Mybatis核心配置文件之多环境配置

<mapper namespace="a">
    <insert id="insertCar">
        INSERT INTO t_car
        VALUES (null, "666", "QQ", 30.0, "2020-11-11", "燃油车");
    </insert>
</mapper>

    @Test
    public void testEnvironmentA() throws Exception {
        //获取的默认环境（default="DBa"）
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("mybatis-config.xml"));
        SqlSession sqlSession = sqlSessionFactory.openSession();
        sqlSession.insert("insertCar");
        sqlSession.commit();
        sqlSession.close();
    }

    @Test
    public void testEnvironmentB() throws Exception {
        //通过环境id来使用指定的环境
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("mybatis-config.xml"),"DBb");
        SqlSession sqlSession = sqlSessionFactory.openSession();
        sqlSession.insert("insertCar");
        sqlSession.commit();
        sqlSession.close();
    }

 <environments default="DBa">
        <environment id="DBa">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/lonely01"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
        <environment id="DBb">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/lonely"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>