mybatis 配置文件

解析配置文件

1. 配置mybatis-config.xml

<?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>
    // 引入properties文件，resource表示读取本项目中的属性文件，url读取远程属性文件,二者不能同时存在，否则报异常，从下文中的源码中可以看到
    <!--<properties resource="classpath:app.properties"></properties>-->
    <!--<properties url="http://localhost:8000/mybatis/app.properties"></properties>-->
    <settings>
        <!-- 使用jdbc的getGeneratedKeys获取数据库自增主键值 -->
        <setting name="useGeneratedKeys" value="true" />

        <!-- 使用列别名替换列名 默认:true -->
        <setting name="useColumnLabel" value="true" />

        <!-- 开启驼峰命名转换:Table{create_time} -> Entity{createTime} -->
        <setting name="mapUnderscoreToCamelCase" value="true" />
    </settings>
    <!-- 自定义typeHandle，将TIMESTAMP转为long -->
    <typeHandlers>
        <typeHandler handler="com.ws.mybatis.dao.LongTimeHandler" javaType="long" jdbcType="TIMESTAMP"/>
    </typeHandlers>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://127.0.0.1:3306/test?serverTimezone=GMT%2B8"/>
                <property name="username" value="root"/>
                <property name="password" value="sidNkyy6h0wkNinH"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="UserInfoMapper.xml"/>
       <!-- <mapper class="com/ws/mybatis/dao/UserInfoMapper"/>-->
    </mappers>
</configuration>

app.properties

jdbc.url=jdbc:mysql://127.0.0.1:3306/test?serverTimezone=GMT%2B8
jdbc.username=root
jdbc.password=123456

UserInfoMapper.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.ws.mybatis.dao.UserInfoMapper">
    <resultMap id="BaseResultMap" type="com.ws.mybatis.model.UserInfo">
        <id column="id" jdbcType="INTEGER" property="id" />
        <result column="name_str" jdbcType="VARCHAR" property="nameStr" />
        <result column="age" jdbcType="INTEGER" property="age" />
        <result column="salary" jdbcType="DECIMAL" property="salary" />
        <result column="address" jdbcType="VARCHAR" property="address" />
        <result column="phone" jdbcType="VARCHAR" property="phone" />
        <result column="update_time" jdbcType="TIMESTAMP" property="updateTime" />
        <!-- 添加类型映射 -->
        <result column="update_long_time" jdbcType="TIMESTAMP" property="updateLongTime" />
    </resultMap>
    <sql id="BaseTable">
        user_info
    </sql>
    <select id="get" resultMap="BaseResultMap" parameterType="java.lang.Object" >
     select id,name_str,age
        from user_info
        where id = #{id,jdbcType=INTEGER}
    </select>

    <select id="getById" resultMap="BaseResultMap" parameterType="java.lang.Object" >
     select u.*,u.update_time as update_long_time
        from user_info u
        where id = #{id,jdbcType=INTEGER}
    </select>


    <insert id="insert" parameterType="com.ws.mybatis.model.UserInfo" useGeneratedKeys="true" keyProperty="id">
        insert into user_info(id,name_str,age)
            values (#{id, jdbcType=INTEGER},#{nameStr, jdbcType=VARCHAR},#{age, jdbcType=INTEGER})
    </insert>
</mapper>