Java 用于处理HttpClient进行的文件上载的服务器代码

我有一个Java HttpClient，它执行以下代码：

HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost("http://exampleutl.com/upload/");

File file = new File("C:/src_path/binary.doc");

MultipartEntityBuilder builder = MultipartEntityBuilder.create();

builder.setMode(HttpMultipartMode.STRICT);

FileBody fileBody = new FileBody(file); //image should be a String
builder.addPart("file", fileBody);
post.setEntity(builder.build());

client.execute(post);

我无法确定映射到/upload/path的服务器方法应该是什么样子

接受此文件上载请求的服务器是Spring 4.0。大概是这样的：

@RequestMapping(method = RequestMethod.POST, value = "/upload/")
public @ResponseBody String saveUpload(UploadDto dto) throws IOException,ServletException {
    File file = new File("C:/dest_path/" + dto.getFile().getOriginalFilename());
    FileUtils.writeByteArrayToFile(file, dto.getFile().getBytes());
    return "success";
}

@RequestMapping(method = RequestMethod.POST, value = "/upload/")
public @ResponseBody String saveUpload(@RequestParam("file") final MultipartFile mpf) throws IOException, ServletException, FileUploadException {
    File file = new File("C:/dest_path/" + mpf.getOriginalFilename());
    FileUtils.writeByteArrayToFile(file, mpf.getBytes());

    return "success";
}

上面的服务器方法由client.execute（）调用，但UploadDto为空。 以下是上传到：

public class UploadDto {
    private MultipartFile file;

    public MultipartFile getFile() {
        return file;
    }

    public void setFile(MultipartFile file) {
        this.file = file;
    }
}

---

任何帮助都将不胜感激

您似乎在SpringServlet上下文中缺少了一个

MultipartResolver

bean。差不多

@Bean
public MultipartResolver multipartResolver() {
    CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver();
    return multipartResolver;
}

---

您正在将请求发送到

HttpPost post = new HttpPost("http://exampleutl.com/upload/");

假设您的上下文路径是ROOT，即空的，您的处理程序方法应该映射到

/upload

@RequestMapping(method = RequestMethod.POST, value = "/upload")

---

最终的答案是服务器方法应该如下所示：

@RequestMapping(method = RequestMethod.POST, value = "/upload/")
public @ResponseBody String saveUpload(UploadDto dto) throws IOException,ServletException {
    File file = new File("C:/dest_path/" + dto.getFile().getOriginalFilename());
    FileUtils.writeByteArrayToFile(file, dto.getFile().getBytes());
    return "success";
}

@RequestMapping(method = RequestMethod.POST, value = "/upload/")
public @ResponseBody String saveUpload(@RequestParam("file") final MultipartFile mpf) throws IOException, ServletException, FileUploadException {
    File file = new File("C:/dest_path/" + mpf.getOriginalFilename());
    FileUtils.writeByteArrayToFile(file, mpf.getBytes());

    return "success";
}

正如Sotirios Delimanois所提到的，多部件解析器确实也是解决方案的必要组成部分：

@Bean
public MultipartResolver multipartResolver() {
    CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver();
    return multipartResolver;
} 

---

上传的dto是空的

是什么意思？@SotiriosDelimanolis我的意思是说dto.getFile（）是空的。你是对的，谢谢你注意到这个错误。不幸的是，这并不能解决问题。我已经编辑了这个问题来解决这个变化，并添加了更多的信息。@vanceagle您的上下文中似乎缺少了一个

MultipartResolver

bean。没有

多部分解析器

，Spring无法正确处理请求。