mybatis入门使用4：返回对象方式

mybatis将查询出的ResultSet封装成了对象，可以有以下2种写法：

1、resultMap="BaseResultMap"

2、resultType="com.lls.model.Employee"

<?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">
<mapper namespace="com.lls.mapper.EmployeeMapper">
<resultMap id="BaseResultMap" type="com.lls.model.Employee">
<id column="ID" jdbcType="INTEGER" property="id" />
<result column="EmployeeName" jdbcType="VARCHAR" property="employeename" />
<result column="Position" jdbcType="VARCHAR" property="position" />
<result column="Salary" jdbcType="DOUBLE" property="salary" />
<result column="Tel" jdbcType="VARCHAR" property="tel" />
<result column="DepartmentID" jdbcType="INTEGER" property="departmentid" />
</resultMap>
<sql id="Base_Column_List">
ID, EmployeeName, Position, Salary, Tel, DepartmentID
</sql>

<select id="selectByEmpName" parameterType="java.lang.String" resultType="com.lls.model.Employee">
select
ID as id,
EmployeeName as employeename,
Position as position,
Salary as salary
from t_employee
where EmployeeName like CONCAT ("%",#{name,jdbcType=VARCHAR},"%")
</select>

<select id="selectHighestSalary" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from t_employee
where Salary in (select Max(Salary) from t_employee)
</select>

</mapper>

测试：

package com.lls.test;

import java.util.List;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.lls.mapper.EmployeeMapper;
import com.lls.model.Employee;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:config/spring-mybatis.xml"})
public class MyBatisSelectReturn {

private static final Logger LOGGER = LoggerFactory.getLogger(MyBatisSelectReturn.class);

@Autowired
private EmployeeMapper employeeMapper;

@Test
public void testResultMap() {
/*
* 在本model对应的 xml中写 <sql> <include refid="Base_Column_List" /> 更快更方便维护
*/
List<Employee> employees = employeeMapper.selectHighestSalary();
LOGGER.info("testResultMap employees.size: "+ employees.size());
}

@Test
public void testResultType() {
/*
* 在其他model对应的 xml中写 <resultType> 可以减少没必要的 xml和 mapper
*/
List<Employee> employees = employeeMapper.selectByEmpName("A");
LOGGER.info("testResultType employees.size: "+ employees.size());
}

}

代码文档：http://download.csdn.net/download/lanlianhua_luffy/9869769