mybatis chapter1

MyBatis 快速入门

Mybatis示例

配置文件

<?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"/>
    <configuration>
        <properites>
            <property name = "username" value ="root"/>
            <property name = "id" value = "123"/>
        </properites>
        <settings>
            <setting name="cacheEnabled" value = "true"/>
        </settings>
        <typeAliases>
            <typeAlias type = "com.xxx.Blog" alias = "Blog"/>
        </typeAliases>
        <enviroments default = "development">
            <enviroment id = "development">
                <transcationManager type="JDBC"/>
                <dataSource type="POOLED">
                    <property name="driver" value = "com.mysql.jdbc.Driver"/>
                    <property name="url" value="jdbc:mysql://localhost:3306/test"/>
                    <property name="username" value="root"/>
                    <property name="password" value=""/>
                </dataSource>
            </enviroment>
        </enviroments>
        <mappers>
            <mapper resource="com/***/BlogMapper.xml"/>
        </mappers>            
    </configuration>
</xml>

执行的java代码

class Main {
    public static void main(String[] args) throws Exception {
        String resource = "com/xxx/mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuillder().build(inputStream);

        SqlSession sqlsession = sqlSessionFactory.openSession();
        try {
            Map<String,Object> parameter = new HashMap<>();
            parameter.put("id", 1);
            Blog blog = sqlSession.selectOne("com.xxx.BlogMapper.selectBlogDetails", parameter);
            //
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
}

MyBatis 整体架构

基础支持层

• 反射模块

• 类型转换模块

  jdbcType和JavaType之间类型做转换

• 日志模块

• 资源加载模块

  对类加载器进行封装

• 解析器模块

  对Xpath进行封装 为config处理提供支持

  为处理sql语言中的占位符提供支持

• 数据源模块

• 事务管理

• 缓存模块

• Binding模块

核心处理层

• 配置解析

• Sql解析与sripting 模块

• Sql执行

  sqlSession -> executor -> statementHandler -> parameterHandler -> statement -> db -> resultSet ->ResultSetHandler -> StatementHandler ->executor -> sqlSession