本文共 3858 字，大约阅读时间需要 12 分钟。

建表

create table student(id int(10) primary key,name varchar(20) default null,tid int(10) default null,foreign key(tid) references teacher(id))insert into teacher values(1,'秦老师');insert into student values(1,'小明',1);insert into student values(2,'小红',1);insert into student values(3,'小张',1);insert into student values(4,'小李',1);insert into student values(5,'小王',1);

接口

package com.tjrac.dao;import com.tjrac.pojo.Teacher;import com.tjrac.pojo.User;import org.apache.ibatis.annotations.Param;import org.apache.ibatis.annotations.Select;import java.util.List;import java.util.Map;public interface TeacherMapper {
       //查询全部用户    List
   
     getTeacherList(int i);}
   

package com.tjrac.dao;import com.tjrac.pojo.Student;import com.tjrac.pojo.Teacher;import org.apache.ibatis.annotations.Select;import java.util.List;public interface StudentMapper {
       List
   
     getStudentList();    List
    
      getStudentList2();}
    
   

实体类

package com.tjrac.pojo;import lombok.AllArgsConstructor;import lombok.Data;import lombok.NoArgsConstructor;@Data@NoArgsConstructor@AllArgsConstructorpublic class Student {
       private  int id;    private  String name;    private Teacher teacher;}

package com.tjrac.pojo;import lombok.AllArgsConstructor;import lombok.Data;import lombok.NoArgsConstructor;import lombok.ToString;@Data@NoArgsConstructor@AllArgsConstructorpublic class Teacher {
       private int id;    private  String name;}

配置文件

StudentMapper.xml
   
   
       
        
          select student.id,student.name,teacher.name as tname from student,teacher where student.tid=teacher.id        
            
             
             
                 
              
         
        
        
        
          select * from student        
          select * from teacher where id=#{
   id}        
            
             
             
         
    
   

TeacherMapper.xml
   
   
       
          select * from teacher where id=#{
   id}    
   

mybatis-config.xml
   
   
       
        
        
            
                 
                  
                      
                       
                       
                       
                       
                   
              
         
        
            
             
         
    
   

测试类

package com.tjrac.dao;import com.tjrac.pojo.Student;import com.tjrac.pojo.Teacher;import com.tjrac.pojo.User;import com.tjrac.utils.MybatisUtils;import org.apache.ibatis.session.SqlSession;import org.junit.Test;import java.util.HashMap;import java.util.List;import java.util.Map;public class Mytest {
       @Test    public void getTeacherList(){
           //第一步：获取SqlSession对象        SqlSession sqlSession = MybatisUtils.getSqlSession();        //第二步：执行SQL        TeacherMapper teacherDao= sqlSession.getMapper(TeacherMapper.class);        List
   
     list=teacherDao.getTeacherList(1);        for(Teacher t: list){
               System.out.println(t.toString());        }        sqlSession.close();    }    @Test    public void getStudentList(){
           //第一步：获取SqlSession对象        SqlSession sqlSession = MybatisUtils.getSqlSession();        //第二步：执行SQL        StudentMapper teacherDao= sqlSession.getMapper(StudentMapper.class);        List
    
      list=teacherDao.getStudentList();        for(Student t: list){
               System.out.println(t.toString());        }        sqlSession.close();    }    @Test    public void getStudentList2(){
           //第一步：获取SqlSession对象        SqlSession sqlSession = MybatisUtils.getSqlSession();        //第二步：执行SQL        StudentMapper teacherDao= sqlSession.getMapper(StudentMapper.class);        List
     
       list=teacherDao.getStudentList();        for(Student t: list){
               System.out.println(t.toString());        }        sqlSession.close();    }}
     
    
   

转载地址：http://xlrwi.baihongyu.com/