一、MyBatis核心配置文件mybatis-config.xml

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二、映射文件×××Mapper.xml

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       5     
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       8         select * from customer where id = #{id} 9     10     
      12         select * from customer where username like concat('%',#{value},'%');13     14     
      16         select * from customer17     18     
      19     
      
       21         insert into customer(username,jobs,phone)22         values(#{username},#{jobs},#{phone})23     
      24     
      25     
      
       26         
       
        27             select last_insert_id()28         
       29         insert into customer(id,username,jobs,phone)30         values(#{id},#{username},#{jobs},#{phone})31     
      32     
      33     
      
       34         update customer set35         username=#{username},jobs=#{jobs},phone=#{phone}36         where id=#{id}37     
      38     
      39     
      
       40         delete from customer where id=#{id}41     
      42 
     

三、MyBatis工作原理

1 //1.读取配置文件 2 String resource = "mybatis-config.xml"; 3 InputStream inputStream = Resources.getResourceAsStream(resource); 4 //2.根据配置文件构建SqlSessionFactory 5 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); 6 //3.通过SqlSessionFactory创建SqlSession 7 SqlSession sqlSession = sqlSessionFactory.openSession(); 8 //4.SqlSession执行映射文件中定义的SQL语句，并返回映射结果 9 //即：调用映射文件中不同的子元素id,执行相应的操作10 {11          Customer customer = sqlSession.selectOne("com.itheima.mapper"12                     + “.CustomerMapper.findCustomerById”, 1);          13 }         14 //5.关闭SqlSession15 sqlSession.close();

log4j.properties日志文件：

log4j.rootLogger=ERROR, stdout

log4j.logger.com.wxy=DEBUG

log4j.appender.stdout=org.apache.log4j.ConsoleAppender

log4j.appender.stdout.layout=org.apache.log4j.PatternLayout

log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n