六、模塊實現：登錄控制模塊（4）

1. 登錄控制模塊
  1. 登錄攔截器

在包“com.example.demo”中新建一個“LoginInterceptor”類，代碼如下：

package com.example.demo;

import java.io.PrintWriter;

/**

* 登錄攔截器

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Component;

import org.springframework.web.servlet.HandlerInterceptor;

import com.example.demo.vo.Json;

import com.fasterxml.jackson.databind.ObjectMapper;

@Component

public class LoginInterceptor implements HandlerInterceptor {

private final Logger logger = LoggerFactory.getLogger(this.getClass());

@Autowired

private ObjectMapper mapper;//Jackson使用ObjectMapper類將POJO對象序列化成JSON字符串，也能將JSON字符串反序列化成POJO對象。

@Override

public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { //請求進入這個攔截器

logger.info("進入攔截器...");

HttpSession session = request.getSession();

if(session.getAttribute("user") == null){//判斷session中有沒有user信息

logger.info("session中沒有user信息");

//ajax異步請求

if("XMLHttpRequest".equalsIgnoreCase(request.getHeader("X-Requested-With"))){

logger.info("ajax異步請求");

Json j = new Json();

j.setSuccess(false);

j.setMsg("session會話超時，請重新登錄！");

response.setContentType("application/json;charset=UTF-8");

PrintWriter writer = response.getWriter();

writer.write(mapper.writeValueAsString(j));//將對象轉成字符串

logger.info(mapper.writeValueAsString(j));

writer.close();

response.flushBuffer();

return false;

}else {

logger.info("頁面請求");

response.sendRedirect("/login");//沒有user信息的話進行路由重定向到登錄頁面

return false;

}

logger.info("登錄攔截驗證通過。");

return true;//有的話就繼續操作

}

每一個配置爲攔截的http請求都會執行preHandle方法，可以在這裏檢查用戶的session是否爲空來進行登錄驗證，因爲請求有可能是異步的，所以對於異步的請求不能直接跳轉頁面，而是返回json數據。

修改在包“com.example.demo”中新建一個“WebConfig”類，代碼如下：

package com.example.demo;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.beans.factory.annotation.Value;

import org.springframework.context.annotation.Configuration;

import org.springframework.web.servlet.config.annotation.InterceptorRegistration;

import org.springframework.web.servlet.config.annotation.InterceptorRegistry;

import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;

import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration

public class WebConfig implements WebMvcConfigurer {

@Autowired

private LoginInterceptor loginInterceptor;//登錄攔截器

//圖片存放根路徑，從application.yml中讀取upload

@Value("${upload}")

private String UPLOAD_PATH;

/**

* 文件上傳

@Override

public void addResourceHandlers(ResourceHandlerRegistry registry) {

//外部靜態資源映射路徑，用來上傳文件

String filePath = "file:" + UPLOAD_PATH;

registry.addResourceHandler("/upload/**").addResourceLocations(filePath);

}

//攔截器

@Override

public void addInterceptors(InterceptorRegistry registry) {

//登錄攔截的管理器

InterceptorRegistration registration = registry.addInterceptor(loginInterceptor);//攔截的對象會進入這個類中進行判斷

registration.addPathPatterns("/**");//所有路徑都被攔截

registration.excludePathPatterns("/","/login","/UserController/login","/kaptcha","/static/**","/UserController/logout","/upload/**");//添加不攔截路徑

}

在WebConfig中增加了攔截器的設置。

1. 1. 驗證碼接口

修改在包“com.example.demo.controller”中新建一個“HomeController”類，代碼如下：

package com.example.demo.controller;

/**

* 後臺管理主頁，登錄頁面，驗證碼生成

import java.awt.image.BufferedImage;

import javax.imageio.ImageIO;

import javax.servlet.ServletOutputStream;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.servlet.ModelAndView;

import com.example.demo.model.User;

import com.example.demo.service.PermissionService;

import com.google.code.kaptcha.Constants;

import com.google.code.kaptcha.Producer;

@Controller

public class HomeController {

private final Logger logger = LoggerFactory.getLogger(this.getClass());

@Autowired

private Producer captchaProducer;//驗證碼

@Autowired

private PermissionService permissionService;// 注入業務層的service

// 未加入@ResponseBody用來返回數據給頁面

@RequestMapping("/index")

public String index(HttpServletRequest request,Model model) {

HttpSession session = request.getSession();

