Question

I want to have an application which parses various RSS feeds and send the information to a remote server. The information is sent in xml format via http. At first I tried to deploy this application on my own server, so I send the xml using the method shown in this tutorial by Java Tips. Here is my code which is replicated from the example:

First Method

    String strURL = "http://localhost/readme/readme_xml";
    String strXMLFilename = "output.xml";
    File input = new File(strXMLFilename);


    PostMethod post = new PostMethod(strURL);
    post.setRequestEntity(new InputStreamRequestEntity(
            new FileInputStream(input), input.length()));
    post.setRequestHeader(
            "Content-type", "text/xml; charset=ISO-8859-1");
    HttpClient httpclient = new HttpClient();
    try {

        int result = httpclient.executeMethod(post);            
        System.out.println("Response status code: " + result);            
        System.out.println("Response body: ");
        System.out.println(post.getResponseBodyAsString());            
    } finally {
        post.releaseConnection();
    }

This works perfectly (I even tested using a remote server outside the localhost). Then, somehow I cant use my own server to deploy this application, so I decided to migrate to Google Apps Engine. One thing about it, as we know it, is that not all libraries are allowed in the environment. So I try another method shown in ExampleDepot.com (I can’t find where the exact url though) as below:

Second Method

try {
           /* fill up this url with the remote server url */
            URL url = new URL("http://localhost/readme/readme_xml");
            FileReader fr = new FileReader("output.xml");
            char[] buffer = new char[1024*10];
            int len = 0;
            if ((len = fr.read(buffer)) != -1){
            /* send http request to remote server */
                URLConnection conn = url.openConnection();
                conn.setRequestProperty("Content-Type","text/xml;charset=ISO-8859-1"); /* need to specify the content type */
                conn.setDoOutput(true);
                conn.setDoOutput(true);
                PrintWriter pw = new PrintWriter(conn.getOutputStream());
                pw.write(buffer, 0, len);
                pw.flush();
                /* receive response from remote server*/
                BufferedReader bf = new BufferedReader(new InputStreamReader(conn.getInputStream()));
                String input = null;
                while ((input = bf.readLine()) != null){
                    System.out.println(input);
                }
            }

        } catch (MalformedURLException e) {
                e.printStackTrace();
        } catch (FileNotFoundException e) {
                e.printStackTrace();
        } catch (IOException e) {
                e.printStackTrace();
        }
    }

The second method though, doesn’t work and gives the following error (I use SimpleXMLElement (php) object to parse xml in the remote hosting):

Error message from remote server

Here’s the php code from the remote server (In here, I just want the SimpleXMLElement to parse the xml without doing anything else fancy for now)

$xml = new SimpleXMLElement('php://input', NULL, TRUE);
   foreach ($xml -> attributes() as $name => $val){
   echo "[".$name."] = ".$val."\n";
   }

I thought the cause of this problem is the malfunction xml file (because the eclipse IDE indicates there’s error of “invalid byte 1 of 1-byte utf-8 sequence”). Then I use the same exact input xml file to the first method, but it still works perfectly.

So is there any adjustment that I need to make to the second method? Or is there any other method that I can use to send xml file to remote server? Let me know if I need to add some other details. Thanks for your help.

---

NOTE: I actually solved this problem by using the solution given in the comments. I didn’t use approaches suggested in the answers, even though those answers are pretty useful. So, I didn’t select the best answer out of those answers given. Nonetheless, I still appreciate all of your helps, thus deserve my upvote. Cheers!

Answer 1

I guess you need to change the content type to multipart/form-data. See an already answered question in detailed. The file upload is discussed at the bottom of this example