mybatis学习一：基于xml与注解配置入门实例与问题

  1 package com.ys.test;
  2  
  3 import java.io.InputStream;
  4 import java.util.List;
  5  
  6 import org.apache.ibatis.session.SqlSession;
  7 import org.apache.ibatis.session.SqlSessionFactory;
  8 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
  9 import org.junit.Before;
 10 import org.junit.Test;
 11  
 14 public class CRUDTest {
 15     //定义 SqlSession
 16     SqlSession session =null;
 17      
 18     @Before
 19     public void init(){
 20         //定义mybatis全局配置文件
 21         String resource = "mybatis-configuration.xml";
 22         //加载 mybatis 全局配置文件
 23         InputStream inputStream = CRUDTest.class.getClassLoader().getResourceAsStream(resource);
 25         //构建sqlSession的工厂
 26         SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
 27         //根据 sqlSessionFactory 产生 session
 28         session = sessionFactory.openSession();
 29     }
 30      
 31     //根据id查询user表数据
 32     @Test
 33     public void testSelectUserById(){
 34         /*这个字符串由 userMapper.xml 文件中 两个部分构成
 35             <mapper namespace="user"> 的 namespace 的值
 36             <select >*/
 37         String statement = "user.selectUserById";
 38         User user = session.selectOne(statement, 1);
 39         System.out.println(user);
 40         session.close();
 41     }
 42      
 43     //查询所有user表所有数据
 44     @Test
 45     public void testSelectUserAll(){
 46         String statement = "user.selectUserAll";
 47         List<User> listUser = session.selectList(statement);
 48         for(User user : listUser){
 49             System.out.println(user);
 50         }
 51         session.close();
 52     }
 53      
 54     //模糊查询：根据 user 表的username字段
 55     @Test
 56     public void testSelectLikeUserName(){
 57         String statement = "user.selectLikeUserName";
 58         List<User> listUser = session.selectList(statement, "%t%");
 59         for(User user : listUser){
 60             System.out.println(user);
 61         }
 62         session.close();
 63          
 64     }
 65     //向 user 表中插入一条数据
 66     @Test
 67     public void testInsertUser(){
 68         String statement = "user.insertUser";
 69         User user = new User();
 70         user.setUsername("Bob");
 71         user.setSex("女");
 72         session.insert(statement, user);
 73         //提交插入的数据
 74         session.commit();
 75         session.close();
 76     }
 77      
 78     //根据 id 更新 user 表的数据
 79     @Test
 80     public void testUpdateUserById(){
 81         String statement = "user.updateUserById";
 82         //如果设置的 id不存在，那么数据库没有数据更改
 83         User user = new User();
 84         user.setId(4);
 85         user.setUsername("jim");
 86         session.update(statement, user);
 87         session.commit();
 88         session.close();
 89     }   
 91  
 92     //根据 id 删除 user 表的数据
 93     @Test
 94     public void testDeleteUserById(){
 95         String statement = "user.deleteUserById";
 96         session.delete(statement,4);
 97         session.commit();
 98         session.close();
 99     }
100 }

 1 package com.spring.model;
 2 
 3 import org.apache.ibatis.annotations.Delete;
 4 import org.apache.ibatis.annotations.Insert;
 5 import org.apache.ibatis.annotations.Select;
 6 import org.apache.ibatis.annotations.Update;
 7 
 8 public interface UserMapper {
 9 
10     //根据 id 查询 user 表数据
11     @Select("select * from user where id=#{id}")
12     public User selectUserById(int id) throws  Exception;
13 
14     //箱user插入一条数据
15     @Insert("insert into user(username,sex,birthday,address) values(#{username},#{sex},#{birthday},#{address})")
16     public void insertUser(User user) throws Exception;
17 
18     //根据 id 修改 user 表数据
19     @Update("update user set username=#{username},sex=#{sex} where id=#{id}")
20     public void updateUserById(User user) throws Exception;
21 
22     //根据 id 删除 user 表数据
23     @Delete("delete from user where id=#{id}")
24     public void deleteUserById(int id) throws Exception;
25 }

1 ......
2 <mappers>
3     <!-- xml方式，注册userMapper.xml文件，
4     userMapper.xml位于com.ys.mapper这个包下，所以resource写成com/ys/mapper/userMapper.xml
5     <mapper resource="mapping/userMapping.xml"/>-->
6     <mapper class="com.spring.model.UserMapper"></mapper>
7 </mappers>

 1 package com.spring;
 2 
 3 import com.spring.CRUDTest;
 4 import com.spring.model.User;
 5 import com.spring.model.UserMapper;
 6 import org.apache.ibatis.session.SqlSession;
 7 import org.apache.ibatis.session.SqlSessionFactory;
 8 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
 9 import org.junit.Before;
10 import org.junit.Test;
11 
12 import java.io.InputStream;
13 
14 public class TestAnnotationCRUD {
15     SqlSession session=null;
16 
17     @Before
18     public void init(){
19         //定义mybatis全局配置文件
20         String resource = "mybatis-configuration.xml";
21         //加载 mybatis 全局配置文件
22         InputStream inputStream = CRUDTest.class.getClassLoader().getResourceAsStream(resource);
23         //构建sqlSession的工厂
24         SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
25         //根据 sqlSessionFactory 产生 session
26         session = sessionFactory.openSession();
27     }
28 
29     //注解的增删改查方法测试
30     @Test
31     public void testAnncationCRUD() throws Exception {
32         //根据session获取 UserMapper接口
33         UserMapper userMapper = session.getMapper(UserMapper.class);
34         //调用selectUserById()方法
35         User user = userMapper.selectUserById(1);
36         System.out.println(user);
37 
38         //调用  insertUser() 方法
39         User user1 = new User();
40         user1.setUsername("aliks");
41         user1.setSex("不详");
42         userMapper.insertUser(user1);
43 
44         //调用 updateUserById() 方法
45         User user2 = new User();
46         user2.setId(6);
47         user2.setUsername("lbj");
48         userMapper.updateUserById(user2);
49 
50         //调用 () 方法
51         userMapper.deleteUserById(6);
52 
53         session.commit();
54         session.close();
55     }
56 
57 }