package loaderman;import java.io.IOException;import java.io.Reader;import java.sql.Connection;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;/** * 工具类 */public class MybatisUtil { private static ThreadLocal threadLocal = new ThreadLocal (); private static SqlSessionFactory sqlSessionFactory; /** * 加载位于src/mybatis.xml配置文件 */ static{ try { Reader reader = Resources.getResourceAsReader("mybatis.xml"); sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader); } catch (IOException e) { e.printStackTrace(); throw new RuntimeException(e); } } /** * 禁止外界通过new方法创建 */ private MybatisUtil(){} /** * 获取SqlSession */ public static SqlSession getSqlSession(){ //从当前线程中获取SqlSession对象 SqlSession sqlSession = threadLocal.get(); //如果SqlSession对象为空 if(sqlSession == null){ //在SqlSessionFactory非空的情况下，获取SqlSession对象 sqlSession = sqlSessionFactory.openSession(); //将SqlSession对象与当前线程绑定在一起 threadLocal.set(sqlSession); } //返回SqlSession对象 return sqlSession; } /** * 关闭SqlSession与当前线程分开 */ public static void closeSqlSession(){ //从当前线程中获取SqlSession对象 SqlSession sqlSession = threadLocal.get(); //如果SqlSession对象非空 if(sqlSession != null){ //关闭SqlSession对象 sqlSession.close(); //分开当前线程与SqlSession对象的关系，目的是让GC尽早回收 threadLocal.remove(); } } /** * 测试 */ public static void main(String[] args) { Connection conn = MybatisUtil.getSqlSession().getConnection(); System.out.println(conn!=null?"连接成功":"连接失败"); }} package loaderman;/** * 学生 */public class Student { private Integer id;//编号 private String name;//姓名 private Double sal;//薪水 public Student(){} public Student(Integer id, String name, Double sal) { this.id = id; this.name = name; this.sal = sal; } public Integer getId() { System.out.println("getId()"); return id; } public void setId(Integer id) { this.id = id; } public String getName() { System.out.println("getName()"); return name; } public void setName(String name) { this.name = name; } public Double getSal() { System.out.println("getSal()"); return sal; } public void setSal(Double sal) { this.sal = sal; }} package loaderman;import java.util.List;import org.apache.ibatis.session.SqlSession;/** * 持久层 * @author AdminTC */public class StudentDao1 { /** * 增加学生 */ public void add(Student student) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.insert("loaderman.Student.add",student); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } /** * 根据ID查询学生 */ public Student findById(int id) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); Student student = sqlSession.selectOne("loaderman.Student.findById",id); sqlSession.commit(); return student; }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } /** * 查询所有学生 */ public List findAll() throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); return sqlSession.selectList("loaderman.Student.findAll"); }catch(Exception e){ e.printStackTrace(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } /** * 更新学生 */ public void update(Student student) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.update("loaderman.Student.update",student); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } /** * 删除学生 */ public void delete(Student student) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.delete(Student.class.getName()+".delete",student); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } public static void main(String[] args) throws Exception{ StudentDao1 dao = new StudentDao1();// dao.add(new Student(1,"哈哈",7000D));// dao.add(new Student(2,"呵呵",8000D));// dao.add(new Student(3,"班长",9000D));// dao.add(new Student(4,"键状高",10000D));// Student student = dao.findById(4); List studentList = dao.findAll(); for(Student student : studentList){ System.out.print(student.getId()+":"+student.getName()+":"+student.getSal()); System.out.println(); } //Student student = dao.findById(3); //student.setName("靓班长"); //dao.update(student);// Student student = dao.findById(3);// System.out.print(student.getId()+":"+student.getName()+":"+student.getSal()); //dao.delete(student); }} package loaderman;import org.apache.ibatis.session.SqlSession;/** * 持久层 */public class StudentDao2 { /** * 增加学生 */ public void add(Student student) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); sqlSession.insert("loaderman.Student.add",student); sqlSession.commit(); }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } /** * 根据ID查询学生 */ public Student findById(int id) throws Exception{ SqlSession sqlSession = null; try{ sqlSession = MybatisUtil.getSqlSession(); Student student = sqlSession.selectOne("loaderman.Student.findById",id); sqlSession.commit(); return student; }catch(Exception e){ e.printStackTrace(); sqlSession.rollback(); throw e; }finally{ MybatisUtil.closeSqlSession(); } } public static void main(String[] args) throws Exception{ StudentDao2 dao = new StudentDao2(); //dao.add(new Student(1,"班长",7000D)); Student student = dao.findById(1); if(student == null){ System.out.println("YES"); } System.out.println(student.getId()+":"+student.getName()+":"+student.getSal()); }} insert into students(id,name,sal) values(#{id},#{name},#{sal}) update students set name=#{name},sal=#{sal} where id=#{id} delete from students where id = #{id}
insert into students(students_id,students_name,students_sal) values(#{id},#{name},#{sal})
db.properties
mysql.driver=com.mysql.jdbc.Drivermysql.url=jdbc:mysql://127.0.0.1:3306/loadermanmysql.username=rootmysql.password=rootoracle.driver=oracle.jdbc.driver.OracleDriveroracle.url=jdbc:oracle:thin:@127.0.0.1:1521:orcloracle.username=scottoracle.password=tiger