MyBatis

 

MyBatis工作流程：

1、通过Reader对象读取src目录下的mybatis.xml配置文件

2、通过SqlSessionFactoryBuilder对象创建SqlSessionFactory对象

3、从当前线程中获取SqlSession对象

4、事务开始，在mybatis中默认

5、通过SqlSession对象读取mapper.xml中的id，从而读取sql语句

6、事务提交,，在mybatis中默认

7、关闭SqlSession对象，并且分开当前线程与SqlSession对象，让GC尽早回收

 

//得到SqlSessionFactory 对象
private SqlSessionFactory getSqlSessionFactory(){
  if (sessionFactory == null) {
    String resource =  Play.configuration.getProperty("mybatis.configuration");     //得到mybatis.xml的地址
    
    Reader   reader = Resources.getResourceAsReader(resource);    //通过Reader读取配置文件
 
    Properties prop = new Properties();
    
    prop.put("url", Play.configuration.getProperty("db.mct.url"));
    prop.put("user", Play.configuration.getProperty("db.mct.user"));
    prop.put("pass", Play.configuration.getProperty("db.mct.pass"));
    prop.put("driver", Play.configuration.getProperty("db.mct.driver"));

    sessionFactory = new SqlSessionFactoryBuilder().build(reader, prop);   //通过SqlSessionFactoryBuilder对象创建SqlSessionFactory对象

  }
  
  return sessionFactory;
}

public List<String> getScreenShotPackageNames(Long taskId, String sn)  throws Exception {
        SqlSession sqlSession =  IbatisSessionFactoryMctDB.get().openSession();      //获取SqlSession对象
        try {
            DfxTaskMapper mapper =  sqlSession.getMapper(DfxTaskMapper.class);   //通过SqlSession对象读取DfxTaskMapper文件
            Map<String, Object> mmap = new HashMap<String, Object>();
            mmap.put("taskId",  taskId );
            mmap.put("sn",  sn );
          List<String> pkgNames= mapper.getScreenShotPackageNames(mmap);   //调用mapper中的方法
            return pkgNames;
        }catch (Exception e){
            throw e;
        }finally {
            if(null!=sqlSession){
                sqlSession.close();      //关闭sqlSession对象
            }
        }
    }
}

https://www.cnblogs.com/ysocean/tag/MyBatis%E8%AF%A6%E8%A7%A3%E7%B3%BB%E5%88%97/