基于JSP+Servlet+Mysql的学生信息管理系统(高分期末大作业)

package com.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import com.bean.StudentBean; import com.util.DBUtil; public class StudentDao { // 添加 public static boolean addStudent(String sid, String sname, String scls, String age, String major) { Connection conn = DBUtil.getConnectDb(); String sql = "INSERT INTO stus VALUES(?,?,?,?,?)"; int rs; PreparedStatement stm = null; try { stm = conn.prepareStatement(sql); stm.setString(1, sid); stm.setString(2, sname); stm.setString(3, scls); stm.setString(4, age); stm.setString(5, major); boolean a = false; rs = stm.executeUpdate(); if (rs == 1) { return true; } else { return false; } } catch (SQLException e) { // TODO: handle exception e.printStackTrace(); return false; } } // 更改 public static boolean updateStudent(String sid, String sname, String scls, String age, String major) { Connection conn = DBUtil.getConnectDb(); String sql = "UPDATE stus SET sname=?,scls=?,age=?,major=? WHERE sid=?"; int rs; PreparedStatement stm = null; try { stm = conn.prepareStatement(sql); stm.setString(1, sname); stm.setString(2, scls); stm.setString(3, age); stm.setString(4, major); stm.setString(5, sid); boolean a = false; rs = stm.executeUpdate(); if (rs == 1) { return true; } else { return false; } } catch (SQLException e) { // TODO: handle exception e.printStackTrace(); return false; } } // 删除 public static boolean deleteStudent(String sid) { Connection conn = DBUtil.getConnectDb(); String sql = "DELETE FROM stus WHERE sid=?"; int rs; PreparedStatement stm = null; try { stm = conn.prepareStatement(sql); stm.setString(1, sid); boolean a = false; rs = stm.executeUpdate(); if (rs == 1) { return true; } else { return false; } } catch (SQLException e) { // TODO: handle exception e.printStackTrace(); return false; } } // 查询所有信息 public static List<StudentBean> getList() { List<StudentBean> studentArray = new ArrayList<StudentBean>(); // ArrayList studentArray = new ArrayList(); Connection conn = DBUtil.getConnectDb(); String sql = "SELECT * FROM stus"; PreparedStatement stm = null; ResultSet rs = null; try { stm = conn.prepareStatement(sql); rs = stm.executeQuery(); while (rs.next()) { StudentBean m = new StudentBean(); m.setSid(rs.getString("sid")); m.setSname(rs.getString("sname")); m.setScls(rs.getString("scls")); m.setAge(rs.getString("age")); m.setMajor(rs.getString("major")); studentArray.add(m); } rs.close(); stm.close(); return studentArray; } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } // 根据学号查询单个学生信息 public static ArrayList getList(String sid) { ArrayList studentArray = new ArrayList(); // 建立一个数组集合 Connection conn = DBUtil.getConnectDb(); String sql = "SELECT * FROM stus WHERE sid=?"; PreparedStatement stm = null; ResultSet rs = null; try { stm = conn.prepareStatement(sql); stm.setString(1, sid); rs = stm.executeQuery(); while (rs.next()) { StudentBean m = new StudentBean(); m.setSid(rs.getString("sid")); m.setSname(rs.getString("sname")); m.setScls(rs.getString("scls")); m.setAge(rs.getString("age")); m.setMajor(rs.getString("major")); studentArray.add(m); } rs.close(); stm.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return studentArray; } //批量删除 public void piLiangDelete(String ids) { // TODO Auto-generated method stub Connection conn = DBUtil.getConnectDb(); String sql = "DELETE FROM stus WHERE sid in ("+ids+")"; PreparedStatement stm = null; try { stm = conn.prepareStatement(sql); stm.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }