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How to download and save Bitmap of animated webp?

When I am using webp files for animated sticker packs it get rejected but if use same files for static stickers it get excepted. After looking all the codes I came to know that this is the last point where those files becomes problematic. But don not know how to identify if webp files stays as animated webp after saving. Please share your thought.
ps: I am using these webp files for whatsapp sticker packs. there is flag "animated_sticker_pack". we have to tell whatsapp that this pack contains only animated webp with proper fomrat. If I set it false then sticker pack get added (let it be static or animated webp). But if I set that flag true then those animated webp get rejected for pack showing error that There's problem with this pack.... So it might be that frames are lesser then it required. It get accepted as static means it might have single frame only.
To avoid issues regarding file type,format,size and all I am using the sample files from WhatsApp sample app
Code:
public static void SaveImage(Bitmap finalBitmap, String name, String identifier) {
String root = path + "/" + identifier;
File myDir = new File(root);
myDir.mkdirs();
String fname = name;
File file = new File(myDir, fname);
if (file.exists()){
file.delete();
}
try {
// FileOutputStream
FileOutputStream out = new FileOutputStream(file);
// Bitmap.compress
finalBitmap.compress(Bitmap.CompressFormat.WEBP, 100, out);
// close
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
////////////////////Other methods before saving images
private Bitmap downloadImageBitmap(String sUrl, String sIdentifier, String sName) {
imageFileName = getLastBitFromUrl(sUrl).replace(".png", ".webp");
identifier = sIdentifier;
name = sName;
Bitmap bitmap = null;
try {
InputStream inputStream = new URL(sUrl).openStream(); // Download Image from URL
bitmap = BitmapFactory.decodeStream(inputStream); // Decode Bitmap
inputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
return bitmap;
}
#Override
protected Bitmap doInBackground(String... params) {
return downloadImageBitmap(params[0], params[1], params[2]);
}
protected void onPostExecute(Bitmap result) {
SaveImage(result, imageFileName, identifier);
}

You can download and save in doInBackground()
InputStream inputStream = new URL(sUrl).openStream(); // Download Image from URL
FileOutputStream out = new FileOutputStream(file);
Then make a loop where you read bytes in a buffer from input stream and write to output stream.
Don't forget to close all streams when done.

Writing with an OutputStream to a DocumentFile: data seem to be written but file ends up empty

