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SpringMVC_2023_11_28_2 SpringMVC_进阶(文件的上传)

发布时间 2023-11-29 11:47:10作者: Kbaor

SpringMVC_进阶(文件的上传)

2023-11-29 10:47:35 星期三

依赖引入

 <dependencies>
        <!--servlet依赖-->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
            <scope>provided</scope>
        </dependency>
        <!--spring基础依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.3.20</version>
        </dependency>
        <!--spring web依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>5.3.20</version>
        </dependency>
        <!--spring mvc 依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.3.20</version>
        </dependency>
        <!--文件上传-->
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.4</version>
        </dependency>
    </dependencies>

spring-mvc.xml核心配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd">

    <!--处理器映射器-->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping"/>

    <!--处理器适配器-->
    <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter"/>

    <!--处理器-->
    <context:component-scan base-package="com.bboy.controller"/>

    <!--
        文件上传的加载器:
        注意：id的内容必须是 multipartResolver
    -->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <!--文件上传的最大值-->
        <property name="maxUploadSize" value="10485760"/>
    </bean>

    <!--视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"/>

</beans>

web.xml 配置文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <!--前端控制器-->
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-mvc.xml</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

MyFileController

package com.bboy.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.util.UUID;

/**
 * @类描述：
 * @作者：秦帅
 * @时间：2023/11/29 0029 10:55:21
 */
@Controller
public class MyFileController {
    /**
     * fileUpload(MultipartFile myfile, HttpServletRequest request)
     * 参数-1：MultipartFile myfile
     *      指代上传的文件，参数名必须与页面中 file组件的name值一致
     *      (注意：此处的请求地址不要使用/upload,因为后面有/upload的其它配置)
     */
    @RequestMapping("/fileUpload")
    public String fileUpload(MultipartFile myfile, HttpServletRequest request, Model model)throws Exception{
        //1.获取本地服务目录
        String path = request.getSession().getServletContext().getRealPath("upload");
        //2. 判断该目录是否存在
        File file = new File(path);
        if(!file.exists()){
            file.mkdirs();
        }
        //3. 将上传的文件保存到本地服务
        //3.1 获取文件原始名称
        String old_name = myfile.getOriginalFilename();
        //3.2 生成新的名称：随机生成
        String new_name = UUID.randomUUID().toString().replace("-","");
        //3.3 新的名称 = 随机生成的名字 + 文件的后缀名
        String hzm = old_name.substring(old_name.lastIndexOf(".")+1);
        new_name = new_name +"." + hzm;
        //3.4 定义上传的文件
        File target = new File(path+"/"+new_name);
        //3.5 直接上传
        myfile.transferTo(target);
        //4.获取网络访问的地址
        //4.1 获取基本路径 http://locahost:8080/xxx/upload
        String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+request.getContextPath()+"/";
        String imgPath = "/upload/"+new_name;
        String imgHttpPath = basePath+imgPath;
        System.out.println(imgHttpPath);
        //-5.将图片的显示路径返回给页面
        model.addAttribute("imgHttpPath",imgHttpPath);
        return "/WEB-INF/show.jsp";
    }
}

index.jsp

<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" isELIgnored="false" %>
<!DOCTYPE html>
<html>
<head>
    <title>JSP - Hello World</title>
</head>
<form action="/fileUpload" method="post" enctype="multipart/form-data" >
    <input type="file" name="myfile"/><br/>
    <input type="submit" value="上传"/>
</form>
</html>

show.jsp

<%--
  Created by IntelliJ IDEA.
  User: new
  Date: 2023/11/28
  Time: 10:21
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
    <img src="${imgHttpPath}"/>
</body>
</html>