SpringBoot2.X实现文件上传与下载

偏执的太偏执、 2024-03-27 19:00 16阅读 0赞

本例子基于spring-boot-2.1.6.RELEASE开发  
pom文件：

<parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.6.RELEASE</version>
            <relativePath/> 
        </parent>
        <dependencies>
            
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
                <exclusions>
                    <exclusion>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-starter-logging</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
         </dependencies>

springboot对于文件上传的yml配置

spring:
      servlet:
        multipart:
          max-file-size: 2MB #上传一个文件最大值 默认是1MB
          max-request-size: 20MB #上传多个文件最大值  默认是10MB

直接上代码

import org.springframework.http.MediaType;
    import org.springframework.util.StreamUtils;
    import org.springframework.web.bind.annotation.*;
    import org.springframework.web.multipart.MultipartFile;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.*;
    import java.net.URLEncoder;
    
    @RestController
    @RequestMapping(path = "/", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
    public class FileController {
        final String path = "D:\\tmp\\";
    
        final String fileName = "D:\\tmp\\你好.txt";
    
        //文件上传
        @PostMapping(path = "/upload")
        public String upload(@RequestParam("file") MultipartFile file, HttpServletResponse response) {
         //获取原始文件名
            String originalFilename = file.getOriginalFilename();
            File localFile = new File(path + originalFilename);
            try {
             //直接将文件拷贝到指定位置
                file.transferTo(localFile);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (localFile.exists()) {
                return "ok";
            } else {
                response.setStatus(HttpServletResponse.SC_FORBIDDEN);
                return "error";
            }
        }
    
        //批量文件上传
        @PostMapping(path = "/uploads")
        public String uploadFiles(@RequestParam("file") MultipartFile[] files, HttpServletResponse response) {
            boolean result = true;
            StringBuilder stringBuilder = new StringBuilder();
            for (MultipartFile file : files) {
             //获取原始文件名
                String originalFilename = file.getOriginalFilename();
                File localFile = new File(path + originalFilename);
                try {
                 //直接将文件拷贝到指定位置
                    file.transferTo(localFile);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                boolean exists = localFile.exists();
                if (!exists) {
                    result = false;
                    stringBuilder.append(file.getOriginalFilename()).append(" ");
                }
            }
            if (result) {
                return "ok";
            }
            response.setStatus(HttpServletResponse.SC_FORBIDDEN);
            return "upload fail, file name : " + stringBuilder.toString();
        }
    
        //文件下载
        @GetMapping("/download")
        public void downloadFile(HttpServletResponse response) {
            File file = new File(fileName);
            if (file.exists()) {
                try (FileInputStream fis = new FileInputStream(file);
                     BufferedInputStream bis = new BufferedInputStream(fis)) {
                    response.setContentType("application/force-download");
                    //保证下载时文件名为指定文件名，避免中文文件名乱码
                    response.addHeader("Content-Disposition", "attachment;fileName="
                            + URLEncoder.encode(file.getName(), "utf-8"));
                    OutputStream os = response.getOutputStream();
                    StreamUtils.copy(bis, os);
                } catch (Exception e) {
                    response.setStatus(HttpServletResponse.SC_FORBIDDEN);
                    e.printStackTrace();
                }
            }
        }
    }

测试上传单个文件

![图片][3302417f4c6dd819b2f3ed6e5b17a706.png]

测试上传多个文件

![图片][58891e24cb1ab2d1c242ddd7a2e757d1.png]

下载文件测试直接使用浏览器请求接口URL即可

对于通过SpringCloudZuul映射后的文件上传请求，在文件上传时请求的url中需要加上/zuul前缀才能保证中文不乱码

[3302417f4c6dd819b2f3ed6e5b17a706.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/13/ae20221e51f1464cb1ac065e5e88a0dd.png
[58891e24cb1ab2d1c242ddd7a2e757d1.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/13/5321093341334126bb3b0016fe773c1c.png