学生信息管理系统初始版.zip

package com.yujian.dao; import com.yujian.model.ClassInfo; import com.yujian.model.Student; import com.yujian.util.DBHelper; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Timestamp; import java.util.ArrayList; import java.util.Date; import java.util.List; public class StudentDao { private DBHelper db=new DBHelper(); public void insertStudent(Student student){ String sql="insert into student values(null,?,?,?,?)"; try { PreparedStatement pst=db.getConnection().prepareStatement(sql); pst.setString(1,student.getStuName()); pst.setInt(2,student.getStuSex()); pst.setTimestamp(3,new Timestamp(student.getBirth().getTime())); pst.setInt(4,student.getClassInfo().getCid()); pst.execute(); } catch (SQLException e) { e.printStackTrace(); } finally { db.closeConn(); } } public void updateStudent(Student student){ String sql="update student set stu_name=?,stu_sex=?,stu_birth=?,cid=? where stu_id=?"; try { PreparedStatement pst=db.getConnection().prepareStatement(sql); pst.setString(1,student.getStuName()); pst.setInt(2,student.getStuSex()); pst.setTimestamp(3,new Timestamp(student.getBirth().getTime())); pst.setInt(4,student.getClassInfo().getCid()); pst.setInt(5,student.getStuId()); pst.execute(); } catch (SQLException e) { e.printStackTrace(); } finally { db.closeConn(); } } public void deleteStudent(int stuId){ String sql="delete from student where stu_id=?"; try { PreparedStatement pst=db.getConnection().prepareStatement(sql); pst.setInt(1,stuId); pst.execute(); } catch (SQLException e) { e.printStackTrace(); } finally { db.closeConn(); } } public List<Student> findStudentAll(){ //数据库后连接断开之后，是不能通过ResultSet去获得数据值得 //所以要转换到list集合里面去，这样哪怕数据库连接关闭，我可以在内存里 // 操作 list集合 List<Student> list=new ArrayList<Student>(); String sql="select s.stu_id,s.stu_name,s.stu_sex,s.stu_birth,s.cid,c.cname"; sql+=" from student s INNER JOIN classinfo c on s.cid=c.cid;"; try { PreparedStatement pst = db.getConnection().prepareStatement(sql); ResultSet rs = pst.executeQuery(); //获取记录集需要迭代 while (rs.next()) { //循环一次就取一行 int stuId = rs.getInt("stu_id"); String stuName = rs.getString("stu_name"); int stuSex=rs.getInt("stu_sex"); Date stuBirth=rs.getDate("stu_birth"); Student s=new Student(); s.setStuId(stuId); s.setStuName(stuName); s.setStuSex(stuSex); s.setBirth(stuBirth); ClassInfo c=new ClassInfo(); c.setCid(rs.getInt("cid")); c.setCname(rs.getString("cname")); s.setClassInfo(c); list.add(s); } }catch (Exception e){ e.printStackTrace(); }finally { db.closeConn(); } return list; } public Student findStudentById(int paramStuId){ Student student=null; String sql="select s.stu_id,s.stu_name,s.stu_sex,s.stu_birth,s.cid,c.cname"; sql+=" from student s INNER JOIN classinfo c on s.cid=c.cid"; sql+=" where s.stu_id=?"; try { PreparedStatement pst = db.getConnection().prepareStatement(sql); pst.setInt(1,paramStuId); ResultSet rs = pst.executeQuery(); //获取记录集需要迭代 while (rs.next()) { //循环一次就取一行 int stuId = rs.getInt("stu_id"); String stuName = rs.getString("stu_name"); int stuSex=rs.getInt("stu_sex"); Date stuBirth=rs.getDate("stu_birth"); student=new Student(); student.setStuId(stuId); student.setStuName(stuName); student.setStuSex(stuSex); student.setBirth(stuBirth); ClassInfo c=new ClassInfo(); c.setCid(rs.getInt("cid")); c.setCname(rs.getString("cname")); student.setClassInfo(c); } }catch (Exception e){ e.printStackTrace(); }finally { db.closeConn(); } return student; } }