y2myBatis

映射配置文件

 

  
  
  
  
    
    
     
     
       
         
             
            
            
            
            
            
            
             
               
                
                 
                 
            
         
     
     
 
7）创建方法接口UserMapper.java和定义操作t_user表的sql映射文件UserMapper.xml

 
  
  
    
    
   
   
    
    
         
         
         
   
    
    
    
      
         
             
             
             
             
             
             
             
             
                 
                 
                 
                 
             
         
      
     
     
     
         
         
         
     
 
建立一个工具类文件

 
 import java.io.Reader;
  
  import org.apache.ibatis.io.Resources;
  import org.apache.ibatis.session.SqlSession;
 import org.apache.ibatis.session.SqlSessionFactory;
 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
 
 public class DBTools {
     public static SqlSessionFactory sessionFactory;
     
     static{
         try {
             //使用MyBatis提供的Resources类加载mybatis的配置文件
             Reader reader = Resources.getResourceAsReader("mybatis.cfg.xml");
             //构建sqlSession的工厂
             sessionFactory = new SqlSessionFactoryBuilder().build(reader);
         } catch (Exception e) {
             e.printStackTrace();
         }
         
     }
     //创建能执行映射文件中sql的sqlSession
     public static SqlSession getSession(){
         return sessionFactory.openSession();
     }
     
 }
测试

public class UserService {
 
    
      
     public static void main(String[] args) {
           insertUser();
//        deleteUser();
 //        selectUserById();
 //        selectAllUser();
     }

     
     /**
      * 新增用户
      */
     private static void insertUser() {
         SqlSession session = DBTools.getSession();
         UserMapper mapper = session.getMapper(UserMapper.class);
         UserBean user = new UserBean("懿", "1314520", 7000.0);
         try {
             mapper.insertUser(user);
           System.out.println(user.toString());
              session.commit();
         } catch (Exception e) {
             e.printStackTrace();
            session.rollback();
         }
     }
     
     
     /**
     * 删除用户
      */
     private static void deleteUser(){
         SqlSession session=DBTools.getSession();
         UserMapper mapper=session.getMapper(UserMapper.class);
         try {
             mapper.deleteUser(1);
             session.commit();
         } catch (Exception e) {
             e.printStackTrace();
            session.rollback();
         }
     }
    
     
     /**
      * 根据id查询用户
      */
     private static void selectUserById(){
         SqlSession session=DBTools.getSession();
         UserMapper mapper=session.getMapper(UserMapper.class);
         try {
         UserBean user=    mapper.selectUserById(2);
        System.out.println(user.toString());
             
             session.commit();
         } catch (Exception e) {
             e.printStackTrace();
             session.rollback();
         }
     }
     
     /**
      * 查询所有的用户
      */
     private static void selectAllUser(){
         SqlSession session=DBTools.getSession();
         UserMapper mapper=session.getMapper(UserMapper.class);
         try {
         List user=mapper.selectAllUser();
         System.out.println(user.toString());
         session.commit();
         } catch (Exception e) {
             e.printStackTrace();
             session.rollback();
        }
     }
    
 
}