基于JavaWeb实现学生选课系统

package com.xuanke.servlet; import java.io.IOException; import java.sql.Connection; import java.util.ArrayList; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import com.xuanke.dao.CourseDao; import com.xuanke.dao.StudentCourseDao; import com.xuanke.dao.StudentDao; import com.xuanke.model.Course; import com.xuanke.model.PageBean; import com.xuanke.model.Student; import com.xuanke.model.StudentCourse; import com.xuanke.model.User; import com.xuanke.util.DbUtil; import com.xuanke.util.PageUtil; import com.xuanke.util.ResponseUtil; import com.xuanke.util.StringUtil; import net.sf.json.JSONObject; /** * 学生Servlet类 * @author Administrator * */ public class StudentServlet extends HttpServlet { /** * */ private static final long serialVersionUID = 1L; private DbUtil dbUtil=new DbUtil(); private StudentDao studentDao=new StudentDao(); private StudentCourseDao studentCourseDao=new StudentCourseDao(); private CourseDao courseDao=new CourseDao(); @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); String action=request.getParameter("action"); if("list".equals(action)){ this.list(request, response); }else if("preSave".equals(action)){ this.preSave(request, response); }else if("save".equals(action)){ this.save(request, response); }else if("delete".equals(action)){ this.delete(request, response); }else if("courseList".equals(action)){ this.courseList(request, response); }else if("showInfo".equals(action)){ this.showInfo(request,response); }else if("showScore".equals(action)){ this.showScore(request,response); }else if("preSelect".equals(action)){ this.preSelect(request,response); }else if("selectCourse".equals(action)){ this.selectCourse(request,response); }else if("unSelectCourse".equals(action)){ this.unSelectCourse(request, response); } } /** * 显示数据 * @param request * @param response * @throws ServletException * @throws IOException */ private void list(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { HttpSession session=request.getSession(); String page=request.getParameter("page"); String s_userName=request.getParameter("s_userName"); Student s_student=new Student(); if(StringUtil.isEmpty(page)){ page="1"; s_student.setUserName(s_userName); session.setAttribute("s_student", s_student); }else{ s_student=(Student) session.getAttribute("s_student"); } PageBean pageBean=new PageBean(Integer.parseInt(page),3); Connection con=null; try{ con=dbUtil.getCon(); List<Student> studentList=studentDao.studentList(con, pageBean, s_student); int total=studentDao.studentCount(con, s_student); String pageCode=PageUtil.getPagation(request.getContextPath()+"/student?action=list", total, Integer.parseInt(page), 3); request.setAttribute("pageCode", pageCode); request.setAttribute("modeName", "学生信息管理"); request.setAttribute("studentList", studentList); request.setAttribute("mainPage", "student/list.jsp"); request.getRequestDispatcher("main.jsp").forward(request, response); }catch(Exception e){ e.printStackTrace(); }finally{ try { dbUtil.closeCon(con); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } /** * 添加修改预操作 * @param request * @param response * @throws ServletException * @throws IOException */ private void preSave(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { String id=request.getParameter("id"); if(StringUtil.isNotEmpty(id)){ request.setAttribute("actionName", "学生信息修改"); Connection con=null; try{ con=dbUtil.getCon(); Student student=studentDao.loadStudentById(con, id); request.setAttribute("student", student); }catch(Exception e){ e.printStackTrace(); }finally{ try { dbUtil.closeCon(con); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } }else{ request.setAttribute("actionName", "学生信息添加"); } request.setAttribute("mainPage", "student/save.jsp"); request.setAttribute("modeName", "学生信息管理"); request.getRequestDispatcher("main.jsp").forward(request, response); } /** * 添加修改操作 * @param request * @param response * @throws ServletException * @throws IOException */ private void save(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { String id=request.getParameter("id"); String userName=request.getParameter("userName"); String password=request.getParameter("password"); String trueName=request.getParameter("trueName"); String stuNo=request.getParameter("stuNo"); String professional=request.getParameter("professional"); Student student=new Student(userName,password,trueName,stuNo,professional); Connection con=null; try{ con=dbUtil.getCon(); if(StringUtil.isNotEmpty(id)){ // 修改 student.setId(Integer.parseInt(id)); studentDao.studentUpdate(con, student); }else{ studentDao.studentAdd(con, student); } response.sendRedirect("student?action=list"); }catch(Exception e){ e.printStackTrace(); }finally{ try { dbUtil.closeCon(con); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } /** * 删除操作 * @param request * @param response * @throws ServletException * @throws IOException */ private void delete(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { String id=request.getParameter("id"); Connection con=null; try{ con=dbUtil.getCon(); JSONObject result = new JSONObject(); if(studentCourseDao.existStudentByStuId(con, id)){ result.put("success", false); }else{ studentDao.studentDelete(con, id); result.put("success", true); } ResponseUtil.write(result, response); }catch(Exception e){ e.printStackTrace(); }finally{ try { dbUtil.closeCon(con); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } /** * 查询学生的课程 * @param request * @param response * @throws ServletException * @throws IOException */ private void courseList(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { HttpSession session=request.getSession(); User currentUser=(User) session.getAttribute("currentUser"); Connection con=null; try{ con=dbUtil.getCon(); List<StudentCourse> courseList=studentCourseDao.findCourseByStudentId(con, currentUser.getUserId()); request.setAttribute("courseList", courseList); request.setAttribute("modeName", "查看课程信息"); request.setAttribute("mainPage", "student/courseList.jsp"); request.getRequestDispatcher("main.jsp").forward(request, response); }catch(Exception e){ e.printStackTrace(); }finally{ try { dbUtil.closeCon(con); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } /** * 查看个人信息 * @param request * @param response * @throws ServletException * @throws IOException */