Java怎样实现在线选课系统，相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。
一、项目简述
功能： 系统分为三个角色。最高权限管理员，学生，教师，包括 学生管理，教师管理，课程管理，选课，退课，成绩查 询。，教学课程，查看选课名单等等功能完全齐备。
二、项目运行
环境配置： Jdk1.8 + Tomcat8.5 + Mysql + Eclispe (IntelliJ IDEA,Eclispe,MyEclispe,Sts 都支持)
项目技术： JSP +Spring + SpringMVC + MyBatis + Bootstrap4+ css + JavaScript + JQuery + Ajax + particles.js+ maven等等。
用户管理控制器:
@RequestMapping("/user/")@Controllerpublic class UserController { @Autowired private IUserService userService; @Autowired private IRoleService roleService; @Resource private ProcessEngineConfiguration configuration; @Resource private ProcessEngine engine; @GetMapping("/index") @ApiOperation("跳转用户页接口") @PreAuthorize("hasRole('管理员')") public String index(String menuid,Model model){ List<Role> roles = queryAllRole(); model.addAttribute("roles",roles); model.addAttribute("menuid",menuid); //用户首页 return "views/user/user_list"; } @GetMapping("/listpage") @ApiOperation("查询用户分页数据接口") @ApiImplicitParams({ @ApiImplicitParam(name = "UserQuery", value = "用户查询对象", defaultValue = "userQuery对象") }) @ResponseBody @PreAuthorize("hasRole('管理员')") public PageList listpage(UserQuery userQuery){ return userService.listpage(userQuery); } //添加用户 @PostMapping("/addUser") @ApiOperation("添加用户接口") @ResponseBody public Map<String,Object> addUser(User user){ Map<String, Object> ret = new HashMap<>(); ret.put("code",-1); if(StringUtils.isEmpty(user.getUsername())){ ret.put("msg","请填写用户名"); return ret; } if(StringUtils.isEmpty(user.getPassword())){ ret.put("msg","请填写密码"); return ret; } if(StringUtils.isEmpty(user.getEmail())){ ret.put("msg","请填写邮箱"); return ret; } if(StringUtils.isEmpty(user.getTel())){ ret.put("msg","请填写手机号"); return ret; } if(StringUtils.isEmpty(user.getHeadImg())){ ret.put("msg","请上传头像"); return ret; } if(userService.addUser(user)<=0) { ret.put("msg", "添加用户失败"); return ret; } ret.put("code",0); ret.put("msg","添加用户成功"); return ret; } @PostMapping("/editSaveUser") @ApiOperation("修改用户接口") @PreAuthorize("hasRole('管理员')") @ResponseBody public Message editSaveUser(User user){ if(StringUtils.isEmpty(user.getUsername())){ return Message.error("请填写用户名"); } if(StringUtils.isEmpty(user.getEmail())){ return Message.error("请填写邮箱"); } if(StringUtils.isEmpty(user.getTel())){ return Message.error("请填写手机号"); } try { userService.editSaveUser(user); return Message.success(); } catch (Exception e) { e.printStackTrace(); return Message.error("修改用户信息失败"); } } //添加用户 @GetMapping("/deleteUser") @ApiOperation("删除用户接口") @ApiImplicitParams({ @ApiImplicitParam(name = "id", value = "如:88",required = true) }) @PreAuthorize("hasRole('管理员')") @ResponseBody public AjaxResult deleteUser(@RequestParam(required = true) Long id){ AjaxResult ajaxResult = new AjaxResult(); try { userService.deleteUser(id); } catch (Exception e) { e.printStackTrace(); return new AjaxResult("删除失败"); } return ajaxResult; } @PostMapping(value="/deleteBatchUser") @ApiOperation("批量删除用户接口") @PreAuthorize("hasRole('管理员')") @ResponseBody public AjaxResult deleteBatchUser(String ids){ String[] idsArr = ids.split(","); List list = new ArrayList(); for(int i=0;i<idsArr.length;i++){ list.add(idsArr[i]); } try{ userService.batchRemove(list); return new AjaxResult(); }catch(Exception e){ return new AjaxResult("批量删除失败"); } } //查询所有角色 public List<Role> queryAllRole(){ return roleService.queryAll(); } //添加用户的角色 @PostMapping("/addUserRole") @ApiOperation("添加用户角色接口") @ApiImplicitParams({ @ApiImplicitParam(name = "paramMap", value = "如:{userId:1,[1,2,3,4]]}") }) @ResponseBody public AjaxResult addUserRole(@RequestBody Map paramMap){ AjaxResult ajaxResult = new AjaxResult(); String userId = (String)paramMap.get("userId"); List roleIds = (List) paramMap.get("roleIds"); try { //添加用户对应的角色 roleService.addUserRole(userId,roleIds); return ajaxResult; }catch (Exception e){ e.printStackTrace(); return new AjaxResult("保存角色失败"); } } //添加用户 @RequestMapping("/regSaveUser") @ResponseBody public Long addTeacher(User user){ System.out.println("保存用户...."+user); userService.addUser(user); //保存工作流程操作 IdentityService is = engine.getIdentityService(); // 添加用户组 org.activiti.engine.identity.User userInfo = userService.saveUser(is, user.getUsername()); // 添加用户对应的组关系 Group stuGroup = new GroupEntityImpl(); stuGroup.setId("stuGroup"); Group tGroup = new GroupEntityImpl(); tGroup.setId("tGroup"); if(user.getType() == 2) { //保存老师组 userService.saveRel(is, userInfo, tGroup); } if(user.getType() == 3) { //保存学生组 userService.saveRel(is, userInfo, stuGroup); } Long userId = user.getId(); return userId; } @RequestMapping(value="/update_pwd",method=RequestMethod.GET) public String updatePwd(){ return "views/user/update_pwd"; } @ResponseBody @PostMapping("/update_pwd") public Message updatePassword(@RequestParam(name="oldPwd",required=true)String oldPwd, @RequestParam(name="newPwd",required=true)String newPwd){ String username = CommonUtils.getLoginUser().getUsername(); User userByUserName = userService.findUserByUserName(username); if(userByUserName!=null){ String password = userByUserName.getPassword(); BCryptPasswordEncoder bCryptPasswordEncoder = new BCryptPasswordEncoder(); boolean matches = bCryptPasswordEncoder.matches(oldPwd, password); if(!matches){ return Message.error("旧密码不正确");//true } userByUserName.setPassword(bCryptPasswordEncoder.encode(newPwd)); if(userService.editUserPassword(userByUserName)<=0){ return Message.error("密码修改失败"); } } return Message.success(); } @ResponseBody @PostMapping("/clear_cache") public Message clearCache(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setHeader("Cache-Control","no-store"); response.setHeader("Pragrma","no-cache"); response.setDateHeader("Expires",0); return Message.success(); }}角色控制器：
@Controllerpublic class RoleController { @Autowired private IRoleService roleService; @Autowired private IPermissionService permissionService; @PreAuthorize("hasRole('管理员')") @ResponseBody @RequestMapping("/role/doAdd") public String doAdd(Role role){ //角色添加 return "ok"; } //添加角色 @RequestMapping("/role/addRole") @PreAuthorize("hasRole('管理员')") @ResponseBody public AjaxResult addRole(Role role){ System.out.println("保存角色...."+role); try { roleService.saveRole(role); return new AjaxResult(); } catch (Exception e) { e.printStackTrace(); return new AjaxResult("操作失败"); } } @PreAuthorize("hasRole('管理员')") @RequestMapping("/role/index") public String index(Model model){ List<Permission> permisisons = permissionService.findAllPermisisons(); model.addAttribute("permissions",permisisons); //返回角色 return "views/role/role_list"; } @RequestMapping("/role/listpage") @ResponseBody public PageList listpage(RoleQuery roleQuery){ System.out.println("传递参数:"+roleQuery); return roleService.listpage(roleQuery); } //修改用户editSaveUser @RequestMapping("/role/editSaveRole") @ResponseBody public AjaxResult editSaveRole(Role role){ System.out.println("修改角色...."