sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
       } catch (IOException e) {
           e.printStackTrace();
       }

    }
    public  static SqlSession getSqlSession(){
        return  sqlSessionFactory.openSession();
    }

}