java – Spring 3.0 MultipartFile上传

我正在将Java Web应用程序转换为Spring框架,并对我在文件上载时遇到的问题提出一些建议.原始代码是使用org.apache.commons.fileupload编写的.

> Spring MultipartFile是否包装了org.apache.commons.fileupload,或者我可以从我的POM文件中排除这种依赖关系？
>我见过以下例子：

@RequestMapping(value = "/form", method = RequestMethod.POST)
public String handleFormUpload(@RequestParam("file") MultipartFile file) {

    if (!file.isEmpty()) {
        byte[] bytes = file.getBytes();
        // store the bytes somewhere
       return "redirect:uploadSuccess";
    } else {
        return "redirect:uploadFailure";
    }
}

最初我试图遵循这个例子,但总是得到一个错误,因为它找不到这个请求参数.所以,在我的控制器中,我做了以下事情：

@RequestMapping(value = "/upload", method = RequestMethod.POST)
public @ResponseBody
ExtResponse upload(HttpServletRequest request, HttpServletResponse response)
{
   // Create a JSON response object.
   ExtResponse extResponse = new ExtResponse();
   try {
       if (request instanceof MultipartHttpServletRequest)
       {
           MultipartHttpServletRequest multipartRequest =
                        (MultipartHttpServletRequest) request;
           MultipartFile file = multipartRequest.getFiles("file");
           InputStream input = file.getInputStream();
           // do the input processing
           extResponse.setSuccess(true);
        }
    } catch (Exception e) {
        extResponse.setSuccess(false);
        extResponse.setMessage(e.getMessage());
    }
    return extResponse;
}

它正在发挥作用.如果有人能告诉我为什么@RequestParam不适合我,我会很感激.顺便说一句,我有

    <bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="maxUploadSize" value="2097152"/>
    </bean>

在我的servlet上下文文件中.

解决方法:

> spring不依赖于commons-fileupload,所以你需要它.如果不存在,春天将使用其内部机制
>您应该将MultipartFile作为方法参数传递,而不是@RequestParam(..)

标签：java,spring,multifile-uploader
来源： https://codeday.me/bug/20190902/1789009.html