java - 使用 RestTemplate 时如何在分段上传中设置文件的内容类型(来自休息客户端)

Question

我尝试上传的文件将始终是 xml 文件。我想将内容类型设置为 application/xml 这是我的代码:

         MultiValueMap<String, Object parts = new LinkedMultiValueMap<String,
         Object(); parts.add("subject", "some info"); 
         ByteArrayResource xmlFile = new    ByteArrayResource(stringWithXMLcontent.getBytes("UTF-8")){
                 @Override
                 public String getFilename(){
                     return documentName;
                 }             
             };

     parts.add("attachment", xmlFile);

//sending the request using RestTemplate template;, the request is successfull 
String result = template.postForObject(getRestURI(), httpEntity,String.class);      
//but the content-type of file is 'application/octet-stream'

原始请求如下所示:

    Content-Type:
    multipart/form-data;boundary=gbTw7ZJbcdbHIeCRqdX81DVTFfA-oteHHEqgmlz
    User-Agent: Java/1.7.0_67 Host: some.host Connection: keep-alive
    Content-Length: 202866

    --gbTw7ZJbcdbHIeCRqdX81DVTFfA-oteHHEqgmlz Content-Disposition: form-data;    name="subject" Content-Type: text/plain;charset=ISO-8859-1
    Content-Length: 19

    some info

    --gbTw7ZJbcdbHIeCRqdX81DVTFfA-oteHHEqgmlz Content-Disposition: form-data;   name="attachment"; filename="filename.xml" Content-Type:
    application/octet-stream Content-Length: 201402

    ....xml file contents here ..

文件的内容类型正在生成为“application/octet-stream”，而我希望它是“application/xml”如何设置文件的内容类型？

Answer 1

从这个链接中得到提示后，我想出了解决方案:

Making a multipart post request with compressed jpeg byte array with spring for android

解决方案是将 ByteArrayResource 放入具有所需 header 的 HttpEntity 中，并将 HttpEntity 添加到 Multivaluemap(而不是添加 ByteArrayResource 本身。)

代码:

Resource xmlFile = new ByteArrayResource(stringWithXMLcontent.getBytes("UTF-8")){
            @Override
            public String getFilename(){
                return documentName;
            }
        };
        HttpHeaders xmlHeaders = new HttpHeaders();
        xmlHeaders.setContentType(MediaType.APPLICATION_XML);
        HttpEntity<Resource> xmlEntity = new HttpEntity<Resource>(xmlFile, xmlHeaders);
        parts.add("attachment", xmlEntity);