spring-boot上传文件MultiPartFile获取不到文件问题解决

it2022-05-05  135

1.现象是在spring-boot里加入commons-fileupload jar并且配置了mutilPart的bean,在upload的POST请求后,发现

multipartRequest.getFiles("file")=null,有点奇怪,查了文档资料才解决。 [java]  view plain  copy   <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">         <property name="maxUploadSize" value="104857600"/>         <property name="maxInMemorySize" value="4096"/>     </bean>  

2.原因是:spring-boot自带的org.springframework.web.multipart.MultipartFile和Multipart产生冲突,如果同时使用了MultipartResolver 和ServletFileUpload,就会在iter.hasNext()返回false.然后整个循环就跳出去了。整个问题产生的原因是Spring框架先调用了MultipartResolver 来处理http multi-part的请求。这里http multipart的请求已经消耗掉。后面又交给ServletFileUpload ,那么ServletFileUpload 就获取不到相应的multi-part请求。因此将multipartResolve配置去除,问题就解决了。

3. 单文件的话只需要一个变量即,多文件上传的话就将MultipartFile改为数组,然后分别上传保存即可。

 

[java]  view plain  copy   @RequestMapping(value="/multipleSave", method=RequestMethod.POST )      public @ResponseBody String multipleSave(@RequestParam("file") MultipartFile[] files){          String fileName = null;          String msg = "";          if (files != null && files.length >0) {              for(int i =0 ;i< files.length; i++){                  try {                      fileName = files[i].getOriginalFilename();                      byte[] bytes = files[i].getBytes();                      BufferedOutputStream buffStream =                               new BufferedOutputStream(new FileOutputStream(new File("/tmp/" + fileName)));                      buffStream.write(bytes);                      buffStream.close();                      msg += "You have successfully uploaded " + fileName";                  } catch (Exception e) {                      return "You failed to upload " + fileName + ": " + e.getMessage();                  }              }              return msg;          } else {              return "Unable to upload. File is empty.";          }      }  }  

4.spring-boot 配置上传文件和请求文件的最大值限制:直接在application.properties中multipart.maxFileSize=128KBmultipart.maxRequestSize=128KB

 

5. spring-boot-starter-web are already added as dependencies. To upload files with Servlet containers, you need to register aMultipartConfigElement class (which would be <multipart-config> in web.xml). Thanks to Spring Boot, everything is auto-configured for you! spring-boot-upload链接

转载于:https://www.cnblogs.com/panxuejun/p/7476192.html


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