Develop Reference

Get size of files using Google drive API

I am trying to list files from google drive along with their sizes for my app & below is the how i tried getting the size
File file = service.files().get(file.getId()).setFields("size").execute();
file.getSize()
I came to know that the size obtained from this call is not right as google drive only populates file size for files apart from google docs, sheet Get size of file created on Google drive using Google drive api in android
Also I tried determining file's size by making http GET to
webContentLink & checking the Content-Length header like below
HttpURLConnection conn = null;
String url = "https://docs.google.com/a/document/d/1Gu7Q2Av2ZokZZyLjqBJHG7idE1dr35VE6rTuSii36_M/edit?usp=drivesdk";
try {
URL urlObj = new URL(url);
conn = (HttpURLConnection) urlObj.openConnection();
conn.setRequestMethod("HEAD");
conn.getInputStream();
System.out.println(conn.getContentLength());
} catch (IOException e) {
e.printStackTrace();
} finally {
conn.disconnect();
}
But in this case , the file size is not correct as it comes out be very large
Is there any way I can determine the file size ?

Found the solution to the problem. For files uploaded to google drive, file size can be determined with file.getSize() call. For Google apps files such as doc, spreadsheet etc file.getSize() will return null as they don't consumer any space in drive. So as a hacky way, I am exporting as a pdf & determining the size. Below is the code for that
try {
Drive service = new Drive.Builder(HTTP_TRANSPORT, JSON_FACTORY, credential)
.setApplicationName("xyz")
.build();
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
service.files().export(fileId, "application/pdf")
.executeMediaAndDownloadTo(outputStream);
int fileSize = outputStream.toByteArray().length;
} catch (Exception ex) {
}

How to upload multiple files in Play Framework using Java

Hi i have been trying to upload image file in Play Framework. I have been trying out with Java File Upload since morning but unable to do so. I have seen [JavaFileUpload][1] tutorial available on framework website. But i am still not successful. Here is my code which i am trying to run:
Http.MultipartFormData body = request().body().asMultipartFormData();
List<Http.MultipartFormData.FilePart> fileParts = body.getFiles();
for (Http.MultipartFormData.FilePart filePart : fileParts) {
String filename = filePart.getFilename();
File file = filePart.getFile(); //error comes on this line
if (filePart.getFilename().toLowerCase().endsWith(".png")) {
//saving here but how?
} else {
return badRequest("Invalid request, only PNGs are allowed.");
}
}
but problem is that whenever i try to get the file i am having this conversion error:
java.lang.Object cannot be converted to java.io.File
Anyone can guide me in the direction? if we see the official document there is no proper documentation on how to upload multiple files. If anyone can show me some website which can helps me in that direction that will be also helpful

I'm using Play 2.4 and
FilePart filePart = request().body().asMultipartFormData()
.getFile("myFileKey");
File file = filePart.getFile();
With Play 2.2 I used for multiple file uploads:
MultipartFormData mfd = request().body().asMultipartFormData();
List<FilePart> filePartList = mfd.getFiles();
FilePart filePart = filePartList.get(0);

So after lots of trouble i was able to figure out the answer to my question. Here i am going to post the answer so it helps other people searching the answer to the same problem i faced
The controller function call which will upload the files looks like this:
Http.MultipartFormData body = request().body().asMultipartFormData();
List<Http.MultipartFormData.FilePart> fileParts = body.getFiles();
for (Http.MultipartFormData.FilePart filePart : fileParts) {
if (filePart.getFilename().toLowerCase().endsWith(".png")) {
String filename = filePart.getFilename();
Files.write(Paths.get(filename + ".png"), readContentIntoByteArray((File) filePart.getFile()));
} else {
return badRequest("Invalid request, only PNGs are allowed.");
}
}
I am using a function call to read the content of the file into byte array and save them inside the file:
private static byte[] readContentIntoByteArray(File file) {
FileInputStream fileInputStream = null;
byte[] bFile = new byte[(int) file.length()];
try {
//convert file into array of bytes
fileInputStream = new FileInputStream(file);
fileInputStream.read(bFile);
fileInputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
return bFile;
}
Remember you can choose whatever the path you want to save the file at Paths.get(filename + ".png")

Automatically download file from URL

I am attempting to download a file automatically. I know the link as I have already parsed it from the RSS XML file. Is there a simple noob friendly way of doing this?
Since my previous edit I have been informed that as long as I keep the file name the same I will be able to do this this is the code I have so far (I should have mentioned previously that this is for a bukkit plugin however the plugin)
public void getFile (String url) {
try{
BufferedInputStream in = new BufferedInputStream(new
URL("http://dev.bukkit.org/media/files/706/595/Kustom-Warn.jar").openStream());
FileOutputStream fileOutputStream = new FileOutputStream(plugin.getDataFolder().getAbsolutePath() + "/KustomWarn.jar");
logger.severe(String.valueOf(plugin.getDataFolder().getAbsolutePath()));
BufferedOutputStream outputStream = new BufferedOutputStream(fileOutputStream,1024);
byte data[] = new byte[1024];
while(in.read(data,0,1024)>=0)
{
outputStream.write(data);
}
outputStream.close();
in.close();
}catch (Exception e){
logger.severe("Error: " + e.getMessage());
}
}

If you mean to copy a file from a site to a local file then you can use java.nio.file
Files.copy(new URL("http://host/site/filename").openStream(), Paths.get(localfile));

Use URL.openStream to open the stream and Java NIO (New I/O) to read efficiently.

