spring boot 文件上传下载

ゞ浴缸里的玫瑰 2022-05-03 06:28 177阅读 0赞

1、在application.properties中添加文件上传的配置信息

在1.x版本中application.properties中的配置信息如下

#文件上传配置
    spring.http.multipart.maxFileSize=50Mb
    spring.http.multipart.maxRequestSize=50Mb

在2.x版本中application.properties的配置如下，我们这里使用2.x的配置方式

#文件上传配置
    spring.servlet.multipart.maxFileSize=50Mb
    spring.servlet.multipart.maxRequestSize=50Mb

从1.x到2.x，配置有点小的变动，spring.http.multipart变更为spring.servlet.multipart，大家在使用的时候注意一下

2、在application.properties中自定义文件上传路径，后面我们通过@Value注解方式获取

#自定义配置-文件上传路径 上传到当前项目的files文件夹下
    self.file.uploadPath=${user.dir}/files

3、编写文件上传下载接口：FileController.java

package com.ldy.bootv2.demo.controller;
    
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.InputStream;
    import java.io.OutputStream;
    
    import javax.servlet.http.HttpServletResponse;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.util.StringUtils;
    import org.springframework.web.bind.annotation.PostMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    import org.springframework.web.multipart.MultipartFile;
    
    import io.swagger.annotations.Api;
    import io.swagger.annotations.ApiImplicitParam;
    import io.swagger.annotations.ApiOperation;
    import io.swagger.annotations.ApiParam;
    
    @RestController
    @Api(tags = "文件上传下载接口-API")
    @RequestMapping(value = "/file")
    public class FileController {
    
    	private static Logger logger = LoggerFactory.getLogger(FileController.class);
    
    	/**
    	 * 文件存放路径，配置在application.properties文件中
    	 */
    	@Value(value = "${self.file.uploadPath}")
    	private String uploadPath;
    
    	@PostMapping("/upload")
    	@ApiOperation("文件上传接口")
    	public String upload(@ApiParam(value = "文件", required = false) final MultipartFile file) {
    		if (null == file) {
    			logger.error("文件上传失败,文件不能为空");
    			return "error";
    		}
    
    		File dir = new File(uploadPath);
    		if (!dir.exists()) {
    			dir.mkdirs();
    		}
    	
    		File saveFile = new File(uploadPath, file.getOriginalFilename());
    		
    		try {
    			// 保存到指定路径
    			file.transferTo(saveFile);
    			// TODO 将上传的文件信息保存到数据库
    		} catch (Exception e) {
    			logger.error("文件上传失败,原因：", e);
    			return "error";
    		}
    
    		logger.info("文件上传成功，fileName = " + file.getOriginalFilename());
    		return "success";
    	}
    
    	
    	
    	@PostMapping("/download")
    	@ApiOperation("文件下载接口")
    	@ApiImplicitParam(name = "fileName", value = "文件名称", required = true, dataType = "String")
    	public String download(HttpServletResponse response,@RequestParam String fileName) {
    		if (StringUtils.isEmpty(fileName)) {
    			logger.error("文件下载失败,原因：文件名不能为空");
    			return "error";
    		}
    		try {
    			File file = new File(uploadPath + "/" + fileName);
    			response.setCharacterEncoding("utf-8");
    			response.setContentType("multipart/form-data");
    			fileName = new String(fileName.getBytes(), "ISO-8859-1");
    			response.setHeader("Content-Disposition", "attachment;fileName=" + fileName);
    			InputStream inputStream = new FileInputStream(file);
    			OutputStream os = response.getOutputStream();
    			byte[] b = new byte[1024];
    			int length;
    			while ((length = inputStream.read(b)) > 0) {
    				os.write(b, 0, length);
    			}
    			inputStream.close();
    		} catch (Exception e) {
    			logger.error("文件下载失败,原因：", e);
    			return "error";
    		}
    
    		logger.info("文件下载成功，fileName = " + fileName);
    		return "success";
    	}
    
    }

4、启动项目，通过swagger页面测试接口，swagger的集成请查看：[https://blog.csdn.net/LDY1016/article/details/83415640][https_blog.csdn.net_LDY1016_article_details_83415640]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70][]

（1）文件上传测试

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70 1][]

选择文件后点击“Execute”按钮

（2）文件下载测试

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70 2][]

输入文件名称后点击“Execute”按钮

源码下载地址：[https://pan.baidu.com/s/1Z771VDiuabDBJJV445xLeA\#list/path=%2Fspring%20boot%202.x%20%E4%BB%A3%E7%A0%81][https_pan.baidu.com_s_1Z771VDiuabDBJJV445xLeA_list_path_2Fspring_20boot_202.x_20_E4_BB_A3_E7_A0_81]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70 3][]

[https_blog.csdn.net_LDY1016_article_details_83415640]: https://blog.csdn.net/LDY1016/article/details/83415640
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70]: /images/20220503/d4a4242935ab4e9db3df778edc3c8f35.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70 1]: /images/20220503/cb40afd66a31497a95be3700e7132a7b.png
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[https_pan.baidu.com_s_1Z771VDiuabDBJJV445xLeA_list_path_2Fspring_20boot_202.x_20_E4_BB_A3_E7_A0_81]: https://pan.baidu.com/s/1Z771VDiuabDBJJV445xLeA#list/path=%2Fspring%20boot%202.x%20%E4%BB%A3%E7%A0%81
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0xEWTEwMTY_size_27_color_FFFFFF_t_70 3]: /images/20220503/279ab98e487c4f479685349324db4435.png