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  • MyBatis的初始化方式

    1. 加载配置文件

        public static void main(String[] args) throws IOException {
            //mybatis的配置文件
            String resource = "conf.xml";
            //使用类加载器加载mybatis的配置文件(它也加载关联的映射文件)
            InputStream is = Test1.class.getClassLoader().getResourceAsStream(resource);
            //构建sqlSession的工厂
            SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(is);
            //使用MyBatis提供的Resources类加载mybatis的配置文件(它也加载关联的映射文件)
            //Reader reader = Resources.getResourceAsReader(resource); 
            //构建sqlSession的工厂
            //SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(reader);
            //创建能执行映射文件中sql的sqlSession
            SqlSession session = sessionFactory.openSession();
            /**
             * 映射sql的标识字符串,
             * me.gacl.mapping.userMapper是userMapper.xml文件中mapper标签的namespace属性的值,
             * getUser是select标签的id属性值,通过select标签的id属性值就可以找到要执行的SQL
             */
            String statement = "me.gacl.mapping.userMapper.getUser";//映射sql的标识字符串
            //执行查询返回一个唯一user对象的sql
            User user = session.selectOne(statement, 1);
            System.out.println(user);
        }

    详见: http://www.cnblogs.com/xdp-gacl/p/4261895.html

    2.扫描包

       public SqlSessionFactory SqlSessionFactory(){
            DataSource dataSource ;//数据库连接池,使用第三方即可
            TransactionFactory transactionFactory = new JdbcTransactionFactory();//事物,使用默认。也可以配合spring,使用spring自带的
            Environment environment = new Environment("development", transactionFactory, dataSource);//环境配置即 开发或者生产
            
            Configuration configuration = new Configuration(environment);//配置中心
            configuration.addMappers("conge.wang.sqlmappers");//加载mappers xml package,及扫描conge.wang.sqlmappers下面的xml配置
            //configuration.addMapper(TestSqlMapper.class);//或者加载mappers class。不过不推荐使用
            
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(configuration);//从SqlSessionFactoryBuilder构建
            
            return sqlSessionFactory;
        }

    详见:http://haoran-10.iteye.com/blog/2257417

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  • 原文地址:https://www.cnblogs.com/Gyoung/p/5124444.html
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