bootstrap登錄，bootstrap實現單頁面跳轉_SpringBoot攔截器,國際化,登錄實現

首先將模板文件導入resources/templates,配置MyMvcConfig

@Configurationpublic?class?MyMvcConfig?implements?WebMvcConfigurer?{//      無邏輯視圖跳轉    @Override    public void addViewControllers(ViewControllerRegistry registry) {        registry.addViewController("/").setViewName("index");????????registry.addViewController("/index.html").setViewName("index");????}}

通過在繼承了WebMvcConfigurer接口的MyMvcConfig類中注冊bean或重寫方法，來自定義SpringBoot底層默認的代碼

此時啟動ConfigApplication主類，在地址欄輸入"localhost:8080/"或"localhost:8080/index.html",無邏輯跳轉到index,addViewControllers方法的好處是實現起來比寫一個Controller類簡單,但只能實現無邏輯跳轉

現在瀏覽器頁面中沒有配置的css樣式和img，在html標簽中加入如下配置

xmlns:th="http://www.thymeleaf.org"

bootstrap登錄、Spring官方支持的服務的渲染模板中，并不包含jsp。而是Thymeleaf等，而Thymeleaf與SpringMVC的視圖技術，及SpringBoot的自動化配置集成非常完美，幾乎沒有任何成本，只用關注Thymeleaf的語法即可。也就是說jsp已經被SpringBoot官方淘汰。

<link th:href="@{/css/bootstrap.min.css}"  rel="stylesheet"><link th:href="@{/css/signin.css}" rel="stylesheet">

Thymeleaf語言非常簡單，只需在html標簽前加 "th:" ,后邊類似EL表達式，取地址用@{},取值用${},導入用~{}等等

這樣配置后，html頁面中的css樣式終于顯示了出來

i18n頁面國際化：

bootstrap-server？Springboot底層默認實現了國際化，先來看一下官方國際化是怎樣配置的：

進入AcceptHeaderLocaleResolver

可以看到這個類繼承了LoclaResolver接口，所有我們自定義國際化配置時的類也模仿官方來做

    public Locale resolveLocale(HttpServletRequest request) {        Locale defaultLocale = this.getDefaultLocale();        if (defaultLocale != null && request.getHeader("Accept-Language") == null) {            return defaultLocale;        } else {            Locale requestLocale = request.getLocale();            List supportedLocales = this.getSupportedLocales();            if (!supportedLocales.isEmpty() && !supportedLocales.contains(requestLocale)) {                Locale supportedLocale = this.findSupportedLocale(request, supportedLocales);                if (supportedLocale != null) {                    return supportedLocale;                } else {                    return defaultLocale != null ? defaultLocale : requestLocale;                }            } else {                return requestLocale;            }        }    }

網頁攔截、這是官方的國際化核心方法，可以看出官方是通過將Locale存入request的頭文件配置中，再在此方法中取出，如果locale為空，則使用默認國際化，若不為空則new一個與傳入值對應的locale，雖然官方給我們實現了，但是從頭文件里取出參數難免對我門不友好，操作復雜，所以我們可以自定義一個國際化配置器

首先，將index中轉換的標簽修改

      class=      class=

我們直接將參數寫在url里，這樣取出會很方便，zh_CN即為簡體中文，依此類推，接著要新建默認配置文件，簡體中文配置文件和英文配置文件

idea提供了編寫國際化配置的可視化界面，為每個要國際化的文本位置都寫配置

public class MyLocale implements LocaleResolver {    @Override    public Locale resolveLocale(HttpServletRequest httpServletRequest) {        //獲取默認Locale        Locale locale = Locale.getDefault();????????//獲取url中的language參數        String language=httpServletRequest.getParameter("language");        if(!StringUtils.isEmpty(language)){????????????//若不為空則用_分割，再拼接            String[] strings = language.split("_");            System.out.println(language);            locale = new Locale(strings[0], strings[1]);        }        return locale;    }    @Override????public?void?setLocale(HttpServletRequest?httpServletRequest,?HttpServletResponse?httpServletResponse,?Locale?locale)?{    }}

bootstrap5、MyLocale類就繼承LocaleResolver接口，實現它的全部方法，只對resolveLocale重寫

再MyMvcConfig中注冊bean

//    注冊LocaleResolver國際化    @Bean    public LocaleResolver localeResolver(){        return new MyLocale();    }

