简单java web学生信息管理系统

package com.dw.dao.impl; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.List; import com.dw.dao.StudentDao; import com.dw.model.Student; import com.dw.util.DbConn; public class StudentDaoImpl implements StudentDao { private Connection conn = DbConn.getConn(); public Student findStudentByid(int id) { Student stu = null; String sql = "select * from Student2 where stId=?"; try { PreparedStatement psmt = conn.prepareStatement(sql); psmt.setInt(1, id); ResultSet rs = psmt.executeQuery(); while (rs.next()) { int stId = rs.getInt("stId"); String stName = rs.getString("stName"); String stSex = rs.getString("stSex"); String stAge = rs.getString("stAge"); Long stTel = rs.getLong("stTel"); String stDept = rs.getString("stDept"); String stAddress = rs.getString("stAddress"); stu = new Student(stId, stName, stSex, stAge, stTel, stDept, stAddress); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return stu; } /** * ���ѧ����Ϣ * * @param stu * @retursn flag */ public boolean addStudent(Student stu) { // Student(stId,stName,stSex,stAge,stTel,stDept,stAddress) boolean flag = false; String sql = "insert into Student2(stId,stName,stSex,stAge,stTel,stDept,stAddress) values(?,?,?,?,?,?,?)"; try { PreparedStatement psmt = conn.prepareStatement(sql); psmt.setInt(1, stu.getStId()); psmt.setString(2, stu.getStName()); psmt.setString(3, stu.getStSex()); psmt.setString(4, stu.getStAge()); psmt.setLong(5, stu.getStTel()); psmt.setString(6, stu.getStDept()); psmt.setString(7, stu.getStAddress()); int i = psmt.executeUpdate(); if (i == 1) { flag = true; } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return flag; } /** * ɾ��ѧ����Ϣ * * @param id * @return flag */ public boolean delStudent(int id) { boolean flag = false; String sql = "delete from Student2 where stId=?"; try { PreparedStatement psmt = conn.prepareStatement(sql); psmt.setInt(1, id); if (psmt.executeUpdate() > 0) { flag = true; } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return flag; } /** * ����ѧ����Ϣ * * @param stu * @return flag */ public boolean updateStudent(Student stu) { boolean flag = false; String sql = "update Student2 set stName=?,stSex=?,stAge=?,stTel=?,stDept=?,stAddress=? where stId=? "; try { PreparedStatement psmt = conn.prepareStatement(sql); psmt.setString(1, stu.getStName()); psmt.setString(2, stu.getStSex()); psmt.setString(3, stu.getStAge()); psmt.setLong(4, stu.getStTel()); psmt.setString(5, stu.getStDept()); psmt.setString(6, stu.getStAddress()); psmt.setInt(7, stu.getStId()); int i = psmt.executeUpdate(); if (i == 1) { flag = true; } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return flag; } /** * ��ѯȫ��ѧ����Ϣ * * @return list */ @SuppressWarnings("unchecked") public List StSelect() { List list = new ArrayList(); String sql = "select * from Student2"; try { Statement smt = conn.createStatement(); ResultSet rs = smt.executeQuery(sql); // Student(stId,stName,stSex,stAge,stTel,stDept,stAddress) while (rs.next()) { int stId = rs.getInt("stId"); String stName = rs.getString("stName"); String stSex = rs.getString("stSex"); String stAge = rs.getString("stAge"); Long stTel = rs.getLong("stTel"); String stDept = rs.getString("stDept"); String stAddress = rs.getString("stAddress"); Student stu = new Student(stId, stName, stSex, stAge, stTel, stDept, stAddress); list.add(stu); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return list; } @Override public Student findStudentById(String id) { // TODO Auto-generated method stub Student student = null; String sql = "select * from Student2 where stId=?"; PreparedStatement pstmt; try { pstmt = conn.prepareStatement(sql); pstmt.setString(1, id); ResultSet rs = pstmt.executeQuery(); while (rs.next()) { student = new Student(); student.setStId(Integer.parseInt(rs.getString("stId"))); student.setStName(rs.getString("stName")); student.setStSex(rs.getString("stSex")); student.setStAge(rs.getString("stAge")); student.setStDept(rs.getString("stDept")); student.setStAddress(rs.getString("stAddress")); student.setStTel(Long.parseLong(rs.getString("stTel"))); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return student; } // public static void main(String[] args){ // StudentDaoImpl impl=new StudentDaoImpl(); // System.out.println(impl.findStudentById("1").toString()); // } }