CREATE TABLE `bloc` ( 
 
 `id` int(11) NOT NULL auto_increment, 
 
 `name` varchar(255) collate utf8_bin default NULL, 
 
 `company_id` int(11) default NULL, 
 
 `intro` varchar(255) collate utf8_bin default NULL, 
 
 PRIMARY KEY (`id`) 
 
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8 COLLATE=utf8_bin; 
 
 
 
INSERT INTO`bloc` (`id`, `name`, `company_id`, `intro`) VALUES ('1', '宏伟集团', '1', '跨国集团');

CREATE TABLE `company` ( 
 
 `id` int(11) NOT NULL, 
 
 `name` varchar(255) collate utf8_bin default NULL, 
 
 `intro` varchar(255) collate utf8_bin default NULL, 
 
 PRIMARY KEY (`id`) 
 
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin; 
 
INSERT INTO company (`id`, `name`, `intro`) VALUES ('1', '', NULL);

package com.demo.mybatis; 
 
import java.io.IOException; 
import java.io.Reader; 
 
import org.apache.ibatis.io.Resources; 
import org.apache.ibatis.session.SqlSessionFactory; 
import org.apache.ibatis.session.SqlSessionFactoryBuilder; 
 
public class SqlSessionHelper { 
  
 public static SqlSessionFactory getSessionFactory() throws IOException{ 
  SqlSessionFactory sessionFactory = null; 
  Reader reader = Resources.getResourceAsReader("configuration.xml"); 
  try{ 
   sessionFactory = new SqlSessionFactoryBuilder().build(reader);; 
  }catch(Exception ex){ 
   ex.printStackTrace(); 
  } 
  return sessionFactory; 
 } 
}

package com.demo.mybatis; 
 
import java.util.List; 
 
import org.apache.ibatis.session.SqlSession; 
 
import mapper.BlocMapper; 
import model.Bloc; 
 
public class Test { 
 
 /** 
  * @param args 
  */
 public static void main(String[] args) { 
   
  try{ 
   SqlSession sqlSession = SqlSessionHelper.getSessionFactory().openSession(); 
   BlocMapper blocMapper = sqlSession.getMapper(BlocMapper.class); 
   List<Bloc> blocs = blocMapper.getBlocList("1"); 
   for (Bloc bloc : blocs) { 
    System.out.println("companyName = "bloc.getCompany().getName()); 
   } 
  }catch(Exception ex){ 
   System.out.println(ex.getMessage()); 
  } 
 
 } 
 
}

package mapper; 
 
import java.util.List; 
 
import model.Bloc; 
 
public interface BlocMapper { 
 
 public List<Bloc> getBlocList(String name); 
} 

package mapper; 
 
public interface CompanyMapper { 
 
} 

package model; 
 
public class Bloc { 
 
 private Integer id; 
  
 private String name; 
  
 private String intro; 
  
 private Company company; 
 
 public Integer getId() { 
  return id; 
 } 
 
 public void setId(Integer id) { 
  this.id = id; 
 } 
 
 public String getName() { 
  return name; 
 } 
 
 public void setName(String name) { 
  this.name = name; 
 } 
 
 public String getIntro() { 
  return intro; 
 } 
 
 public void setIntro(String intro) { 
  this.intro = intro; 
 } 
 
 public Company getCompany() { 
  return company; 
 } 
 
 public void setCompany(Company company) { 
  this.company = company; 
 } 
  
  
}

package model; 
 
public class Company { 
 
 private Integer id; 
  
 private String name; 
  
 private Integer intro; 
 
 public Integer getId() { 
  return id; 
 } 
 
 public void setId(Integer id) { 
  this.id = id; 
 } 
 
 public String getName() { 
  return name; 
 } 
 
 public void setName(String name) { 
  this.name = name; 
 } 
 
 public Integer getIntro() { 
  return intro; 
 } 
 
 public void setIntro(Integer intro) { 
  this.intro = intro; 
 } 
  
  
}

<?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="mapper.CompanyMapper"> 
  
 <resultMap id="BaseResultMap" type="model.Company" > 
  <id column="id" property="id" jdbcType="INTEGER" /> 
  <result column="name" property="name" jdbcType="VARCHAR" /> 
  <result column="intro" property="intro" jdbcType="VARCHAR" /> 
 </resultMap> 
 <select id = "getCompanyInfo" parameterType="Integer" resultMap="BaseResultMap"> 
  select * from company where id = #{id} 
 </select> 
</mapper> 

<mapper namespace="mapper.BlocMapper">
 <resultMap id="BaseResultMap" type="model.Bloc" >
  <id column="id" property="id" jdbcType="INTEGER" />
  <result column="name" property="name" jdbcType="VARCHAR" />
  <result column="intro" property="intro" jdbcType="VARCHAR" />
  <association column="company_id" property="company" select="mapper.CompanyMapper.getCompanyInfo">
  </association>
 </resultMap>
 
 <select id="getBlocList" parameterType="String" resultMap="BaseResultMap">
  select * from bloc where name = #{name}
 </select>
</mapper>

companyName = 

<?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="mapper.BlocMapper"> 
 <resultMap id="BaseResultMap" type="model.Bloc" > 
  <id column="id" property="id" jdbcType="INTEGER" /> 
  <result column="name" property="name" jdbcType="VARCHAR" /> 
  <result column="intro" property="intro" jdbcType="VARCHAR" /> 
  <!-- 查询会有赋值紊乱问题 --> 
  <association column="company_id" property="company" resultMap = "mapper.CompanyMapper.BaseResultMap"> 
  </association> 
  <!-- <association column="company_id" property="company" select="mapper.CompanyMapper.getCompanyInfo"> 
  </association> --> 
 </resultMap> 
  
 <select id="getBlocList" parameterType="String" resultMap="BaseResultMap"> 
  <!-- select * from bloc where name = #{name} --> 
  <!-- 查询会有赋值紊乱问题 --> 
  select * from bloc b left join company c on b.company_id = c.id where b.name = #{name} 
 </select> 
</mapper>

companyName = 宏伟集团