+role); try { roleService.editSaveRole(role); return new AjaxResult(); } catch (Exception e) { e.printStackTrace(); } return new AjaxResult("修改失败"); } //添加角色 @RequestMapping("/role/deleteRole") @ResponseBody public AjaxResult deleteRole(Long id){ System.out.println("删除角色...."+id); AjaxResult ajaxResult = new AjaxResult(); try { roleService.deleteRole(id); } catch (Exception e) { e.printStackTrace(); return new AjaxResult("删除失败"); } return ajaxResult; } //添加角色权限 addRolePermission @RequestMapping("/role/addRolePermission") @ResponseBody public AjaxResult addRolePermission(@RequestBody Map paramMap){ AjaxResult ajaxResult = new AjaxResult(); String roleId = (String)paramMap.get("roleId"); List permissionIds = (List) paramMap.get("permissionIds"); try { //添加角色对应的权限 roleService.addRolePermission(roleId,permissionIds); return ajaxResult; }catch (Exception e){ e.printStackTrace(); return new AjaxResult("保存权限失败"); } } }学生控制器：
@RequestMapping("/student")@Controller@Api(tags = "学生管理接口")public class StudentController { @Autowired private IUserService userService; @Autowired private ICourseService courseService; @Autowired private IClassesService classesService; @Resource private ProcessEngine engine; @Autowired private IOperaterLogService operaterLogService; //老师列表 //后台查询学生列表 @RequestMapping("/index") public String index(Model model){ //用户首页 model.addAttribute("courses",courseService.queryAll()); model.addAttribute("classes",classesService.queryAll()); return "views/student/student_list"; } @RequestMapping("/listpage") @ResponseBody public PageList listpage(UserQuery userQuery){ userQuery.setType(3L);//2表示老学生 return userService.listpage(userQuery); } @PostMapping("/addSaveStu") @ApiOperation("添加学生接口") @PreAuthorize("hasRole('管理员')") @ResponseBody public Message addSaveStudent(User user){ if(StringUtils.isEmpty(user.getUsername())){ return Message.error("请填写用户名"); } if(StringUtils.isEmpty(user.getPassword())){ return Message.error("请填写密码"); } if(StringUtils.isEmpty(user.getEmail())){ return Message.error("请填写邮箱"); } if(StringUtils.isEmpty(user.getTel())){ return Message.error("请填写手机号"); } if(StringUtils.isEmpty(user.getStunum())){ return Message.error("请填写学号"); } User userByUserName = userService.findUserByUserName(user.getUsername()); if(userByUserName!=null){ return Message.error("用户名已存在"); } if(userService.findByStuNum(user.getStunum())!=null){ return Message.error("该学号已存在"); } user.setType(3); if(userService.addUser(user)<=0){ return Message.error("学生添加失败"); } //保存工作流程操作 IdentityService is = engine.getIdentityService(); // 添加用户组 org.activiti.engine.identity.User userInfo = userService.saveUser(is, user.getUsername()); // 添加用户对应的组关系 Group stuGroup = new GroupEntityImpl(); stuGroup.setId("stuGroup"); userService.saveRel(is, userInfo, stuGroup); operaterLogService.add("添加学生成功,学生名称:"+user.getUsername()); return Message.success(); } //修改用户editSaveUser @PostMapping("/editSaveStu") @ApiOperation("修改学生接口") @PreAuthorize("hasRole('管理员')") @ResponseBody public Message editSaveStu(User user){ if(StringUtils.isEmpty(user.getUsername())){ return Message.error("请填写用户名"); } if(StringUtils.isEmpty(user.getEmail())){ return Message.error("请填写邮箱"); } if(StringUtils.isEmpty(user.getTel())){ return Message.error("请填写手机号"); } User userByUserName = userService.findUserByUserName(user.getUsername()); if(userByUserName!