The application KDE Connect allows remotely browsing an Android device from a desktop computer through SFTP. Since Android 4.4, developers don't have write permission to SD cards directly through the filesystem anymore. So I am trying to port the SFTP module using the Storage Access Framework (DocumentFile, etc.)
I am taking the permission with an Intent.ACTION_OPEN_DOCUMENT_TREE and FLAG_GRANT_WRITE_URI_PERMISSION and passing the context to my classes.
I am able to create new empty files, rename files and delete files on the SD card inside my class so I believe I am getting the necessary permissions. However, transferring a file results in an empty file (0 bytes) being created. I can see the transfer taking a certain time and a progress bar on the desktop side, so it doesn't just abort.
Here is the relevant part of the SftpSubsystem class from the Apache SSHD library (see doc here) with my own comments to explain what's going on:
public class SftpSubsystem implements Command, Runnable, SessionAware, FileSystemAware {
// This method receives a buffer from an InputStream and processes it
// according to its type. In this situation, it would also contain
// a block of the file being transferred (4096 bytes)
protected void process(Buffer buffer) {
int type = buffer.getByte();
switch (type) {
case WRITE:
FileHandle fh = getHandleFromString(buffer.getString());
long offset = buffer.getLong();
byte[] data = buffer.getBytes();
fh.write(data, offset);
break;
// other cases
}
}
// This class is a handle to a file (duh) with
// an OutputStream to write and InputStream to read
protected static class FileHandle {
SshFile file;
OutputStream output;
long outputPos;
InputStream input;
long inputPos;
// Method called inside process()
public void write(byte[] data, long offset) throws IOException {
if (output != null && offset != outputPos) {
IoUtils.closeQuietly(output);
output = null;
}
if (output == null) {
// This is called once at the start of the transfer.
// This is what I think I need to rewrite to make
// it work with DocumentFile objects.
output = file.createOutputStream(offset);
}
output.write(data);
outputPos += data.length;
}
}
}
The original implementation of createOutputStream() that I want to rewrite because RandomAccessFile doesn't work with DocumentFile:
public class NativeSshFile implements SshFile {
private File file;
public OutputStream createOutputStream(final long offset)
throws IOException {
// permission check
if (!isWritable()) {
throw new IOException("No write permission : " + file.getName());
}
// move to the appropriate offset and create output stream
final RandomAccessFile raf = new RandomAccessFile(file, "rw");
try {
raf.setLength(offset);
raf.seek(offset);
// The IBM jre needs to have both the stream and the random access file
// objects closed to actually close the file
return new FileOutputStream(raf.getFD()) {
public void close() throws IOException {
super.close();
raf.close();
}
};
} catch (IOException e) {
raf.close();
throw e;
}
}
}
One of the ways I tried to implement it:
class SimpleSftpServer {
static class AndroidSshFile extends NativeSshFile {
// This is the DocumentFile that is stored after
// create() created the empty file
private DocumentFile docFile;
public OutputStream createOutputStream(final long offset) throws IOException {
// permission check
if (!isWritable()) {
throw new IOException("No write permission : " + docFile.getName());
}
ParcelFileDescriptor pfd = context.getContentResolver().openFileDescriptor(docFile.getUri(), "rw");
FileDescriptor fd = pfd.getFileDescriptor();
try {
android.system.Os.lseek(fd, offset, OsConstants.SEEK_SET);
} catch (ErrnoException e) {
Log.e("SimpleSftpServer", "" + e);
return null;
}
return new FileOutputstream(fd, offset);
}
}
}
I also tried a simple (the offset is ignored but it's just a test):
public OutputStream createOutputStream(final long offset) throws IOException {
// permission check
if (!isWritable()) {
throw new IOException("No write permission : " + docFile.getName());
}
return context.getContentResolver().openOutputStream(docFile.getUri());
}
I also tried with a FileChannel and to flush and sync the FileOutputStream.
Any idea why I end up with an empty file?
EDIT: here is a small example of a test I did to just write a new file from an existing file. It works, but this is not what I actually want to do (see code above) but I thought I'd provide an example to show that I understand the basics of how to write to an OutputStream.
private void createDocumentFileFromFile() {
File fileToRead = new File("/storage/0123-4567/lady.m4a");
File fileToWrite = new File("/storage/0123-4567/lady2.m4a");
File dir = fileToWrite.getParentFile();
DocumentFile docDir = DocumentFile.fromTreeUri(context, SimpleSftpServer.externalStorageUri);
try {
DocumentFile createdFile = docDir.createFile(null, fileToWrite.getName());
Uri uriToRead = Uri.fromFile(fileToRead);
InputStream in = context.getContentResolver().openInputStream(uriToRead);
OutputStream out = context.getContentResolver().openOutputStream(createdFile.getUri());
try {
int nbOfBytes = 0;
final int BLOCKSIZE = 4096;
byte[] bytesRead = new byte[BLOCKSIZE];
while (true) {
nbOfBytes = in.read(bytesRead);
if (nbOfBytes == -1) {
break;
}
out.write(bytesRead, 0, nbOfBytes);
}
} finally {
in.close();
out.close();
}
} catch (IOException e) {
}
}

