<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mapper namespace="dao.EmployeeDAO"><!-- 命名空间等于接口的完整名字，包名加接口名 --><!-- id要求唯一 parameterType:填写实体类的完整名字--><!-- 插入语句 --><insert id="save" parameterType="entity.Employee">INSERT INTO T_TABLE VALUES(2,#{name},#{age})</insert><!-- 根据id查询语句 --><select id="findByID" parameterType="int" resultType="entity.Employee">SELECT * FROM T_TABLE WHERE ID=#{id}</select><!-- 查询所有结果,不需要参数类型 --><select id="findAll" resultType="entity.Employee">SELECT * FROM T_TABLE</select><!-- 修改操作 --><update id="modify" parameterType="entity.Employee">UPDATE T_TABLE SET NAME=#{name},AGE=#{age} WHERE ID=#{id}</update><!-- 删除操作 --><delete id="delete" parameterType="int">DELETE FROM T_TABLE WHERE ID=#{ididid} </delete><!-- 返回map类型的结果 --><!-- 也可以将返回结果简写成map，map即为java.util.Map --><select id="findOne" parameterType="int" resultType="java.util.Map">SELECT * FROM T_TABLE WHERE ID=#{id}</select><!-- 使用resultMap解决表的字段名和实体类的属性名不一致的情况 --><resultMap id="resultMapID" type="entity.NewEmployee"><result property="empID" column="id" /><result property="empName" column="name" /><result property="empAge" column="age" /></resultMap><select id="findOneByNewEmp" parameterType="int" resultMap="resultMapID">SELECT * FROM T_TABLE WHERE ID=#{id}</select></mapper>

import java.util.List;
import java.util.Map;import entity.Employee;
import entity.NewEmployee;/*** Mapper映射器* @author*/
public interface EmployeeDAO {    //将一条数据插入数据库public void save(Employee e);//查询所有结果public List<Employee> findAll();//根据id来查找结果public Employee findByID(int id);//修改操作public void modify(Employee e);//删除操作public void delete(int id);//返回类型为map的查询，根据id来查询public Map findOne(int id);//当表的字段名和实体类的属性名不一致时，根据id来查询public NewEmployee findOneByNewEmp(int id);
}

import java.util.List;
import java.util.Map;import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test;import dao.EmployeeDAO;
import entity.Employee;
import entity.NewEmployee;public class testMapper {//先拿到sqlSessionprivate SqlSession session;@Beforepublic void init() {String config="SqlMapConfig.xml";SqlSessionFactoryBuilder ssfb=new SqlSessionFactoryBuilder();//读取SqlMapConfig.xml文件，预编译sql写入mapSqlSessionFactory ssf=ssfb.build(testMapper.class.getClassLoader().getResourceAsStream(config));session=ssf.openSession();        }//测试mapper映射器 插入记录
        @Testpublic void test1() {//mybatis会返回一个符合mapper映射器要求的对象EmployeeDAO dao=session.getMapper(EmployeeDAO.class);            Employee e=new Employee();e.setName("qiaofeng");e.setAge(38);//调用对象的插入方法
            dao.save(e);//提交事务s
            session.commit();session.close();}/*** 查询所有员工操作*/@Testpublic void test2() {//mybatis会返回一个符合mapper映射器要求的对象EmployeeDAO dao=session.getMapper(EmployeeDAO.class);List<Employee> list=dao.findAll();System.out.println(list);session.close();}/*** 根据ID来查找员工信息*/@Testpublic void test3() {EmployeeDAO dao=session.getMapper(EmployeeDAO.class);Employee emp=dao.findByID(2);System.out.println(emp);session.close();}/*** 修改操作*/@Testpublic void test4() {EmployeeDAO dao=session.getMapper(EmployeeDAO.class);Employee emp=dao.findByID(2);emp.setAge(emp.getAge()*2);//修改
            dao.modify(emp);session.commit();session.close();}/*** 删除操作*/@Testpublic void test5() {EmployeeDAO dao=session.getMapper(EmployeeDAO.class);dao.delete(5);session.commit();session.close();}
}