mybatis 高级映射 简单例子

1.建表

DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
  `gender` varchar(1) NOT NULL,
  `name` varchar(255) NOT NULL,
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `birthday` date DEFAULT NULL,
  `classesid` varchar(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=latin1;

DROP TABLE IF EXISTS `alias`;
CREATE TABLE `alias` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `userid` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=latin1;

DROP TABLE IF EXISTS `classes`;
CREATE TABLE `classes` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `cname` varchar(255) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=latin1;

2.po，vo类

package cn.edu.cqupt.mybatis.po;

import java.io.Serializable;
import java.util.Date;
import java.util.List;

public class User implements Serializable{
    private Integer id;

    private String gender;

    private String name;

    private Date birthday;

    private Classes classes;

    private List<Alias> aliasList;

}

package cn.edu.cqupt.mybatis.po;

import java.io.Serializable;

public class Alias implements Serializable{
    private Integer id;
    private String name;

}

package cn.edu.cqupt.mybatis.po;

public class Classes {
    private Integer id;

    private String cname;

}

目录结构

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" 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3.单表操作    一对多    一对一

1）/testMybatis/src/cn/edu/cqupt/mybatis/mapper/UserMapper.xml
　　/testMybatis/src/cn/edu/cqupt/mybatis/mapper/UserMapper.java

package cn.edu.cqupt.mybatis.mapper;

import cn.edu.cqupt.mybatis.po.User;
import cn.edu.cqupt.mybatis.po.UserClasses;
import cn.edu.cqupt.mybatis.po.UserExample;

import java.util.List;

import org.apache.ibatis.annotations.Param;

public interface UserMapper {
    int countByExample(UserExample example);

    int deleteByExample(UserExample example);

    int deleteByPrimaryKey(Integer id);

    int insert(User record);

    int insertSelective(User record);

    List<User> selectByExample(UserExample example);

    User selectByPrimaryKey(Integer id);

    int updateByExampleSelective(@Param("record") User record, @Param("example") UserExample example);

    int updateByExample(@Param("record") User record, @Param("example") UserExample example);

    int updateByPrimaryKeySelective(User record);

    int updateByPrimaryKey(User record);

    UserClasses selectUserByClasses(Integer classesid);

    User selectUserClass2(Integer classesid);