Reading directly from Google Drive in Java

Please I need to read the content of a file stored in Google Drive programmatically. I'm looking forward to some sort of
InputStream is = <drive_stuff>.read(fileID);
Any help?
I'll also appreciate if I can write back to a file using some sort of
OutputStream dos = new DriveOutputStream(driveFileID);
dos.write(data);
If this sort of convenient approach is too much for what Drive can offer, please I'll like to have suggestions on how I can read/write to Drive directly from java.io.InputStream / OutputStream / Reader / Writer without creating temporary local file copies of the data I want to ship to drive. Thanks!

// Build a new authorized API client service.
Drive service = getDriveService();
// Print the names and IDs for up to 10 files.
FileList result = service.files().list()
.setPageSize(10)
.setFields("nextPageToken, files(id, name)")
.execute();
List<File> files = result.getFiles();
if (files == null || files.size() == 0) {
System.out.println("No files found.");
} else {
System.out.println("Files:");
for (File file : files) {
System.out.printf("%s (%s)\n", file.getName(), file.getId());
String fileId = file.getId();
Export s=service.files().export(fileId, "text/plain");
InputStream in=s.executeMediaAsInputStream();
InputStreamReader isr=new InputStreamReader(in);
BufferedReader br = new BufferedReader(isr);
String line = null;
StringBuilder responseData = new StringBuilder();
while((line = br.readLine()) != null) {
responseData.append(line);
}
System.out.println(responseData);
}
}
}

Please take a look at the DrEdit Java sample that is available on the Google Drive SDK documentation.
This example shows how to authorize and build requests to read metadata, file's data and upload content to Google Drive.
Here is a code snippet showing how to use the ByteArrayContent to upload media to Google Drive stored in a byte array:
/**
* Create a new file given a JSON representation, and return the JSON
* representation of the created file.
*/
#Override
public void doPost(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
Drive service = getDriveService(req, resp);
ClientFile clientFile = new ClientFile(req.getReader());
File file = clientFile.toFile();
if (!clientFile.content.equals("")) {
file = service.files().insert(file,
ByteArrayContent.fromString(clientFile.mimeType, clientFile.content))
.execute();
} else {
file = service.files().insert(file).execute();
}
resp.setContentType(JSON_MIMETYPE);
resp.getWriter().print(new Gson().toJson(file.getId()).toString());
}

Here's a (incomplete) snippet from my app which might help.
URL url = new URL(urlParam);
HttpURLConnection connection = (HttpURLConnection) url
.openConnection();
connection.setDoOutput(true);
connection.setRequestMethod("GET");
connection
.setRequestProperty("Authorization",
"OAuth "+accessToken);
String docText = convertStreamToString(connection.getInputStream());

Using google-api-services-drive-v3-rev24-java-1.22.0:
To read the contents of a file, make sure you set DriveScopes.DRIVE_READONLY when you do GoogleAuthorizationCodeFlow.Builder(...) in your credential authorizing method/code.
You'll need the fileId of the file you want to read. You can do something like this:
FileList result = driveService.files().list().execute();
You can then iterate the result for the file and fileId you want to read.
Once you have done that, reading the contents would be something like this:
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
driveService.files().get(fileId).executeMediaAndDownloadTo(outputStream);
InputStream in = new ByteArrayInputStream(outputStream.toByteArray());

How to write images, swf's, videos and anything else that is stored on a website to a file on my computer using streams

I'm trying to write a program that copies a website to my harddrive. This is easy enough to do just copying over the source and saving it as an html file, but In doing that you can't access any of the pictures, videos etc offline. I was wondering if there is a way to do this using an input/output stream and if so how exactly to do it...
Thanks so much in advance

If you have URL of the file to be downloaded then you can simply do it using apache commons-io
org.apache.commons.io.FileUtils.copyURLToFile(URL, File);
EDIT :
This code will download a zip file on your desktop.
import static org.apache.commons.io.FileUtils.copyURLToFile;
public static void Download() {
URL dl = null;
File fl = null;
try {
fl = new File(System.getProperty("user.home").replace("\\", "/") + "/Desktop/Screenshots.zip");
dl = new URL("http://example.com/uploads/Screenshots.zip");
copyURLToFile(dl, fl);
} catch (Exception e) {
System.out.println(e);
}
}