Spring Boot web开发（未完待续）

addViewController请求

attention:

想要把网站的图标换掉就在static下放一个 favicon.ico 的图标图片即可

Spring MVC 5.0.5官方文档

static和template

springboot整合了springmvc的拦截功能。拦截了所有的请求。默认放行的资源是：resources/static/ 目录下所有静态资源。（不走controller控制器就能直接访问到资源）。

html页面如果放在resources/templates目录下，则需要走controller控制器，controller放行，允许该资源访问，该资源才能被访问到。否则就会报404错误（它不可以直接被访问）。

因此默认时访问public目录下的index.html

通过配置类来extends WebMvcConfigurationSupport实现访问template目录下的login.html下

(当然通过controller来访问也是可以的，但是Spring Boot推荐采用配置类来实现)

重点提醒一下，一定要实现WebMvcConfigurer接口来访问，不要继承Support类

package com.example.webexpriment.config;

import com.example.webexpriment.component.MyLocaleResolver;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class MyMvcConfig implements WebMvcConfigurer {
    
    
    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
    
    

        //浏览器发送/gary请求，来到/success页面
        registry.addViewController("/").setViewName("login");
        System.out.println("WOC");
        registry.addViewController("/index.html").setViewName("login");
    }

    @Bean
    public LocaleResolver localeResolver(){
    
    
        return new MyLocaleResolver();
    }

}

搞定玩就可以访问主页了

附上Controller的访问方法

   @RequestMapping({
    
    "/","/index.html"})//数组
    public String index()
   {
    
    
        return "login";
    }

实现国际化功能（中英文）

1.编写properties的国际化文件

在html先里面修改 记得先导入模板引擎的提示功能xmlns:th=“http://www.thymeleaf.org”

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applicaltion.properties文件下加上

spring.messages.basename=i18n.login

2.导入thymeleaf模板引擎在html获取值

html标签

?l=zh_CN在thymeleaf中的写法：

The th:href attribute allows us to (optionally) have a working static href attribute in our template, so that our template links remained navigable by a browser when opened directly for prototyping purposes. (摘自官方文档)

<a class="btn btn-sm" th:href="@{/index.html(l='zh_CN')}">中文</a>
<a class="btn btn-sm"th:href="@{/index.html(l='en_US')}">English</a>

thymeleaf模板引擎来取国际化的值

参见thymeleaf官方文档

Variable Expressions: ${...} 
Selection Variable Expressions: *{...}
Message Expressions: #{...} 
Link URL Expressions: @{...} 
Fragment Expressions: ~{...}

修改example：

<h1 class="h3 mb-3 font-weight-normal" th:text="#{login.tip}">Please sign in</h1>

行内写法

		<label>
          <input type="checkbox" value="remember-me" > [[#{login.remember}]]
        </label>

提醒一下，记得设置IDE把编码自动转化为ASCII码

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
		<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
		<meta name="description" content="">
		<meta name="author" content="">
		<title>Signin Template for Bootstrap</title>
		<!-- Bootstrap core CSS -->
		<link href="asserts/css/bootstrap.min.css" rel="stylesheet">
		<!-- Custom styles for this template -->
		<link href="asserts/css/signin.css" rel="stylesheet">
	</head>

	<body class="text-center">
		<form class="form-signin" th:action="@{/user/login}" action="dashboard.html">
			<img class="mb-4" src="asserts/img/bootstrap-solid.svg" alt="" width="72" height="72">
			<h1 class="h3 mb-3 font-weight-normal" th:text="#{login.tip}">Please sign in</h1>
			<label class="sr-only" th:text="#{login.username}">Username</label>
			<input type="text" name="username" class="form-control" th:placeholder="#{login.username}" placeholder="Username" required="" autofocus="">
			<label class="sr-only"  th:text="#{login.password}">Password</label>
			<input type="password" name="password" class="form-control" th:placeholder="#{login.password}" placeholder="Password" required="">
			<div class="checkbox mb-3">
				<label>
          <input type="checkbox" value="remember-me" > [[#{login.remember}]]
             
