JSP+SQL学生考勤管理系统(毕业设计)

package com.kaoqin.dao; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Vector; import com.kaoqin.db.Conn; import com.kaoqin.po.Teacher; public class TeacherDao { public static boolean login(Teacher th){ Conn db = new Conn(); String sqlstr = "select id,userName,userPass,course from teacher where userName='" + th.getUserName() + "'"; ResultSet rs = db.executeQuery(sqlstr); try { if (rs != null && rs.next()) { String pass = rs.getString("userPass"); if (th.getUserPass().equals(pass)) { th.setId(rs.getInt("id")); th.setCourse(rs.getString("course")); return true; } } } catch (SQLException ex) { } finally{ db.close(); } return false; } public static boolean addTeacher(Teacher t){ Conn db = new Conn(); String sqlstr = "insert into teacher(userName,userPass,tname,tsex,office,remark) values('" + t.getUserName() + "','" + t.getUserPass() + "','" + t.getTname() + "','" + t.getTsex() + "','" + t.getOffice() + "','" + t.getRemark() + "')"; System.out.println(sqlstr); boolean flag = false; if( db.executeUpdate(sqlstr) > 0) { flag = true; } db.close(); return flag; } public static Vector<Teacher> getTeachers(){ Vector<Teacher> rows = new Vector<Teacher>(); Conn db = new Conn(); String sqlstr = "select id,userName,userPass,tname,tsex,office,remark from teacher"; System.out.println(sqlstr); ResultSet rs = db.executeQuery(sqlstr); try { while(rs.next()) { // rs.getInt("id"); // rs.getString("userName"); // rs.getString("userPass"); // rs.getString("tname"); // rs.getString("tsex"); // rs.getString("office"); // rs.getString("remark"); Teacher t = new Teacher(rs.getInt("id"), rs.getString("userName"), rs.getString("userPass"), rs.getString("tname"), rs.getString("tsex"), rs.getString("office"), rs.getString("remark")); rows.add(t); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally{ try { rs.close(); rs = null; } catch (SQLException e) { } db.close(); } return rows; } public static Teacher getTeacherById(String id){ Conn conn = new Conn(); String sqlstr = "select id,userName,userPass,tname,tsex,office,remark from teacher where id=" + id; System.out.println(sqlstr); Teacher t = null; ResultSet rs = conn.executeQuery(sqlstr); try { if(rs.next()){ t = new Teacher(rs.getInt("id"), rs.getString("userName"), rs.getString("userPass"), rs.getString("tname"), rs.getString("tsex"), rs.getString("office"), rs.getString("remark")); } } catch (SQLException e) { e.printStackTrace(); } finally{ conn.close(); } return t; } public static boolean updateTeacher(Teacher t, String id){ Conn db = new Conn(); String sqlstr = "update teacher set userName='" + t.getUserName() + "',userPass='" + t.getUserPass() + "',tname='" + t.getTname() + "',tsex='" + t.getTsex() + "',office='" + t.getOffice() + "',remark='" + t.getRemark() + "' where id=" + id; System.out.println(sqlstr); boolean flag = false; if( db.executeUpdate(sqlstr) > 0) { flag = true; } db.close(); return flag; } public static boolean delTeacher(String id){ Conn db = new Conn(); String sqlstr = "delete from teacher where id=" + id; System.out.println(sqlstr); boolean flag = false; if( db.executeUpdate(sqlstr) > 0) { flag = true; } db.close(); return flag; } }