Mybatis使用Mapper方式CURD

Mybatis 使用Dao代码方式进行增、删、改、查和分页查询。

1、Maven的pom.xml

2、配置文件

2.1、db.properties

2.2、mybatis.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>

     <!-- 配置属性，加载数据库配置参数 -->
     <properties resource="db.properties"></properties>

      <!-- 使用别名 -->
     <typeAliases>
         <!-- 为包下的所有文件设置别名，别名为类名，不分大小写 -->
         <package name="com.mcs.entity"/>
     </typeAliases>

     <!-- 和Spring整合后environments配置将废除 -->
     <environments default="mysql_developer">
         <environment id="mysql_developer">
             <!-- mybatis使用jdbc事务管理方式 -->
             <transactionManager type="JDBC" />
             <!-- mybatis使用连接池方式来获取连接 -->
             <dataSource type="POOLED">
                 <!-- 配置与数据库交互的4个必要属性 -->
                 <property name="driver" value="${jdbc.driverClass}" />
                 <property name="url" value="${jdbc.jdbcUrl}" />
                 <property name="username" value="${jdbc.user}" />
                 <property name="password" value="${jdbc.password}" />
             </dataSource>
         </environment>
     </environments>

     <!-- 加载映射文件     -->
     <mappers>
         <!-- 自动加载包下的所有映射文件 -->
         <package name="com.mcs.mapper"/>
     </mappers>

 </configuration>

2.3、log4j.xml

3、MybatisUtil工具类

4、Mapper映射文件

 <?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" >
 <mapper namespace="com.mcs.mapper.EmployeeMapper">
     <resultMap id="employeeResultMap" type="com.mcs.entity.Employee">
         <id column="id" property="id" jdbcType="INTEGER" />
         <result column="name" property="name" jdbcType="VARCHAR" />
         <result column="sex" property="sex" jdbcType="VARCHAR" />
         <result column="birthday" property="birthday" jdbcType="DATE" />
         <result column="email" property="email" jdbcType="VARCHAR" />
         <result column="telephone" property="telephone" jdbcType="VARCHAR" />
         <result column="cellphone" property="cellphone" jdbcType="VARCHAR" />
         <result column="address" property="address" jdbcType="VARCHAR" />
         <result column="department_id" property="departmentId" jdbcType="INTEGER" />
     </resultMap>

     <!-- 新增职员，并返回插入后的ID值 -->
     <insert id="add" keyColumn="id" keyProperty="id" useGeneratedKeys="true" parameterType="Employee">
         insert into t_employee
         ( name, sex, birthday, email, telephone, cellphone, address, department_id )
         values
         ( #{name}, #{sex}, #{birthday}, #{email}, #{telephone}, #{cellphone}, #{address}, #{departmentId} )
     </insert>

     <update id="updateById" parameterType="Employee">
         update t_employee
         set name = #{name,jdbcType=VARCHAR},
             sex = #{sex,jdbcType=VARCHAR},
             birthday = #{birthday,jdbcType=DATE},
             email = #{email,jdbcType=VARCHAR},
             telephone = #{telephone,jdbcType=VARCHAR},
             cellphone = #{cellphone,jdbcType=VARCHAR},
             address = #{address,jdbcType=VARCHAR},
             department_id = #{departmentId,jdbcType=INTEGER}
         where id = #{id,jdbcType=INTEGER}
     </update>

     <delete id="deleteById" parameterType="Integer" >
         delete from t_employee
         where id = #{id}
     </delete>

     <select id="findById"  parameterType="Integer" resultMap="employeeResultMap">
         select
             id,name, sex, birthday, email, telephone, cellphone, address, department_id
         from t_employee
         where id = #{id}
     </select>

     <select id="findAll" resultMap="employeeResultMap">
         select
             id,name, sex, birthday, email, telephone, cellphone, address, department_id
         from t_employee
     </select>

     <!-- 分页无条件查询所有员工信息 -->
     <select id="findAllWithPage"  parameterType="map" resultMap="employeeResultMap">
         select
             id,name, sex, birthday, email, telephone, cellphone, address, department_id
         from t_employee
             limit #{pstart}, #{psize}
     </select>

 </mapper>

5、Mapper映射文件对应的接口文件

 package com.mcs.mapper;

 import java.util.List;
 import java.util.Map;

 import com.mcs.entity.Employee;

 public interface EmployeeMapper  {

     public void add(Employee employee) throws Exception;
     public void updateById(Employee employee) throws Exception;
     public void deleteById(Integer id) throws Exception;
     public Employee findById(Integer id) throws Exception;
     public List<Employee> findAll() throws Exception;
     public List<Employee> findAllWithPage(Map<String, Object> pageMap) throws Exception; 

 }

此文件应与Mapper在同一命名空间下

6、测试代码

 package com.mcs.test;

 import java.util.Date;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;

 import org.apache.ibatis.session.SqlSession;
 import org.apache.log4j.Logger;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;

 import com.mcs.entity.Employee;
 import com.mcs.mapper.EmployeeMapper;
 import com.mcs.util.MybatisUtil;

 public class TestEmployeeMapper {
     /**
     * Logger for this class
     */
     private static final Logger logger = Logger.getLogger(TestEmployeeMapper.class);

     private EmployeeMapper employeeMapper;
     private SqlSession sqlSession = null;

     @Before
     public void init() {
         sqlSession = MybatisUtil.getSqlSession();
         employeeMapper = sqlSession.getMapper(EmployeeMapper.class);
     }

     @After
     public void destory() {
         MybatisUtil.closeSqlSession();
     }

     @Test
     public void testFindById() throws Exception {
         Employee employee = employeeMapper.findById();
         logger.debug(employee);
     }

     @Test
     public void testFindAll() throws Exception {
         List<Employee> employees = employeeMapper.findAll();
         logger.debug(employees);
     }

     @Test
     public void testAdd() throws Exception {
         Employee employee = new Employee();
         employee.setName("赵小凤");
         employee.setSex("female");
         employee.setBirthday(new Date());
         employee.setEmail("xiaofeng@126.com");
         try {
             employeeMapper.add(employee);
             sqlSession.commit();
         } catch (Exception e) {
             e.printStackTrace();
             sqlSession.rollback();
             throw e;
         }        

         logger.debug(employee);
     }

     @Test
     public void testEditById() throws Exception {
         Employee employee = employeeMapper.findById();
         employee.setDepartmentId();
         employee.setAddress("天津");        

         try {
             employeeMapper.updateById(employee);
             sqlSession.commit();
         } catch (Exception e) {
             e.printStackTrace();
             sqlSession.rollback();
             throw e;
         }        

         logger.debug(employee);
     }

     @Test
     public void testDeleteById() throws Exception {
         Employee employee = employeeMapper.findById();
         logger.debug(employee);
         try {
             employeeMapper.deleteById();
             sqlSession.commit();
         } catch (Exception e) {
             e.printStackTrace();
             sqlSession.rollback();
             throw e;
         }                

         logger.debug("已成功删除员工："  + employee.getName());
     }

     @Test
     public void testFindAllWithPage()throws Exception {
         Map<String, Object> pageMap = new LinkedHashMap<String, Object>();
         Integer start = ;
         Integer size = ;
         pageMap.put("pstart", start);
         pageMap.put("psize", size);

         List<Employee> employees = employeeMapper.findAllWithPage(pageMap);

         logger.debug(employees);
     } 

 }