"When using ACTION_OPEN_DOCUMENT_TREE, your app gains access only to the files in the directory that the user selects. You don't have access to other apps' files that reside outside this user-selected directory.
This user-controlled access allows users to choose exactly what content they're comfortable sharing with your app."
This means, you can only read/write/delete the content/meta data of already existing files or in sub directories in the selected directory, the scope that the user accept to be "comfortable" with.
Actually the user granted permmision to a list of Uri's in this folder for ea file/sub directory there is seperate uri permmision.
Now for example if I will try to create new file in the selected Uri using DocumentFile Ill success but if i will try to outputatream new data to this file I will fail because the user did not grant permision to write to this newly created file.
He only granted to write in the directory path level, means create new file here.
So same happens when you try to move/transfer file to other path that does not have permission from the user.
Path can be folder or file and for ea new path the user needs to grant new access.
move file = new path
write to just created file = new path

Delete an image on java server

I am doing a project that consists of a java server and a web page. I'd like to do that when you delete an object from the web, the server deletes the image asociated with this object. The images of each object are stored inside the images folder inside the web folder. But when i try to delete an image in the server, it says that the file is used by another process,because the thread of the web server is using it (i use grizzly), so I an't delete it.
//save the image
private void saveImage(Eetakemon e){
String base64Image = e.getImage().split(",")[1];
byte[] imageBytes =
javax.xml.bind.DatatypeConverter.parseBase64Binary(base64Image);
File imageFile = new File("WEB\\images\\" + e.getName() + ".png");
try {
BufferedImage bufferedImage = ImageIO.read(new
ByteArrayInputStream(imageBytes));
ImageIO.write(bufferedImage, "png", imageFile);
}
catch(Exception ex){
ex.printStackTrace();
}
}
//delete the image
private void deleteImage(Eetakemon e){
try {
Files.deleteIfExists(Paths.get("WEB\\images\\" + e.getName() +
".png"));
}catch(Exception ex){
ex.printStackTrace();
}
}
The funcions are called inside the create and delete methods respectively
Thank you

You should use a separate folder in your filesystem with read/write access and keep your web server responsible for serving only static content, like static images, HTML,CSS and JS files.
To handle dynamic image files that can eventually be deleted during runtime keep the business logic in a separate service such as a REST API or a simple Servlet.
You can temporarily move the deleted images to a separate folder to be marked for deletion by a later scheduled batch job.
example of a service to delete an image:
public void removeFiles(List<String> fileNames) {
try {
String trashFolderLocation = ConfigurationManager.getInstance().getConfig().getImgFileTrashPath();
String uploadedFileLocation = ConfigurationManager.getInstance().getConfig().getFilePath();
FileUtil.moveFilesToFolder(uploadedFileLocation, trashFolderLocation, fileNames);
} catch(FileException e) {
logException(e);
}
}
In FileUtil:
public static boolean moveFilesToFolder(String locationFrom, String locationTo, List<String> fileNames) throws FileException {
try {
for (String fileName : fileNames) {
File afile = new File(locationFrom + fileName);
if (!afile.renameTo(new File(locationTo + fileName))) {
return false;
}
}
} catch (Exception e) {
throw new FileException(e);
}
return true;
}

You are experiencing a windows property of locking files that are used. You need to locate the process that are using the file and close the resource. This is your only viable option unless you are able to run on a system that doesn't lock files in use. Linux/Unix systems doesn't have this behaviour and they would allow you to delete the file even if it used.