        </label>
			</div>
			<button class="btn btn-lg btn-primary btn-block" type="submit" th:text="#{login.btn}">Sign in</button>
			<p class="mt-5 mb-3 text-muted">© 2017-2018</p>
			<a class="btn btn-sm" th:href="@{/index.html(l='zh_CN')}">中文</a>
			<a class="btn btn-sm"th:href="@{/index.html(l='en_US')}">English</a>
		</form>
	</body>
</html>

3.区域信息解析器，在链接上携带区域信息（Important）

需要自己写

package com.example.webexpriment.component;

import org.apache.tomcat.jni.Local;
import org.springframework.web.servlet.LocaleResolver;
import org.thymeleaf.util.StringUtils;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Locale;

/**
 * 可以在链接上携带区域信息
 */
public class MyLocaleResolver implements LocaleResolver {
    
    
    @Override
    public Locale resolveLocale(HttpServletRequest httpServletRequest) {
    
    
        String l = httpServletRequest.getParameter("l");
        System.out.println(l);
        //区域信息
        Locale locale= Locale.getDefault();
        //用StringUtils工具判断一下先
        if(!StringUtils.isEmpty(l))
        {
    
    
            String[] s = l.split("_");
            locale = new Locale(s[0], s[1]);
        }
        System.out.println(locale);
        return locale;
    }

    @Override
    public void setLocale(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Locale locale) {
    
    

    }
}

StringUtils

然后再配置类当中加入到容器当中 @Bean

package com.example.webexpriment.config;

        import com.example.webexpriment.component.MyLocaleResolver;
        import org.springframework.context.annotation.Bean;
        import org.springframework.context.annotation.Configuration;
        import org.springframework.web.servlet.LocaleResolver;
        import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
        import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
        import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class MyMvcConfig implements WebMvcConfigurer {
    
    
    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
    
    

        //浏览器发送/gary请求，来到/success页面
        registry.addViewController("/").setViewName("login");
        System.out.println("WOC");
        registry.addViewController("/index.html").setViewName("login");
    }

    @Bean
    public LocaleResolver localeResolver(){
    
    
        return new MyLocaleResolver();
    }

}

4.展示

系统默认：

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中文：

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English：

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登录访问dashboard.html

attention:

Map<String,Object>使用Object主要是为了方便赋值，无需强制类型转化。

修改访问的方式

<form class="form-signin" action="dashboard.html" th:action="@{/user/login}" method="post">

先写LoginController 来处理访问请求（再访问页面我们就不搞配置类了）

!!!修改html，input上面加上name属性

<input type="text" name="username" class="form-control" th:placeholder="#{login.username}" placeholder="Username" required="" autofocus="">

<input type="password" name="password" class="form-control" th:placeholder="#{login.password}" placeholder="Password" required="">

不加的话是编译器获取不到值

然后处理请求

package com.example.webexpriment.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.thymeleaf.util.StringUtils;

import java.util.Map;

@Controller
public class LoginController {
    
    
    @PostMapping(value="/user/login")
//    @RequestMapping(value="/user/login",method = RequestMethod.POST) 用上面更加方便
    //从请求参数上获取用户名和密码
    public String login(@RequestParam("username") String username,
                        @RequestParam("password")String password,
                        Map<String,Object>map){
    
    
        if(!StringUtils.isEmpty(username)&&"123456".equals(password))
        {
    
    
            //登陆成功
            return "dashboard";
        }
        else{
    
    
            //登录失败
            map.put("msg","用户名密码错误");
            return "login.html";
        }
    }
}

禁用模板引擎缓存并且刷新

attention

[1.$符号取上下文中的变量：

2.#](https://s.weibo.com/weibo?q=%23、*+和%24的区别： 1.%24符号取上下文中的变量：符号取thymeleaf工具中的方法、文字消息表达式：

Welcome to our grocery store!

