MyBatis （一）基本步骤

1.com.pojo

1) 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>    <!--环境配置：默认开发模式-->    <environments default="development">        <environment id="development">            <!--JDBC进行事务管理-->            <transactionManager type="JDBC"/>            <!--数据源配置：底层连接池-->            <dataSource type="POOLED">                <property name="driver" value="com.mysql.jdbc.Driver"/>                <property name="url" value="jdbc:mysql://localhost:3306/student?characterEncoding=utf8"/>                <property name="username" value="root"/>                <property name="password" value="123"/>            </dataSource>        </environment>    </environments>    <!--注册映射 XML 文件-->    <mappers>        <mapper resource="com/pojo/mapper/StudentMapper.xml"/>    </mappers></configuration>

2)实体类

2.com.util

1)mybatisUtil.java

public class MyBatisUtil {    private static SqlSessionFactory sqlSessionFactory = null;    static {        try {            InputStream is = Resources.getResourceAsStream("com/pojo/pojo/mybatis-config.xml");            sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);        } catch (IOException e) {            e.printStackTrace();            System.out.println("配置文件解析问题");        }    }    public static SqlSession getSqlSession(boolean isCommit){        return sqlSessionFactory.openSession(isCommit);    }}

3.com.mapper

1) StudentMapper.xml

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE mapper PUBLIC "-//mybatis.org/DTD Mapper 3.0" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><!--无代理：namespace：值是任意的，一般是映射接口全路径--><!--有代理：namespace：值映射接口全路径--><!--项目中所有的映射 XML 中 namespace 值是唯一的--><mapper namespace="abc">    <!-- //  查询所有-->    <select id="findAll" resultType="com.pojo.pojo.StudentInfo">        select * from StudentInfo    </select>    <!--// 查询单条-->    <select id="findAllBySid" resultType="com.pojo.pojo.StudentInfo"    parameterType="Integer">        SELECT  * from StudentInfo        WHERE        sid=#{sid}    </select>    <!--// 根据主键修改-->    <update id="updateBySid" parameterType="com.pojo.pojo.StudentInfo">        update StudentInfo        set        sname=#{sname},        sgender=#{sgender},        sage=#{sage},        saddress=#{saddress},        semail=#{semail}        WHERE        sid=#{sid}    </update></mapper>

2)StudentMapper接口定义方法

4.com.mapper.IMP

1) StudentMapperIMP

重写的方法：1)SqlSession sqlSession = MyBatisUtil.getSqlSession(false);2)sqlSession.selectList("abc.findAll");  sqlSession.selectOne("abc.findAllBySid",sid);  sqlSession.update("abc.updateBySid",studentInfo);<!--// namespace.id-->3)sqlSession.close();