    User selectUserByAlias(Integer userid);
}

<?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="cn.edu.cqupt.mybatis.mapper.UserMapper" >
  <resultMap id="BaseResultMap" type="cn.edu.cqupt.mybatis.po.User" >
    <id column="id" property="id" jdbcType="INTEGER" />
    <result column="gender" property="gender" jdbcType="VARCHAR" />
    <result column="name" property="name" jdbcType="VARCHAR" />
    <result column="birthday" property="birthday" jdbcType="DATE" />
  </resultMap>
  <sql id="Example_Where_Clause" >
    <where >
      <foreach collection="oredCriteria" item="criteria" separator="or" >
        <if test="criteria.valid" >
          <trim prefix="(" suffix=")" prefixOverrides="and" >
            <foreach collection="criteria.criteria" item="criterion" >
              <choose >
                <when test="criterion.noValue" >
                  and ${criterion.condition}
                </when>
                <when test="criterion.singleValue" >
                  and ${criterion.condition} #{criterion.value}
                </when>
                <when test="criterion.betweenValue" >
                  and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
                </when>
                <when test="criterion.listValue" >
                  and ${criterion.condition}
                  <foreach collection="criterion.value" item="listItem" open="(" close=")" separator="," >
                    #{listItem}
                  </foreach>
                </when>
              </choose>
            </foreach>
          </trim>
        </if>
      </foreach>
    </where>
  </sql>
  <sql id="Update_By_Example_Where_Clause" >
    <where >
      <foreach collection="example.oredCriteria" item="criteria" separator="or" >
        <if test="criteria.valid" >
          <trim prefix="(" suffix=")" prefixOverrides="and" >
            <foreach collection="criteria.criteria" item="criterion" >
              <choose >
                <when test="criterion.noValue" >
                  and ${criterion.condition}
                </when>
                <when test="criterion.singleValue" >
                  and ${criterion.condition} #{criterion.value}
                </when>
                <when test="criterion.betweenValue" >
                  and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
                </when>
                <when test="criterion.listValue" >
                  and ${criterion.condition}
                  <foreach collection="criterion.value" item="listItem" open="(" close=")" separator="," >
                    #{listItem}
                  </foreach>
                </when>
              </choose>
            </foreach>
          </trim>
        </if>
      </foreach>
    </where>
  </sql>
  <sql id="Base_Column_List" >
    id, gender, name, birthday
  </sql>
  <select id="selectByExample" resultMap="BaseResultMap" parameterType="cn.edu.cqupt.mybatis.po.UserExample" >
    select
    <if test="distinct" >
      distinct
    </if>
    <include refid="Base_Column_List" />
    from user
    <if test="_parameter != null" >
      <include refid="Example_Where_Clause" />
    </if>
    <if test="orderByClause != null" >
      order by ${orderByClause}
    </if>
  </select>
  <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    select
    <include refid="Base_Column_List" />
    from user
    where id = #{id,jdbcType=INTEGER}
  </select>
  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
    delete from user
    where id = #{id,jdbcType=INTEGER}
  </delete>
  <delete id="deleteByExample" parameterType="cn.edu.cqupt.mybatis.po.UserExample" >
    delete from user
    <if test="_parameter != null" >
      <include refid="Example_Where_Clause" />
    </if>
  </delete>
  <insert id="insert" parameterType="cn.edu.cqupt.mybatis.po.User" >
    insert into user (id, gender, name,
      birthday)
    values (#{id,jdbcType=INTEGER}, #{gender,jdbcType=VARCHAR}, #{name,jdbcType=VARCHAR},
      #{birthday,jdbcType=DATE})
  </insert>
  <insert id="insertSelective" parameterType="cn.edu.cqupt.mybatis.po.User" >
    insert into user
    <trim prefix="(" suffix=")" suffixOverrides="," >
      <if test="id != null" >
        id,
      </if>
      <if test="gender != null" >
        gender,
      </if>
      <if test="name != null" >
        name,
      </if>
      <if test="birthday != null" >
        birthday,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides="," >
      <if test="id != null" >
        #{id,jdbcType=INTEGER},
      </if>
      <if test="gender != null" >
        #{gender,jdbcType=VARCHAR},
      </if>
      <if test="name != null" >
        #{name,jdbcType=VARCHAR},
      </if>
      <if test="birthday != null" >
        #{birthday,jdbcType=DATE},
      </if>
    </trim>
  </insert>
  <select id="countByExample" parameterType="cn.edu.cqupt.mybatis.po.UserExample" resultType="java.lang.Integer" >
    select count(*) from user
    <if test="_parameter != null" >
      <include refid="Example_Where_Clause" />
    </if>
  </select>
  <update id="updateByExampleSelective" parameterType="map" >
    update user
    <set >
      <if test="record.id != null" >
        id = #{record.id,jdbcType=INTEGER},
      </if>
      <if test="record.gender != null" >
        gender = #{record.gender,jdbcType=VARCHAR},
      </if>
      <if test="record.name != null" >
        name = #{record.name,jdbcType=VARCHAR},
      </if>
      <if test="record.birthday != null" >
        birthday = #{record.birthday,jdbcType=DATE},
      </if>
    </set>
    <if test="_parameter != null" >
      <include refid="Update_By_Example_Where_Clause" />
    </if>
  </update>
  <update id="updateByExample" parameterType="map" >
    update user
    set id = #{record.id,jdbcType=INTEGER},
      gender = #{record.gender,jdbcType=VARCHAR},
      name = #{record.name,jdbcType=VARCHAR},
      birthday = #{record.birthday,jdbcType=DATE}
    <if test="_parameter != null" >
      <include refid="Update_By_Example_Where_Clause" />
    </if>
  </update>
  <update id="updateByPrimaryKeySelective" parameterType="cn.edu.cqupt.mybatis.po.User" >
    update user
    <set >
      <if test="gender != null" >
        gender = #{gender,jdbcType=VARCHAR},
      </if>
      <if test="name != null" >
        name = #{name,jdbcType=VARCHAR},
      </if>
      <if test="birthday != null" >
        birthday = #{birthday,jdbcType=DATE},
      </if>
    </set>
    where id = #{id,jdbcType=INTEGER}
  </update>
  <update id="updateByPrimaryKey" parameterType="cn.edu.cqupt.mybatis.po.User" >
    update user
    set gender = #{gender,jdbcType=VARCHAR},
      name = #{name,jdbcType=VARCHAR},
      birthday = #{birthday,jdbcType=DATE}
    where id = #{id,jdbcType=INTEGER}
  </update>
  <resultMap type="cn.edu.cqupt.mybatis.po.UserClasses" id="user_classes_resultmap">
      <id column="id" property="id"/>
      <result column="gender" property="gender"/>
      <result column="name" property="name"/>
      <result column="birthday" property="birthday"/>