3.　*{…}选择表达式一般跟在th:object后，直接选择object中的属性

操作

applicaltion.properties下加上

#禁用模板引擎的缓存
spring.thymeleaf.cache=false

再ctrl+F9来刷新

加上错误消息

p标签和if条件

参见官网文档

<!--	做一个判断,见官方文档，#strings为工具引用-->
	<p style="color: red" th:text="${msg}" th:if="${not #strings.isEmpty(msg)}"></p>

编写拦截器

1.重定向

防止表单的重复提交

package com.example.webexpriment.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.thymeleaf.util.StringUtils;

import java.util.Map;

@Controller
public class LoginController {
    
    

//    @RequestMapping(value="/user/login",method = RequestMethod.POST) 用上面更加方便
    //从请求参数上获取用户名和密码
@PostMapping(value="/user/login")
    public String login(@RequestParam("username") String username,
                        @RequestParam("password")String password,
                        Map<String,Object>map){
    
    
        if(!StringUtils.isEmpty(username)&&"123456".equals(password))
        {
    
    
            //登陆成功
            System.out.println("登录页面成功");
            //重定向，防止表单重复提交
            return "redirect:/main.html";
        }
        else{
    
    
            //登录失败
            map.put("msg","用户名密码错误");
            return "login";
        }
    }
}

package com.example.webexpriment.config;

        import com.example.webexpriment.component.MyLocaleResolver;
        import org.springframework.context.annotation.Bean;
        import org.springframework.context.annotation.Configuration;
        import org.springframework.web.servlet.LocaleResolver;
        import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
        import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
        import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class MyMvcConfig implements WebMvcConfigurer {
    
    
    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
    
    

        //浏览器发送/gary请求，来到/success页面
        registry.addViewController("/").setViewName("login");
        registry.addViewController("/index.html").setViewName("login");
        registry.addViewController("/main.html").setViewName("dashboard");
    }

    @Bean
    public LocaleResolver localeResolver(){
    
    
        return new MyLocaleResolver();
    }

}

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2.拦截器机制进行登陆检查

1）Controller当中post后传入一个session判断输入了没有

package com.example.webexpriment.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.thymeleaf.util.StringUtils;

import javax.servlet.http.HttpSession;
import java.util.Map;

@Controller
public class LoginController {
    
    

//    @RequestMapping(value="/user/login",method = RequestMethod.POST) 用上面更加方便
    //从请求参数上获取用户名和密码
@PostMapping(value="/user/login")
    public String login(@RequestParam("username") String username,
                        @RequestParam("password")String password,
                        Map<String,Object>map, HttpSession session){
    
    
        if(!StringUtils.isEmpty(username)&&"123456".equals(password))
        {
    
    
            //登陆成功
            System.out.println("登录页面成功");
            session.setAttribute("loginUser",username);
            //重定向，防止表单重复提交
            return "redirect:/main.html";
        }
        else{
    
    
            //登录失败
            map.put("msg","用户名密码错误");
            return "login";
        }
    }
}

2）添加新的类，实现接口

package com.example.webexpriment.component;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class LoginHandlerInterceptor implements HandlerInterceptor {
    
    
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    
    
        //预检查
        Object user = request.getSession().getAttribute("loginUser");

        if(user==null)
        {
    
    
            System.out.println("username为空");
            //拦截,返回登录页
            request.setAttribute("msg","没有权限请先登录");
            request.getRequestDispatcher("/index.html").forward(request,response);
            return false;
        }
        else{
    
    
            System.out.println(user);
            return true;
            //放行，已登录了
        }

    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
    
    

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
    
    

    }
}

3）配置类重写方法

@Override
//注册拦截器
public void addInterceptors(InterceptorRegistry registry) {
    
    
    //addPathPatterns()拦截哪些请求/**全部拦截
    registry.addInterceptor(new LoginHandlerInterceptor()).addPathPatterns("/**").excludePathPatterns("/index.html","/","/user/login");
    //静态资源Spring Boot自己已经搞定映射了，无需多管了
}

员工操作

实验要求

1）、RestfulCRUD：CRUD满足Rest风格；

URI： /资源名称/资源标识 HTTP请求方式区分对资源CRUD操作

	普通CRUD（uri来区分操作）	RestfulCRUD
查询	getEmp	emp—GET
添加	addEmp?xxx	emp—POST
修改	updateEmp?id=xxx&xxx=xx	emp/{id}—PUT
删除	deleteEmp?id=1	emp/{id}—DELETE

2）、实验的请求架构;

实验功能	请求URI	请求方式
查询所有员工	emps	GET
查询某个员工(来到修改页面)	emp/1	GET
来到添加页面	emp	GET
添加员工	emp	POST
来到修改页面（查出员工进行信息回显）	emp/1	GET
修改员工	emp	PUT
删除员工	emp/1	DELETE

3）、员工列表：

未完待续