Java Restful web服务方法消费MultiPart数据抛异常

Question

我正在尝试将图像从 Android 设备上传到服务器。正在调用我的 Web 服务方法，但它抛出一些异常。我尝试在网上搜索数小时，但没有找到任何解决方案。我是第一次使用 multipart。我已经改变了我的网络服务方法。[编辑]这是我的安卓客户端代码

    protected Boolean doInBackground(String... urls) {
      try{
          URL urlImage = new URL("http://10.0.2.2:8080/LostLove_services/love/Recipe/coverpic");
      HttpURLConnection urlConnectionImage = (HttpURLConnection) urlImage.openConnection();

    ImageButton coverImage = (ImageButton)findViewById(R.id.CoverPic);

     Bitmap bitmap = ((BitmapDrawable)coverImage.getDrawable()).getBitmap();


             urlConnectionImage.setUseCaches(false);
              urlConnectionImage.setDoOutput(true);
             urlConnectionImage.setDoInput(true);

            urlConnectionImage.setRequestMethod("POST");
            urlConnectionImage.setRequestProperty("Connection", "Keep-Alive");
            urlConnectionImage.setRequestProperty("Cache-Control", "no-cache");
           urlConnectionImage.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + this.boundary);
          DataOutputStream request = new DataOutputStream(urlConnectionImage.getOutputStream());

           request.writeBytes(this.twoHyphens + this.boundary + this.crlf);
                        request.writeBytes("Content-Disposition: form-data; name=\"" + this.attachmentName + "\";filename=\"" + this.attachmentFileName + "\"" + this.crlf);
                        request.writeBytes(this.crlf);
                     /*   byte[] pixels = new byte[bitmap.getWidth() * bitmap.getHeight()];
                        for (int i = 0; i < bitmap.getWidth(); ++i) {
                            for (int j = 0; j < bitmap.getHeight(); ++j) {
                                //we're interested only in the MSB of the first byte,
                                //since the other 3 bytes are identical for B&W images
                                pixels[i + j] = (byte) ((bitmap.getPixel(i, j) & 0x80) >> 7);
                            }
                        }
        */
 ByteArrayOutputStream bos = new ByteArrayOutputStream();
               bitmap.compress(Bitmap.CompressFormat.PNG, 0 /*ignored for PNG*/, bos);
               byte[] bitmapdata = bos.toByteArray();

              // Log.d("pixel size",pixels.clone().toString());
             //   Log.d("real size",Integer.toString(pixels.length));
                request.write(bitmapdata);
                                             request.writeBytes(this.crlf);
                        request.writeBytes(this.twoHyphens + this.boundary + this.twoHyphens + this.crlf);
                        request.flush();
                        Log.d("imageout",Integer.toString(urlConnectionImage.getResponseCode()));
                        request.close();
                                            switch (urlConnection.getResponseCode()) {
                            case HttpURLConnection.HTTP_OK:

                               return true;

                            default:

                                return false; // abort

                        }

                        // urlConnection.connect();

                    }
                    catch (Exception e)
                    {
                        Log.d("exeJsonPublish",e.toString());
                        return false;
                    }

                }

这是我的网络服务方法[已编辑]。我在缓冲图像中得到空值。

   @Path("/coverpic") 
     @POST
    // @Consumes("multipart/form-data")

     public String retrieveImage(FormDataMultiPart multipart)
     {
        Iterator it =  multipart.getFields().keySet().iterator();
        //System.out.println(it.next());
        FormDataBodyPart body = multipart.getField("bitmap");
        InputStream ins = ((BodyPartEntity )body.getEntity()).getInputStream();
        String uploadedFileLocation = "E:\\torr\\A.bmp" ;
        if(ins == null)
            System.out.println("is null");
      // writeToFile(ins, uploadedFileLocation);
        try {

            BufferedImage bi = ImageIO.read(ins);
            if(bi==null)
                System.out.println("bi is null");
        } catch (Exception e) {
            // TODO Auto-generated catch block
            //e.printStackTrace();
            System.out.println("exec is "+e);
        }
    //  System.out.println(multipart.getFields().keySet().iterator());
        /*try {
              InputStream source = ins;

            //BufferedImage bi = ImageIO.(source);
              BufferedImage bi = ImageIO.read(source);
             File file = new File("E:\\aditya.bmp");
             if (file.isDirectory()) {
                    ImageIO.write(bi, "bmp", file);
                  } else {
                    file.mkdirs();
                    ImageIO.write(bi, "bmp", file);
                  }

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }*/



         System.out.println("in retrieveImage"+ multipart.getBodyParts());
         return null;
     }

我已经更正了我的代码。现在它正在工作。在 android doInBackground 方法中未正确创建位图。

Answer 1

您可以使用 FormDataMultiPart

@POST
@Path("/coverpic")
@Consumes(MediaType.MULTIPART_FORM_DATA)
public Response uploadFile(FormDataMultiPart multiPart){
     FormDataBodyPart body = multiPart.getField(<your fieldname>);
     InputStream ins = ((BodyPartEntity) body.getEntity()).getInputStream();
     ///.....
     ///.....
     return Response.status(200).entity(output).build();

}

请检查您的字段名称“file”是否真的出现在 multipart 中，否则循环遍历 multiPart 并使用获取所有字段名称

multiPart.getFields().keySet().iterator()

你必须使用多部分依赖

<dependency>
    <groupId>com.sun.jersey.contribs</groupId>
    <artifactId>jersey-multipart</artifactId>
    <version>1.18.3</version>
</dependency>
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.3.1</version>
</dependency>