=null){ if(!userByUserName.getId().equals(user.getId())){ return Message.error("该用户名已存在"); } } try { userService.editSaveUser(user); operaterLogService.add("编辑学生成功,学生名称:"+user.getUsername()); return Message.success(); } catch (Exception e) { e.printStackTrace(); return Message.error("学生编辑失败"); } } //editSaveStuXk @PostMapping("/editSaveStuXk") @ApiOperation("修改用户接口") @ApiImplicitParams({ @ApiImplicitParam(name = "User", value = "学生选课") }) @ResponseBody public AjaxResult editSaveStuXk(User user){ try { userService.editSaveXk(user); operaterLogService.add("修改学生选课成功,学生名称:"+user.getUsername()); return new AjaxResult(); } catch (Exception e) { e.printStackTrace(); } return new AjaxResult("修改失败"); } }教师管理控制器：
@RequestMapping("/teacher")@Controller@Api(tags = "教师管理接口")public class TeacherController { @Autowired private IUserService userService; @Autowired private IClassesService classesService; @Resource private ProcessEngine engine; @Autowired private IOperaterLogService operaterLogService; //老师列表 @RequestMapping("/index") public String index(Model model){ //用户首页 model.addAttribute("classes",classesService.queryAll()); return "views/teacher/teacher_list"; } @RequestMapping("/listpage") @ResponseBody public PageList listpage(UserQuery userQuery){ userQuery.setType(2L);//2表示老师 return userService.listpage(userQuery); } @PostMapping("/addTeacher") @ApiOperation("添加教师接口") @ResponseBody @PreAuthorize("hasRole('管理员')") public Message addTeacher(User user){ if(StringUtils.isEmpty(user.getUsername())){ return Message.error("请填写用户名"); } if(StringUtils.isEmpty(user.getPassword())){ return Message.error("请填写密码"); } if(StringUtils.isEmpty(user.getEmail())){ return Message.error("请填写邮箱"); } if(StringUtils.isEmpty(user.getTel())){ return Message.error("请填写手机号"); } User userByUserName = userService.findUserByUserName(user.getUsername()); if(userByUserName!=null){ return Message.error("用户名已存在"); } user.setType(2); if(userService.addUser(user)<=0){ return Message.error("教师添加失败"); } //保存工作流程操作 IdentityService is = engine.getIdentityService(); // 添加用户组 org.activiti.engine.identity.User userInfo = userService.saveUser(is, user.getUsername()); Group tGroup = new GroupEntityImpl(); tGroup.setId("tGroup"); userService.saveRel(is, userInfo, tGroup); operaterLogService.add("添加教师成功,教师名称:"+user.getUsername()); return Message.success(); } @PostMapping("/editSaveStu") @ApiOperation("修改教师接口") @PreAuthorize("hasRole('管理员')") @ResponseBody public Message editSaveStu(User user){ if(StringUtils.isEmpty(user.getUsername())){ return Message.error("请填写用户名"); } if(StringUtils.isEmpty(user.getEmail())){ return Message.error("请填写邮箱"); } if(StringUtils.isEmpty(user.getTel())){ return Message.error("请填写手机号"); } User userByUserName = userService.findUserByUserName(user.getUsername()); if(userByUserName!=null){ if(!userByUserName.getId().equals(user.getId())){ return Message.error("该用户名已存在"); } } try { userService.editSaveUser(user); operaterLogService.add("编辑教师成功,教师名称:"+user.getUsername()); return Message.success(); } catch (Exception e) { e.printStackTrace(); return Message.error("教师信息编辑失败"); } } }看完上述内容，你们掌握Java怎样实现在线选课系统的方法了吗？如果还想学到更多技能或想了解更多相关内容，欢迎关注编程网行业资讯频道，感谢各位的阅读！
