Create empty file using Document List API 3.0 - google-drive-api

Question

I am developing a feature which need to create a new empty file(not document) to Google drive, now I am using document list API 3.0 and I am referring to the document: https://developers.google.com/google-apps/documents-list/#uploading_a_new_document_or_file_with_both_metadata_and_content.
I will upload a zero byte file to the Google drive to generate the empty file.
Now I have a problem during request step 1 and request step 2. After the first Post[resumable-create-media link] request I successfully got the upload location. Then when I request put method to the location, I got a 404 not found error. All of the requests have "GData-Version: 3.0" and "Authorization: accessToken" headers.
I searched a lot from the forum and figured out how to create empty document but could not figure out how to create empty file. Here is my code, could anybody help to see which part is wrong? Thanks in advance.
private final static String PARAM_CONTENT_TYPE = "Content-Type";
private final static String PARAM_UPLOAD_LENGTH = "X-Upload-Content-Length";
private final static String PARAM_UPLOAD_TYPE = "X-Upload-Content-Type";
private final static String CONTENT_TYPE_XML = "application/atom+xml";
private final static String URI_RESUMABLE_RESOURCE = "https://docs.google.com/feeds/upload/create-session/default/private/full";
private final static String ENTITY_NEW_FILE = "<?xml version=\"1.0\" encoding=\"UTF-8\"?><entry xmlns=\"http://www.w3.org/2005/Atom\" "
+ "xmlns:docs=\"http://schemas.google.com/docs/2007\"><title>{0}</title></entry>";
#Override
public boolean createNewFile() throws IOException {
String uri = null;
if (ROOT.equals(parentResourceId))
uri = URI_RESUMABLE_RESOURCE;
else
uri = URI_RESUMABLE_RESOURCE + "/%3A" + parentResourceId + "/contents";
try {
StringEntity entity = new StringEntity(MessageFormat.format(ENTITY_NEW_FILE, getName()), Constants.ENCODING);
Map<String, String> headers = new HashMap<String, String>();
headers.put(PARAM_CONTENT_TYPE, CONTENT_TYPE_XML);
headers.put(PARAM_UPLOAD_LENGTH, "0");
headers.put(PARAM_UPLOAD_TYPE, "text/plain");
Map<String, String> params = new HashMap<String, String>();
params.put("convert", "false");
HttpResponse response = helper.execMethodAsResponse(uri, new PostMethod(entity), headers, params);
String location = null;
if ((location = response.getFirstHeader("Location").getValue()) != null) {
headers = new HashMap<String, String>();
headers.put(PARAM_CONTENT_TYPE, "text/plain");
headers.put("Content-Range", "bytes 0-0/0");
//FIXME: Problem occurs here, this put invocation will return 404 not found error.
JsonObject obj = helper.execMethodAsJson(location, new PutMethod(new ByteArrayEntity(new byte[0])), headers, null);
if (obj != null) {
decorateFile(this, obj.get("entry").getAsJsonObject());
return true;
}
}
} catch (UnsupportedEncodingException e) {
}
return false;
}

Answer 1

The easiest way to create an empty file on Google Drive is to use the Google Drive API v2 and send a service.files.insert(File content) request.
You can use the Java sample from the Reference Guide and edit it to not include a MediaContent: https://developers.google.com/drive/v2/reference/files/insert

Answer 2

I have figured out the problem, according to this link: Google Documents List API file upload 400 response
The second put request does not need any additional headers such as "GData-Version: 3.0" and "Authorization: Bearer ****", etc. The only thing need to do is new a put request with the location URI, then it will return response with 201 status code.
Thanks all.