User user = (User)session.getAttribute("user");

logger.info(user.getUsername());

logger.info(user.getId());

model.addAttribute("username", user.getUsername());

model.addAttribute("userid", user.getId());

model.addAttribute("menulist", permissionService.getUserMenu(user.getId()));

return "admin/index";

}

// 未加入@ResponseBody用來返回數據給頁面

@RequestMapping("/home")

public String home(Model model) {

return "admin/home";

}

// 未加入@ResponseBody用來返回數據給頁面

@RequestMapping("/")

public String login(Model model) {

return "admin/login";

}

// 未加入@ResponseBody用來返回數據給頁面

@RequestMapping("/login")

public String login2(Model model) {

return "admin/login";

}

@RequestMapping("/kaptcha")

public ModelAndView getKaptchaImage(HttpServletRequest request, HttpServletResponse response) throws Exception {

HttpSession session = request.getSession();

String code = (String)session.getAttribute(Constants.KAPTCHA_SESSION_KEY);

logger.info("******************驗證碼是: " + code + "******************");

response.setDateHeader("Expires", 0);

// Set standard HTTP/1.1 no-cache headers.

response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");

// Set IE extended HTTP/1.1 no-cache headers (use addHeader).

response.addHeader("Cache-Control", "post-check=0, pre-check=0");

// Set standard HTTP/1.0 no-cache header.

response.setHeader("Pragma", "no-cache");

// return a jpeg

response.setContentType("image/jpeg");

// create the text for the image

String capText = captchaProducer.createText();

// store the text in the session

session.setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);

// create the image with the text

BufferedImage bi = captchaProducer.createImage(capText);

ServletOutputStream out = response.getOutputStream();

// write the data out

ImageIO.write(bi, "jpg", out);

try {

out.flush();

} finally {

out.close();

}

return null;

}

增加了登錄頁面路徑映射以及驗證碼生成接口。

修改在包“com.example.demo”中新建一個“MisApplication”類，代碼如下：

package com.example.demo;

import java.util.Properties;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.context.annotation.Bean;

import com.google.code.kaptcha.Constants;

import com.google.code.kaptcha.impl.DefaultKaptcha;

import com.google.code.kaptcha.util.Config;

@SpringBootApplication

public class MisApplication {

public static void main(String[] args) {

SpringApplication.run(MisApplication.class, args);

}

/**

* 驗證碼

* @return

@Bean

public DefaultKaptcha captchaProducer() {

DefaultKaptcha captchaProducer = new DefaultKaptcha();

Properties properties = new Properties();

// properties.setProperty(Constants.KAPTCHA_BORDER, "yes");

// properties.setProperty(Constants.KAPTCHA_BORDER_COLOR, "red");

// properties.setProperty(Constants.KAPTCHA_TEXTPRODUCER_FONT_COLOR, "blue");

properties.setProperty(Constants.KAPTCHA_TEXTPRODUCER_FONT_SIZE, "50");

properties.setProperty(Constants.KAPTCHA_TEXTPRODUCER_FONT_NAMES, "宋體,楷體,微軟雅黑");

properties.setProperty(Constants.KAPTCHA_TEXTPRODUCER_CHAR_LENGTH, "4");

properties.setProperty(Constants.KAPTCHA_TEXTPRODUCER_CHAR_STRING, "0123456789");

properties.setProperty(Constants.KAPTCHA_IMAGE_WIDTH, "120");

properties.setProperty(Constants.KAPTCHA_IMAGE_HEIGHT, "50");

properties.setProperty(Constants.KAPTCHA_SESSION_CONFIG_KEY, "code");

Config config = new Config(properties);

captchaProducer.setConfig(config);

return captchaProducer;

}

對驗證碼的生成進行配置。

1. 1. 登錄與註銷接口

修改在包“com.example.demo.controller”中新建一個“UserController”類，代碼如下：

package com.example.demo.controller;

import java.io.File;

import java.io.IOException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpSession;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.beans.factory.annotation.Value;

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

import org.springframework.util.StringUtils;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.ResponseBody;

import org.springframework.web.multipart.MultipartFile;

import com.example.demo.model.User;

import com.example.demo.service.UserService;

import com.example.demo.util.SnowflakeIdWorker;

import com.example.demo.vo.DataTableResult;

import com.example.demo.vo.Json;

import com.example.demo.vo.UserVO;

import com.google.code.kaptcha.Constants;

@Controller

@RequestMapping("/UserController")

public class UserController {

private final Logger logger = LoggerFactory.getLogger(this.getClass());

private String prefix = "admin/user";// 頁面的路徑，注意admin前面不要有/

// 圖片存放根路徑，從application.yml中讀取upload

@Value("${upload}")

private String UPLOAD_PATH;

