多部分请求获取错误代码400 java

我正在使用多功能请求Android中的web服务，发送的请求是：

POST / HTTP/1.1
connection: Keep-Alive
enctype: multipart/form-data
content-type: multipart/form-data;charset=UTF-8;boundary=--===1487292689114===
accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
accept-encoding: gzip, deflate, br
accept-language: es-419,es;q=0.8,en-GB;q=0.6,en;q=0.4
cache-control: max-age=0
upgrade-insecure-requests: 1
user-agent: Dalvik/1.6.0 (Linux; U; Android 4.4.4; 5042A Build/KTU84P)
host: 192.168.10.171:8080
content-length: 990
payload: ----===1487292689114===
Content-Disposition: form-data; name="new_id"

171
----===1487292689114===
Content-Disposition: form-data; name="file"; filename="IMG_20170216_195118.jpg"
Content-Type: image/jpeg
Content-Transfer-Encoding: binary

����
(
----===1487292689114===--

这是服务：

@POST
    @Path("/reportNewImage")
    @Consumes(MediaType.MULTIPART_FORM_DATA+"; charset=UTF-8")
    @Produces(MediaType.TEXT_PLAIN)
    public Response setImage(
            @FormDataParam("new_id") String new_id,
            @FormDataParam("file") InputStream uploadedInputStream,
            @FormDataParam("file") FormDataContentDisposition fileDetail, @Context HttpHeaders headers) {
        ...
    }

但是，当通过java android代码建立连接时，我收到了相同的错误。当我从html表单建立连接时，结果是成功的。请帮帮我，原因是什么

编辑：

使用html表单发出的请求：

POST / HTTP/1.1
Host: example.com
Connection: keep-alive
Content-Length: 6564
Cache-Control: max-age=0
Origin: http://localhost
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/55.0.2883.87 Chrome/55.0.2883.87 Safari/537.36
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryNt8QJSIDDDgznij8
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Referer: http://localhost/form.html
Accept-Encoding: gzip, deflate, br
Accept-Language: es-419,es;q=0.8,en-GB;q=0.6,en;q=0.4

------WebKitFormBoundaryNt8QJSIDDDgznij8
Content-Disposition: form-data; name="new_id"

109
------WebKitFormBoundaryNt8QJSIDDDgznij8
Content-Disposition: form-data; name="file"; filename="apple.jpg"
Content-Type: image/jpeg

����JFIFHH��C
...
                     �������1s�����K�"T�I)���ti6>�d
����
------WebKitFormBoundaryNt8QJSIDDDgznij8--

这是httpURLConnection Android：

    URL url = new URL(requestURL);
            httpConn = (HttpURLConnection) url.openConnection();
            httpConn.setRequestMethod("POST");
            httpConn.setUseCaches(false);
            httpConn.setDoOutput(true); // indicates POST method
            httpConn.setDoInput(true);
            httpConn.setRequestProperty("Content-Type",
                    "multipart/form-data; boundary=" + boundary);
            outputStream = httpConn.getOutputStream();
            writer = new PrintWriter(new OutputStreamWriter(outputStream, charset),
                    true);
writer.flush();
writer.close();
        // checks server's status code first
        int status = httpConn.getResponseCode();
        if (status == HttpURLConnection.HTTP_OK) {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    httpConn.getInputStream()));
            String line = null;
            while ((line = reader.readLine()) != null) {
                response.append(line);
            }
            reader.close();
            httpConn.disconnect();
        } else {
            throw new IOException("Server returned non-OK status: " + status);
        }

编辑2:

我发现只有在编译这一行时才会出现错误：

httpConn.setRequestProperty("Content-Type",
                        "multipart/form-data; boundary=" + boundary);

---

否则错误代码为415，因为没有定义

内容类型
标题。
问题在于边界。我在文档中发现边界可以由这组字符组成：

多部分内容类型的唯一必需参数是
边界参数，由一组字符中的1到70个字符组成
通过电子邮件网关已知的字符非常健壮，而不是
以空白结束。（如果边界似乎以白色结尾
空格，则必须假定空白是由
网关，并应删除。）它由
下列BNF：

边界：=0*69 bcharsnospace

bchars:=bcharsnospace/“”

bcharsnospace:=数字/ALPHA/“'”/“（“/”/“/“/”/“+”/“”
/ "," / "-" / "." / "/" / ":" / "=" / "?"

然而，自从我删除“=”字符后，一切都开始正常工作

旧联邦议院：--==1487292689114===

新边界：--X1487292689114x
它还说了什么？请求错误，没有进一步的详细信息？您能在服务器端设置一个断点吗？@efekctive我在JAX-RS中设置了一个过滤器，在处理servlet之前打印头和负载，但我无法获得更多信息，因为servlet会立即拒绝请求。你想要什么信息？你能在servlet处理之前比较两个请求吗？当然，看看版本。我尝试添加标题，但仍然不起作用。java android HttpURLConnection请求中没有添加Referer和Origin。