SpringBoot上传文件并配置本地资源映射来访问文件

叁歲伎倆 2021-09-21 23:34 586阅读 0赞

### 目录 ###

*  1.准备工作
 *  2. 配置本地资源映射路径 addResourceHandlers
 *  3.上传代码

# 1.准备工作 #

1、新建一个SpringBoot项目加上web依赖, 所有依赖

<dependency>
    	<groupId>org.springframework.boot</groupId>
    	<artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    
    <dependency>
    	<groupId>org.thymeleaf</groupId>
    	<artifactId>thymeleaf-spring5</artifactId>
    </dependency>
    
    <dependency>
    	<groupId>org.springframework.boot</groupId>
    	<artifactId>spring-boot-starter-test</artifactId>
    	<scope>test</scope>
    </dependency>

2、application.properties

# 上传文件总的最大值
    spring.servlet.multipart.max-request-size=10MB
    #spring.servlet.multipart.max-request-size=10KB
    # 单个文件的最大值
    spring.servlet.multipart.max-file-size=10MB
    #spring.servlet.multipart.max-file-size=10KB
    
    # 文件上传路径, 当前项目根目录下的 uploadFile 目录
    pro.uploadPath=uploadFile

3、新建文件上传的静态文件 `index.html`

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>文件上传</title>
    </head>
        <body>
            <h1>文件上传</h1>
            <form method="post" action="/file/upload" enctype="multipart/form-data">
                <input type="file" name="file"><br>
                <input type="submit" value="提交">
            </form>
        </body>
    </html>

# 2. 配置本地资源映射路径 addResourceHandlers #

package com.pro.conf;
    
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
    
    @Configuration
    public class WebMvcConf implements WebMvcConfigurer { 
        @Value("${pro.uploadPath}")
        private String uploadPath;
    
        @Override
        public void addResourceHandlers(ResourceHandlerRegistry registry) { 
            registry.addResourceHandler(uploadPath + "/**") // 添加访问路径
                    // file: 当前项目根目录, 映射到真实的路径下的 uploadPath(变量)目录下
                    .addResourceLocations("file:" + uploadPath + "/");
        }
    }

# 3.上传代码 #

package com.pro.controller;
    
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.util.ResourceUtils;
    import org.springframework.web.bind.annotation.*;
    import org.springframework.web.multipart.MultipartFile;
    import org.springframework.web.multipart.MultipartHttpServletRequest;
    
    import javax.servlet.http.HttpServletRequest;
    import java.io.*;
    import java.text.SimpleDateFormat;
    import java.util.*;
    
    @RestController
    public class UploadController { 
        @Value("${pro.uploadPath}")
        private String uploadPath;
    
        /** * 获取文件路径 * @param request 请求体 * @param fileName 文件名称 * @return 文件路径 */
        public String getUploadPath(HttpServletRequest request, String fileName) { 
            return request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + "/" + uploadPath + "/" + fileName;
        }
    
        // 文件上传, 上传到当前项目根目录下的 uploadFile 目录
        @RequestMapping("/file/upload")
        public Object upload(@RequestParam("file") MultipartFile multipartFile, HttpServletRequest request) { 
            Map<String, Object> map = new HashMap();
            map.put("msg", "上传成功");
    
            if (multipartFile.isEmpty()) { 
                map.put("msg", "空文件");
                return map;
            }
    
            // 获取文件名
            String fileName = multipartFile.getOriginalFilename();
            if ("".equals(fileName)) { 
                map.put("msg", "文件名不能为空");
                return map;
            }
            System.out.println("上传文件原始的名字: " + fileName);
    
            // 使用uuid生成新文件名
            String newFileName = UUID.randomUUID().toString().replaceAll("-", "") + fileName.substring(fileName.lastIndexOf("."), fileName.length());
            System.out.println("保存的文件的新名字: " + newFileName);
    
            // 获取年月日的日期格式
            SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");
            String format = simpleDateFormat.format(new Date());
    
            // 生成以日期分割的文件路径
            File readPath = new File(uploadPath + File.separator + format);
            System.out.println("存放的文件夹: " + readPath);
            System.out.println("存放文件的绝对路径: " + readPath.getAbsolutePath());
            // 判断文件夹是否存在
            if (!readPath.isDirectory()) { 
                // 创建文件夹
                readPath.mkdirs();
            }
    
            // 文件真实的保存路径
            File file = new File(readPath.getAbsolutePath() + File.separator + newFileName);
            try { 
                multipartFile.transferTo(file);
    
                // 获取存储路径
                String filePath = getUploadPath(request, format + "/" + newFileName);
                map.put("path", filePath);
            } catch (IOException e) { 
                e.printStackTrace();
                map.put("msg", "上传失败");
            }
    
            return map;
        }
    }