@Autowired

private UserService userService;// 注入業務層的service

// 未加入@ResponseBody用來返回數據給頁面

@RequestMapping("view")

public String view(Model model) {

// String str="個人";

// model用來回傳數據給前端頁面

// setTitle(model, new TitleVo("列表", str+"管理", true,"歡迎進入"+str+"頁面", true, false));

return prefix + "/view";

}

// @ResponseBody，直接通過js異步返回數據給頁面

@RequestMapping("list")

@ResponseBody

public DataTableResult list(HttpServletRequest request, UserVO userVO) {

// DataTableResult返回給datatables控件的數據格式

DataTableResult result = new DataTableResult();

// 獲取分頁參數

int start = Integer.parseInt(request.getParameter("start"));

int length = Integer.parseInt(request.getParameter("length"));

// 獲取排序字段

String orderIdx = request.getParameter("order[0][column]");

// 獲取排序字段名

String orderField = request.getParameter("columns[" + orderIdx + "][name]");

// 獲取排序方式，降序desc或者升序asc

String orderDir = request.getParameter("order[0][dir]");

// 調用分頁查詢方法

result = userService.selectUserListPage(userVO, start, length, orderField, orderDir);

// result.setDraw(userVO.getDraw());

return result;

}

// @ResponseBody，直接通過js異步返回數據給頁面

@RequestMapping("insert")

@ResponseBody

public Json insert(User user) {

Json j = new Json();

if (userService.insert(user) > 0) {

j.setSuccess(true);

j.setMsg("添加成功！");

} else {

j.setSuccess(false);

j.setMsg("添加失敗！");

}

return j;

}

// @ResponseBody，直接通過js異步返回數據給頁面

@RequestMapping("update")

@ResponseBody

public Json updateById(User user) {

Json j = new Json();

if (userService.updateById(user) > 0) {

j.setSuccess(true);

j.setMsg("修改成功！");

} else {

j.setSuccess(false);

j.setMsg("修改失敗！");

}

return j;

}

// @ResponseBody，直接通過js異步返回數據給頁面

@RequestMapping("select")

@ResponseBody

public Json selectById(User user) {

Json j = new Json();

j.setSuccess(true);

j.setObj(userService.selectById(user.getId()));

return j;

}

// @ResponseBody，直接通過js異步返回數據給頁面

@RequestMapping("delete")

@ResponseBody

public Json delete(HttpServletRequest request) {

Json j = new Json();

String ids = request.getParameter("ids");

if (!StringUtils.isEmpty(ids)) {

j.setSuccess(true);

j.setObj("成功刪除" + userService.delete(ids) + "條記錄");

} else {

j.setSuccess(false);

j.setMsg("沒有需要刪除的記錄！");

}

return j;

}

// @ResponseBody，直接通過js異步返回數據給頁面

// @RequestParam("file[]") MultipartFile[] file 多個文件

@RequestMapping("upload")

@ResponseBody

public Json upload(HttpServletRequest request, @RequestParam("file") MultipartFile file) {

Json j = new Json();

if (!file.isEmpty()) {

try {

String originalFilename = file.getOriginalFilename();

// 隨機文件名

String newFileName = SnowflakeIdWorker.getUUID()

+ originalFilename.substring(originalFilename.lastIndexOf("."));

// 上傳文件路徑

File upload = new File(UPLOAD_PATH, "images/");

if (!upload.exists())

upload.mkdirs();

String uploadPath = upload + "\\";

logger.info("uploadPath = " + uploadPath);

File uploadfile = new File(uploadPath + newFileName);

// 將上傳文件保存到一個目標文件當中

file.transferTo(uploadfile);

j.setSuccess(true);

j.setObj("/upload/images/" + newFileName);

} catch (IllegalStateException | IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

j.setSuccess(false);

j.setObj("上傳異常");

}

} else {

j.setSuccess(false);

j.setObj("上傳失敗");

}

return j;

}

/**

* 登錄驗證

* @param request

* @param user

* @return

// @ResponseBody，直接通過js異步返回數據給頁面

@RequestMapping("login")

@ResponseBody

public Json login(HttpServletRequest request, User user) {

Json j = new Json();

HttpSession session = request.getSession();

String code = (String) session.getAttribute(Constants.KAPTCHA_SESSION_KEY);

