Mybatis_映射文件

文章目录

1.映射文件

XxxMapper.xml

 PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
 "http://mybatis.org/dtd/mybatis-3-mapper.dtd">



      select * from tbl_employ where id = #{id}  
  
  
    insert into tbl_employ values (#{id}, #{last_name}, #{gender}, #{email})
  

  
    update tbl_employ set last_name = #{last_name} where id = #{id}
  

  
    delete from tbl_employ where id = #{id}
  

2.CRUD

    public SqlSessionFactory getSqlSessionFactory() throws IOException {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        return new SqlSessionFactoryBuilder().build(inputStream);
    }

1.select

test.java

    @Test
    public void test2()throws Exception{
        SqlSession sqlSession = getSqlSessionFactory().openSession();
        EmployMapperAnnocation mapper = sqlSession.getMapper(EmployMapperAnnocation.class);
        Employee byId = mapper.getById(1);
        System.out.println(byId);
        sqlSession.close();
    }

2.insert

test.java

    @Test
    public void test3()throws Exception{
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        //无参的话需要手动提交事务
        SqlSession openSession = sqlSessionFactory.openSession();

        EmployMapper mapper = openSession.getMapper(EmployMapper.class);

        Employee zjy = new Employee(null, "Zjy", "www.baidu.com", "0");

        mapper.addEmploy(zjy);

        openSession.commit();

        openSession.close();

    }

这里需要注意的是如果用工厂创建openSession无参的话,则需要手动提交commit,才可以生效

3.update

test.java

    @Test
    public void test4()throws Exception{
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        SqlSession openSession = sqlSessionFactory.openSession();
        EmployMapper mapper = openSession.getMapper(EmployMapper.class);
        mapper.updateEmploy(new Employee(1,"Zzz", "[e-mail]", "1"));
        openSession.commit();
        openSession.close();
    }

这里由于上面的映射文件改的只是last_name所以后面的没有修改

4.delete

test.java

    @Test
    public void test5()throws Exception{
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        SqlSession openSession = sqlSessionFactory.openSession();
        EmployMapper mapper = openSession.getMapper(EmployMapper.class);
        mapper.deleteEmploy(1);
        openSession.commit();
        openSession.close();
    }

5.获取自增的值

需要加上useGeneratedKeys属性和keyProperty的属性

    insert into tbl_employ values (#{id}, #{last_name}, #{gender}, #{email})
  

6.多个参数@Param注解

加上@Param()注解

7.多个参数map

还可以封装在一个map集合中,可以直接取值id,name,不用取param