Displaying Base64-Encoded String of raw PDF data using ThinkFree PDF Viewer

The problem:
I'm getting a Base64-Encoded String of raw PDF data from a web service (this data is housed in my String array pdfData). I have to use this data display the PDF in a PDF viewer (I happen to be using the included 'ThinkFree PDF Viewer' since I'm working on an Android application, but lets generalize and say any PDF viewer will do). Note that I'm accessing the 0th element of this array just for testing purposes (to make sure I can at least pull up 1 PDF before writing the code to pull up all the PDFs).
The code is within a class. First the method createFile is called, then intentOpenPDF:
import org.apache.commons.codec.binary.Base64;
File file;
FileOutputStream outputStream;
private byte[] decodedContent;
private String[] pdfData;
private String[] pdfFileName;
public void createFile() {
decodedContent = Base64.decodeBase64(pdfData[0].getBytes());
try {
File path = new File(getFilesDir(), "PDFs");
if (!path.exists()) {
path.mkdirs();
}
file = new File(path, pdfFileName[0]);
outputStream = new FileOutputStream(file);
outputStream.write(decodedContent);
outputStream.close();
}
catch (FileNotFoundException ex) {
ex.printStackTrace();
}
catch (IOException ex) {
ex.printStackTrace();
}
finally {
// Make absolutely certain the outputStream is closed
try {
if (outputStream != null) {
outputStream.close();
}
}
catch (IOException ex) {
ex.printStackTrace();
}
}
}
public void intentOpenPDF() {
// Make sure the file exists before accessing it:
if (file.exists()) {
Uri targetUri = Uri.fromFile(file);
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(targetUri, "application/pdf");
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
}
}
The error:
Error opening file. It does not exist or cannot be read.
I have a break point set inside the conditional statement that checks if the file exists (within the intentOpenPDF method), and it IS passing this check.

The path produced by calling getFilesDir() leads a protected directory (file:///data/data/), where only files created with openFileOutput(String, int) are stored. I am not creating the file this way. The solution in my case is to use getExternalFilesDir(null).getAbsolutePath() instead, which will give you a path a directory internal to the application (/storage/emulated/0/Android/data/). No permissions are required to read or write to this path.

Considering your error message:
It does not exist or cannot be read.
as you verified it exists (first possible cause), it's certainly not readable (second possible cause).

java.io.FileNotFoundException when uploading a file from a JSP

I have coded a AJAX file upload feature in my application. It works perfectly when running it from my laptop. When I try the exact same file using the same app, but deployed on a jBoss server, I get the following exception:
2013-02-18 11:30:02,796 ERROR [STDERR] java.io.FileNotFoundException: C:\Users\MyUser\Desktop\TestFile.pdf (The system cannot find the file specified).
getFileData method:
private byte[] getFileData(File file) {
FileInputStream fileInputStream = null;
byte[] bytFileData = null;
try {
fileInputStream = new FileInputStream(file);
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
if (fileInputStream != null) {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
byte[] bytBuffer = new byte[1024];
try {
for (int readNum; (readNum = fileInputStream.read(bytBuffer)) != -1;) {
byteArrayOutputStream.write(bytBuffer, 0, readNum);
}
} catch (IOException e) {
e.printStackTrace();
}
bytFileData = byteArrayOutputStream.toByteArray();
}
return bytFileData;
}
Getting the file content in a variable (from the method above):
byte[] bytFileData = this.getFileData(file);
Making the file:
private boolean makeFile(File folderToMake, File fileToMake, byte[] bytFileData) {
Boolean booSuccess = false;
FileOutputStream fileOutputStream = null;
try {
if (!folderToMake.exists()) {
folderToMake.mkdirs();
}
if (!fileToMake.exists()) {
if (fileToMake.createNewFile() == true) {
booSuccess = true;
fileOutputStream = new FileOutputStream(fileToMake);
fileOutputStream.write(bytFileData);
fileOutputStream.flush();
fileOutputStream.close();
}
}
} catch (Exception e) {
e.printStackTrace();
booSuccess = false;
}
return booSuccess;
}
Any idea?
Thank you
Charles

It seems you're just passing the file path as part of the request to the server, not actually uploading the file, then attempting to use that file path to access the file.
That will work on your laptop because the code, when running locally, has access to your file system and will be able to locate the file. It won't work deployed on a server because it's an entirely separate machine, and as a result won't have access to your file system.
You'll need to modify your client-side (AJAX) code to actually upload the file, then modify your server-side code to use that uploaded file. Note that AJAX file uploads aren't generally possible - there are plugins for frameworks such as jQuery that provide this functionality using workarounds.
I'm not 100%, but I think proper AJAX file uploads may be possible using HTML5 features, but browser support for that is likely going to be pretty poor right now.