MyBatis配置

主配置文件，放入src下

<?xml version="1.0" encoding="UTF-8" ?>  
<!DOCTYPE configuration PUBLIC "-//ibatis.apache.org//DTD Config 3.0//EN" 
    "http://ibatis.apache.org/dtd/ibatis-3-config.dtd">
<configuration>
    <environments default="mysql">
        <!-- MySQL -->
        <environment id="mysql">
            <!-- JDBC提交和回滚机制 -->
            <transactionManager type="JDBC"/>
            <!-- JDBC连接对象的数据源连接池的实现 -->
            <dataSource type="POOLED">
                <property name="driver" 
                    value="com.mysql.jdbc.Driver"/>
                <property name="url" 
                    value="jdbc:mysql://127.0.0.1:3306/test"/>
                <property name="username" value="root"/>
                <property name="password" value="1234"/>        
            </dataSource>
        </environment>    
        
        <!-- Oracle -->
    </environments>
    
    <!-- 关联映射文件 -->
    <mappers>
        <mapper resource="com/xms/entity/mapper/EmpMapper.xml"/>
        <mapper resource="com/xms/entity/mapper/DeptMapper.xml"/>
    </mappers>
    
</configuration>    
    

mapper放在com.xms.entity.mapper下，它的命名空间和id是跟EmpMapper.java接口一一对应的

EmpMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>  
<!DOCTYPE mapper PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN"      
 "http://ibatis.apache.org/dtd/ibatis-3-mapper.dtd">
<mapper namespace="com.xms.dao.EmpMapper">
    <select id="findAll" resultType="com.xms.entity.Emp">
        select * from emp
    </select>
</mapper> 

EmpMapper.java    放在com.xms.dao下

package com.xms.dao;

import java.util.List;

import com.xms.entity.Emp;

public interface EmpMapper {
    
    List<Emp> findAll();
    
    Emp findByEmpno(int empno);
    
    void save(Emp emp);
    
    void update(Emp emp);
    
    void delete(Emp emp);
    
}

MyBatisUtil.java   放在com.xms.util下，加载配置文件，获得SqlSession

package com.xms.util;  

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class MyBatisUtil {
    
    private static SqlSessionFactory ssf;
    
    static{
        //加载配置文件
        SqlSessionFactoryBuilder ssfb = 
            new SqlSessionFactoryBuilder();
        ssf = ssfb.build(MyBatisUtil.class
            .getClassLoader().getResourceAsStream("iBatis.xml"));
    }
    
    //获取SqlSession
    public static SqlSession getSession(){
        return ssf.openSession();
    }
    
    public static void main(String[] args) {
        System.out.println(MyBatisUtil.getSession());
    }
    
}

参考文件SpringMyBatisDay06_02