mybatis执行过程解析

一、配置文件解析

配置文件的结构

mybatis-config.xml

<configuration>
    <properties resource="config/database.properties"/>
    <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>
    <mappers>
        <mapper resource="mybatis/customerMapper.xml"/>
    </mappers>
</configuration>

xxxMapper.xml

<mapper namespace="com.huawei.esight.customer.mapper.CustomerMapper">
    <select id="selectById" resultType="com.huawei.esight.customer.model.Customer">
        SELECT * FROM customer where id = #{id}
    </select>
    <insert></insert>
    <delete></delete>
    <update></update>
</mapper>

配置文件的解析流程即将上述的XML文件元素转换成对应的Java对象过程，其最终的转换对象及其关系如下图：

配置元素解析构造器

org.apache.ibatis.builder.xml.XMLConfigBuilder
    
org.apache.ibatis.builder.xml.XMLMapperBuilder
    
org.apache.ibatis.builder.xml.XMLStatementBuilder

SqlStatement构建流程

【mybatis-config.xml文件解析】
org.apache.ibatis.builder.xml.XMLConfigBuilder#parse

org.apache.ibatis.builder.xml.XMLConfigBuilder#parseConfiguration

org.apache.ibatis.builder.xml.XMLConfigBuilder#mapperElement

【mapper.xml文件解析】
org.apache.ibatis.builder.xml.XMLMapperBuilder#parse

org.apache.ibatis.builder.xml.XMLMapperBuilder#configurationElement

org.apache.ibatis.builder.xml.XMLMapperBuilder#buildStatementFromContext

【statement sql块解析】
org.apache.ibatis.builder.xml.XMLStatementBuilder#parseStatementNode

org.apache.ibatis.builder.MapperBuilderAssistant#addMappedStatement

二、会话创建 SqlSession

SqlSession对象结构

未完待续。。。