String kaptcha = request.getParameter("kaptcha");

if (kaptcha.equals(code)) {

// 驗證碼正確

User loginUser = userService.selectByUser(user);

if (loginUser != null) {

j.setSuccess(true);

loginUser.setPassword("");// 密碼不回傳

j.setObj(loginUser);

j.setMsg("登錄成功！");

session.setAttribute("user", loginUser);// 保存session會話

} else {

j.setSuccess(false);

j.setMsg("登錄失敗！");

}

} else {

j.setSuccess(false);

j.setMsg("驗證碼錯誤！");

}

return j;

}

/**

* 註銷

* @param request

* @param model

* @return

// 未加入@ResponseBody用來返回數據給頁面

@RequestMapping("logout")

public String logout(HttpServletRequest request,Model model) {

HttpSession session = request.getSession();

session.removeAttribute("user");

return "admin/login";

}

增加了用戶登錄與註銷接口。

1. 1. 登錄界面

添加登錄界面文件，在“admin”文件夾-> 右鍵->new->file，輸入“login.html”，代碼如下：

<!DOCTYPE html>

<head>

<!--[if lt IE 9]>

<![endif]-->

if (window.top !== window.self) {

window.top.location = window.location;

}

</script>

</head>

<form>

<p class="m-t-md">登錄XXX後臺管理系統</p>

</div>

<a href="">忘記密碼了？</a>

</form>

</div>

</div>

$(document).ready(function () {

//toastr選項

toastr.options = {

"positionClass": "toast-bottom-center",

}

$("#btn_login").click(function(){

var username=$("#username").val();

var password=$("#password").val();

var kaptcha=$("#kaptcha").val();

if(username.length==0 || password.length==0 || kaptcha.length==0){

toastr.error("用戶名、密碼或者驗證碼爲空！", '錯誤！');

}else{

//異步添加數據

$.ajax({

type: "post",

data: {

username:$("#username").val(),

password:$("#password").val(),

kaptcha:$("#kaptcha").val(),

url: "/UserController/login",//後臺處理地址

success: function (data) {

if(data.success){

toastr.success(data.msg, '登錄成功！');

location.href="/index";

}else{

toastr.error(data.msg, '登錄失敗！');

}

}); // end ajax

}

});//end btn_login

});//end ready

</script>

</body>

</html>

1. 1. 動態加載菜單

修改主界面文件，在“admin”文件夾中的“index.html”，代碼如下：

<!DOCTYPE html>

<head>

<title> hAdmin- 主頁</title>

<!--[if lt IE 9]>

<![endif]-->

</head>

</div>

</span>

</a>

</div>

<div class="logo-element">管理系統

</div>

</li>

<li>

</a>

</li>

</a>

</li>

</ul>

</li>

</ul>

</div>

</nav>

</div>

</form>

</div>

<li>

</li>

</a>

</a>

<strong>小四</strong> 是不是隻有我死了,你們纔不罵爵跡

<br>

</div>

</li>

<li>

</a>

<strong>二愣子</strong> 呵呵

<br>

</div>

</li>

<li>

<i class="fa fa-envelope"></i> <strong> 查看所有消息</strong>

</a>

</div>

</li>

</ul>

</li>

</a>

<li>

<div>

<i class="fa fa-envelope fa-fw"></i> 您有16條未讀消息

</div>

</a>

</li>

<li>

<div>

<i class="fa fa-qq fa-fw"></i> 3條新回覆

</div>

</a>

</li>

<li>

</a>

</div>

</li>

</ul>

</li>

</ul>

</nav>

</div>

</div>

</div>

</body>

</html>

利用“th:each”對後臺返回的"${menulist}"數據進行二重遍歷，動態構造出用戶的菜單。

打開瀏覽器，先輸入地址http://127.0.0.1:8080/index，會發現跳轉到登錄頁面，效果如下：

以不同身份登錄時菜單不同，以用戶名和密碼都爲“e”登錄：

點擊右上角的註銷鏈接後，以用戶名和密碼都爲“a”登錄：

還可以通過後臺動態修改角色的權限和用戶的角色，注意首先是對角色分配權限，然後再把角色分配給用戶。

完整的項目源碼已經分享在GitHub網站上（https://github.com/gjq246/springboot2author）。

六、模塊實現：登錄控制模塊（4）

Ubuntu16.04下安裝OpenCV3.2.0(轉)

Keras中實現模型加載與測試（以mnist爲例）

spring cloud config---Could not resolve placeholder 'foo' in string value "${foo}"

Depends:libreoffice-base but it is not going to be installed

Ubuntu 16.04 安裝 Anaconda

https://yachay.unat.edu.pe/blog/index.php?comment_area=format_blog&comment_component=blog&comment_co

linux以太網驅動總結