      <association property="classes" javaType="cn.edu.cqupt.mybatis.po.Classes">
        <id column="classesid" property="id"/>
        <result column="cname" property="cname"/>
    </association>
  </resultMap>
  <select id="selectUserByClasses" parameterType="java.lang.Integer" resultMap="user_classes_resultmap">
      select user.*,classes.cname from user
        left join classes on user.classesId=classes.id
        where user.classesId=#{classedid}
  </select>
  <resultMap type="cn.edu.cqupt.mybatis.po.User" id="user_class_resultMap2">
      <id column="id" property="id"/>
      <result column="gender" property="gender"/>
      <result column="name" property="name"/>
      <result column="birthday" property="birthday"/>
      <result column="classesid" property="classesId"/>

  </resultMap>

  <select id="selectUserClass2" parameterType="java.lang.Integer" resultMap="user_class_resultMap2">
      select id,name,gender,birthday,classesid from user
        where classesid=#{classedid}
  </select>

  <resultMap type="cn.edu.cqupt.mybatis.po.User" id="user_alias_resultMap">
      <id column="id" property="id"/>
      <result column="gender" property="gender"/>
      <result column="name" property="name"/>
      <result column="birthday" property="birthday"/>
      <collection property="aliasList" ofType="cn.edu.cqupt.mybatis.po.Alias">
          <id column="aid" property="id"/>
          <result column="aname" property="name"/>
      </collection>
  </resultMap>
  <select id="selectUserByAlias" parameterType="java.lang.Integer" resultMap="user_alias_resultMap">
      select u.*,a.id aid,a.name aname from user u
        left join alias a on a.userid=u.id
    where u.id=#{userid}
  </select>

</mapper>

2）配置  /testMybatis/src/config/SqlMapConfig.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>

    <!-- 加载属性文件 -->
    <properties resource="config/db.properties">
        <!--properties中还可以配置一些属性名和属性值  -->
        <!-- <property name="jdbc.driver" value=""/> -->
    </properties>
    <environments default="development">
        <environment id="development">
        <!-- 使用jdbc事务管理，事务控制由mybatis-->
            <transactionManager type="JDBC" />
        <!-- 数据库连接池，由mybatis管理-->
            <dataSource type="POOLED">
                <property name="driver" value="${jdbc.driver}" />
                <property name="url" value="${jdbc.url}" />
                <property name="username" value="${jdbc.username}" />
                <property name="password" value="${jdbc.password}" />
            </dataSource>
        </environment>
    </environments>
    <!-- 加载 映射文件 -->
    <mappers>
        <package name="cn.edu.cqupt.mybatis.mapper"/>
    </mappers>
</configuration>

3）测试

package cn.edu.cqupt.mybatis.test;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.apache.ibatis.io.Resources;
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 cn.edu.cqupt.mybatis.mapper.UserMapper;
import cn.edu.cqupt.mybatis.po.User;
import cn.edu.cqupt.mybatis.po.UserClasses;
import cn.edu.cqupt.mybatis.po.UserExample;

public class UserMapperTest {

    private SqlSessionFactory sqlSessionFactory;

    @Before
    public void setUp() throws Exception {
        String resource = "config/SqlMapConfig.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        sqlSessionFactory = new SqlSessionFactoryBuilder()
                .build(inputStream);
    }

    @Test
    public void testSelectByPrimaryKey() throws Exception {

        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = userMapper.selectByPrimaryKey(6);

        System.out.println(user);

    }
    @Test
    public void testSelectByExample()throws Exception{
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        UserExample example = new UserExample();
        example.createCriteria().andNameLike("cherry");
        List<User> lists = userMapper.selectByExample(example);
        System.out.println(lists.size());

    }
    @Test
    public void testUpdateByPrimaryKey()throws Exception{
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = userMapper.selectByPrimaryKey(3);
        user.setName("aa");
        user.setBirthday(new Date());
        userMapper.updateByPrimaryKey(user);
        sqlSession.commit();
        sqlSession.close();
    }

    @Test
    public void testInsert()throws Exception{
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = new User();
        user.setName("lll");
        user.setGender("2");
        user.setBirthday(new Date());
        int count = userMapper.insert(user);
        sqlSession.commit();
        sqlSession.close();
    }
    @Test
    public void selectUserByClasses(){
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        UserClasses uc=userMapper.selectUserByClasses(new Integer(1));
        System.out.println(uc.toString());

    }

    @Test
    public void selectUserClass2(){
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        userMapper.selectUserClass2(new Integer(1));

    }
    @Test
    public void selectUserByAlias(){
        SqlSession sqlSession = sqlSessionFactory.openSession();
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user = userMapper.selectUserByAlias(new Integer(2));
        System.out.println(user.getAliasList().size());
    }

}