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(1);
        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(13);
        employee.setDepartmentId(3);
        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(13);
        logger.debug(employee);
        try {
            employeeMapper.deleteById(13);
            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 = 6;
        Integer size = 3;
        pageMap.put("pstart", start);
        pageMap.put("psize", size);
        
        List<Employee> employees = employeeMapper.findAllWithPage(pageMap);
        
        logger.debug(employees);
    } 

}