SpringBoot--web开发常见配置

拦截器

package com.model.config;

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

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

/**
 * @Description:测试类
 * @Author: 张紫韩
 * @Crete 2021/8/4 18:31
 */
public class MyHandlerInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession();
        return session.getAttribute("loginUser") != null;
    }

    @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 {

    }
}

package com.model.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
 * @Description:测试类
 * @Author: 张紫韩
 * @Crete 2021/8/4 18:30
 */
@Configuration
//配置类实现扩展类接口
public class MyWebMvcConfig implements WebMvcConfigurer {

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new MyHandlerInterceptor())
                .addPathPatterns("/**")
                .excludePathPatterns("/index","/","/toLogin","/doLogin","/css/**","/js/**","/images/**","/fonts/**");
    }
}

文件上传与下载

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<form th:action="@{/doLogin}" method="post" enctype="multipart/form-data">
    头像：<input type="file" name="picture">
    <br>
    生活照：<input type="file" name="photos" multiple>
    <br>
    <input type="submit" th:value="提交">
</form>
</body>
</html>

package com.model.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;

/**
 * @Description:测试类
 * @Author: 张紫韩
 * @Crete 2021/8/4 18:43
 */
@Controller
public class PageController {

    @RequestMapping("/toLogin")
    public String toForm(){
        return "form";
    }
    @RequestMapping("/doLogin")
    public String foForm(@RequestPart("picture")MultipartFile picture,
                         @RequestPart("photos")MultipartFile[] photos) throws IOException {

        if (!picture.isEmpty()) {
            String filename = picture.getOriginalFilename();
            picture.transferTo(new File("D:\\qq\\IDEA\\IdeaProjects\\technical_framework\\SpringBooot\\springboot11\\src\\main\\resources\\static\\images\\" + filename));

        }
        if (photos.length>0){
            for (MultipartFile photo : photos) {
                if (!photo.isEmpty()) {
                    String filename = photo.getOriginalFilename();
                    photo.transferTo(new File("D:\\qq\\IDEA\\IdeaProjects\\technical_framework\\SpringBooot\\springboot11\\src\\main\\resources\\static\\images\\" + filename));
                }
            }
        }
        return "redirect:/index";
    }


}

异常处理：
4. 我们在templates 中自定义 error/404.html，5xx.html 。springboot会对这两个页面进行解析，遇到错误时，会自动跳转到这两个界面

Web原生组件的注入（Servlet,listener,Filter）

package com.model.servlet;

import org.springframework.boot.autoconfigure.web.ServerProperties;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @Description:测试类
 * @Author: 张紫韩
 * @Crete 2021/8/4 20:33
 * 注入源生组件Servlet
 */
//第一种使用注解，将我们自定义的组件放入到容器中
// 第二中我们使用配置文件将组件放到容器中
//@WebServlet(urlPatterns = "/my")
public class MyServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
       resp.getWriter().write("6666");
    }
}

package com.model.servlet;

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletListenerRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.Arrays;
import java.util.EventListener;

/**
 * @Description:测试类
 * @Author: 张紫韩
 * @Crete 2021/8/4 20:52
 */

@Configuration(proxyBeanMethods = true)//保证我们依赖的组件是单实例的
public class MyRegistrationBeanConfig {

    @Bean
    public ServletRegistrationBean<MyServlet> servletRegistrationBean(){
        MyServlet servlet = new MyServlet();
        ServletRegistrationBean<MyServlet> bean = new ServletRegistrationBean<>(servlet, "/my");
        return bean;
    }
    @Bean
    public FilterRegistrationBean<MyFilter> filterRegistrationBean() {
        MyFilter filter = new MyFilter();
        FilterRegistrationBean<MyFilter> registration = new FilterRegistrationBean<>(filter);
        registration.setUrlPatterns(Arrays.asList("/css/*"));
        return registration;
    }

    @Bean
    public ServletListenerRegistrationBean<MyListener> listerRegistrationBean() {
        MyListener listener = new MyListener();
        ServletListenerRegistrationBean<MyListener> bean = new ServletListenerRegistrationBean<>(listener);
        return bean;
    }

}

定制化原理

原文地址：https://www.cnblogs.com/zzhAylm/p/15099963.html