國際化完成

登錄功能實現：

頁面已攔截、

form表單提交到/login請求中，編寫Controller類

    @RequestMapping("/login")    public String login(Model model,                        @RequestParam("username") String username,                        @RequestParam("password") String password,                        HttpSession httpSession){        if(!StringUtils.isEmpty(username) & "123".equals(password)){            return "redirect:/main.html";        }        httpSession.setAttribute("loginUser",username);        model.addAttribute("msg","用戶名或密碼錯誤");        return "index";    }

若username不為空且password等于123，重定向到main.html請求中，反之則在session和model中都加入錯誤信息后返回到index主頁

配置攔截器，防止用戶自行在地址欄輸入main.html直接進入后臺

//攔截器public class LoginInterceptor implements HandlerInterceptor {    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {        String msg = (String)request.getSession().getAttribute("loginUser");        if(msg==null){            //未登錄            request.setAttribute("loginMsg","請先登錄");//            response.sendRedirect("/index.html");            request.getRequestDispatcher("/index.html").forward(request,response);            return false;        }else {            return true;        }    }}

若未登錄則跳轉到登陸頁面，并阻止放行，若已登錄則放行

Spring boot，注冊攔截器

//    注冊攔截器@Overridepublic void addInterceptors(InterceptorRegistry registry) {    registry.addInterceptor(new LoginInterceptor()).addPathPatterns("/main.html");}

只攔截/main.html請求

用戶輸入/main.html請求時若未登錄會攔截，已登錄會直接進入后臺

頁面被攔截怎么取消，用戶注銷實現：

    @RequestMapping("/del")    public String del(HttpSession httpSession){        httpSession.removeAttribute("loginUser");        return "index";????}

class="nav-link" th:href="@{/del}">Sign out

展示全部成員信息：用Thymeleaf-each循環實現

@Controllerpublic?class?UserController?{    @Autowired????private?EmployeeDao?employeeDao;    @RequestMapping("/Users")????public?String?Users(Model?model){        Collection employeeAll = employeeDao.getEmployeeAll();        model.addAttribute("users",employeeAll);        return "/list";????}}

@Repositorypublic class EmployeeDao {    public static Map employMap=null;    @Autowired????public?DepartmentDao?departmentDao;    static {        employMap = new HashMap<>();        employMap.put(101,new Employee(1001,"張三","123@qq.com",1,new Department(101,"吃飯部")));        employMap.put(102,new Employee(1002,"李四","122@qq.com",1,new Department(102,"學習部")));        employMap.put(103,new Employee(1003,"張四","123@qq.com",0,new Department(103,"睡覺部")));        employMap.put(104,new Employee(1004,"李三","121@qq.com",1,new Department(104,"王者部")));        employMap.put(105,new Employee(1005,"李張三","223@qq.com",0,new Department(105,"吃屎部")));????}    //查詢全部員工信息    public CollectiongetEmployeeAll(){        return employMap.values();????}}

@Data@NoArgsConstructorpublic class Employee {    private Integer id;    private String lastName;    private String email;    private Integer gender;    private Department department;????private?Date?birth;    public Employee(Integer id, String lastName, String email, Integer gender, Department department) {        this.id = id;        this.lastName = lastName;        this.email = email;        this.gender = gender;        this.department = department;        this.birth = new Date();    }}

  <tbody>    <tr th:each="user,Employee:${users}" >      <th th:text="${user.id}">th>      <th th:text="${user.lastName}">th>      <th th:text="${user.email}">th>      <th th:text="${user.gender}">th>      <th th:text="${user.department}">th>    tr>  tbody>

功能實現