Mybatis 框架理解与快速入门详解代码与数据库

package com.yyl.mapper.impl; import com.yyl.bean.Student; import com.yyl.mapper.StudentMapper; import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import java.io.IOException; import java.io.InputStream; import java.util.List; /* 持久层实现类 */ public class StudentMapperImpl implements StudentMapper { /* 查询全部 */ @Override public List<Student> selectAll() { List<Student> list = null; SqlSession sqlSession = null; InputStream is = null; try{ //1.加载核心配置文件 is = Resources.getResourceAsStream("MyBatisConfig.xml"); //2.获取SqlSession工厂对象 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is); //3.通过工厂对象获取SqlSession对象 sqlSession = sqlSessionFactory.openSession(true); //4.执行映射配置文件中的sql语句，并接收结果 list = sqlSession.selectList("StudentMapper.selectAll"); } catch (Exception e) { e.printStackTrace(); } finally { //5.释放资源 if(sqlSession != null) { sqlSession.close(); } if(is != null) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } } //6.返回结果 return list; } /* 根据id查询 */ @Override public Student selectById(Integer id) { Student stu = null; SqlSession sqlSession = null; InputStream is = null; try{ //1.加载核心配置文件 is = Resources.getResourceAsStream("MyBatisConfig.xml"); //2.获取SqlSession工厂对象 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is); //3.通过工厂对象获取SqlSession对象 sqlSession = sqlSessionFactory.openSession(true); //4.执行映射配置文件中的sql语句，并接收结果 stu = sqlSession.selectOne("StudentMapper.selectById",id); } catch (Exception e) { e.printStackTrace(); } finally { //5.释放资源 if(sqlSession != null) { sqlSession.close(); } if(is != null) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } } //6.返回结果 return stu; } /* 新增功能 */ @Override public Integer insert(Student stu) { Integer result = null; SqlSession sqlSession = null; InputStream is = null; try{ //1.加载核心配置文件 is = Resources.getResourceAsStream("MyBatisConfig.xml"); //2.获取SqlSession工厂对象 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is); //3.通过工厂对象获取SqlSession对象 sqlSession = sqlSessionFactory.openSession(true); //4.执行映射配置文件中的sql语句，并接收结果 result = sqlSession.insert("StudentMapper.insert",stu); } catch (Exception e) { e.printStackTrace(); } finally { //5.释放资源 if(sqlSession != null) { sqlSession.close(); } if(is != null) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } } //6.返回结果 return result; } /* 修改功能 */ @Override public Integer update(Student stu) { Integer result = null; SqlSession sqlSession = null; InputStream is = null; try{ //1.加载核心配置文件 is = Resources.getResourceAsStream("MyBatisConfig.xml"); //2.获取SqlSession工厂对象 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is); //3.通过工厂对象获取SqlSession对象 sqlSession = sqlSessionFactory.openSession(true); //4.执行映射配置文件中的sql语句，并接收结果 result = sqlSession.update("StudentMapper.update",stu); } catch (Exception e) { e.printStackTrace(); } finally { //5.释放资源 if(sqlSession != null) { sqlSession.close(); } if(is != null) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } } //6.返回结果 return result; } /* 删除功能 */ @Override public Integer delete(Integer id) { Integer result = null; SqlSession sqlSession = null; InputStream is = null; try{ //1.加载核心配置文件 is = Resources.getResourceAsStream("MyBatisConfig.xml"); //2.获取SqlSession工厂对象 SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is); //3.通过工厂对象获取SqlSession对象 sqlSession = sqlSessionFactory.openSession(true); //4.执行映射配置文件中的sql语句，并接收结果 result = sqlSession.delete("StudentMapper.delete",id); } catch (Exception e) { e.printStackTrace(); } finally { //5.释放资源 if(sqlSession != null) { sqlSession.close(); } if(is != null) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } } //6.返回结果 return result; } }