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Download file from API server using URLConnection in Kotlin

I want to download a file into my library using URLConnection.
The size of the picture stored in the server is about 16mb, but the size of the saved picture is 84B.
There seems to be an error while reading the buffer, can you tell me what kind of error it is?
binding.signDownloadBtn.setOnClickListener {
val userId = binding.userIdText.text.toString()
val filetype = "user"
val fileSeparation = "sign"
Thread {
val spec = "myurl/${userId}/${filetype}/${fileSeparation}"
val outputDir = Environment.getExternalStorageDirectory().toString() + "/" + Environment.DIRECTORY_DOWNLOADS
var `is`: InputStream? = null
var os: FileOutputStream? = null
try {
val url = URL(spec)
val conn = url.openConnection() as HttpURLConnection
conn.requestMethod = "GET"
conn.setRequestProperty("Content-Type", "application/json;utf-8")
conn.setRequestProperty("Accept", "application/json")
conn.setRequestProperty("token", user_token)
conn.setRequestProperty("sysCd", sysCd)
conn.connectTimeout = 1500
println("responseCode ${conn.responseCode}")
if (conn.responseCode == HttpURLConnection.HTTP_OK) {
var fileName = ""
val disposition = conn.getHeaderField("Content-Disposition")
val contentType = conn.contentType
if (disposition != null) {
val target = "filename="
val index = disposition.indexOf(target)
if (index != -1) {
fileName =
disposition.substring(index + target.length)
fileName =
fileName.replace("\"", "")
}
println("Content-Type = $contentType")
println("Content-Disposition = $disposition")
println("fileName = $fileName")
`is` = conn.inputStream
os = FileOutputStream(File(outputDir, fileName))
val BUFFER_SIZE = 4096
var bytesRead: Int
val buffer = ByteArray(BUFFER_SIZE)
while (`is`.read(buffer).also { bytesRead = it } != -1) {
os.write(buffer, 0, bytesRead)
}
os.close()
`is`.close()
}
println("File downloaded")
} else {
println("No file to download. Server replied HTTP code: ${conn.responseCode}")
}
conn.disconnect()
} catch (e: Exception) {
println("An error occurred while trying to download a file.")
e.printStackTrace()
try {
`is`?.close()
os?.close()
} catch (e1: IOException) {
e1.printStackTrace()
}
}
}.start()
}

How to zip folder and sub-folder using zip4j and outputstream

In the program that I am writing, I take the uri of the location to save the zip file from a user. Then, I try to zip the files and folders using zip4j library and outpustream in Android. I modified the code in this Stackoverflow answer and used zip4j instead. My modified code produces the zip file, however it is corrupted.
this is my code written in Kotlin:
class ZipBuilder {
private fun buildZipParameters(compressionMethod: CompressionMethod, compressionLevel: CompressionLevel,
encrypt: Boolean,
encryptionMethod: EncryptionMethod?,
aesKeyStrength: AesKeyStrength?
): ZipParameters? {
val zipParameters = ZipParameters()
zipParameters.compressionMethod = compressionMethod
zipParameters.compressionLevel = compressionLevel
return zipParameters
}
fun zipFileAtPath(sourcePath: String?, toLocation: ParcelFileDescriptor?): Boolean {
println("zipFileAtPath is called")
val BUFFER = 2048
val sourceFile = File(sourcePath!!)
val zipParameters = buildZipParameters(CompressionMethod.DEFLATE, CompressionLevel.NORMAL,
false, null, null)
try {
var origin: BufferedInputStream? = null
val desc = toLocation
val dest = FileOutputStream(desc!!.fileDescriptor)
val out = ZipOutputStream(BufferedOutputStream(dest))
if (sourceFile.isDirectory) {
zipParameters.rootFolderNameInZip = sourcePath
zipSubFolder(out, sourceFile, sourceFile.parent!!.length, zipParameters!!)
} else {
val data = ByteArray(BUFFER)
val fi = FileInputStream(sourcePath)
origin = BufferedInputStream(fi, BUFFER)
zipParameters!!.fileNameInZip = getLastPathComponent(sourcePath)
zipParameters.lastModifiedFileTime = sourceFile.lastModified()
out.putNextEntry(zipParameters)
var count: Int = 0
while (fi.read(data).also({ count = it }) != -1) {
out.write(data, 0, count)
}
}
out.close()
} catch (e: java.lang.Exception) {
e.printStackTrace()
return false
}
return true
}
#Throws(IOException::class)
private fun zipSubFolder(
out: ZipOutputStream, folder: File, basePathLength: Int, zipParameters: ZipParameters
) {
val BUFFER = 2048
val fileList = folder.listFiles()
var origin: BufferedInputStream
fileList?.forEach { file ->
if (file.isDirectory) {
zipSubFolder(out, file, basePathLength, zipParameters)
} else {
val data = ByteArray(BUFFER)
val unmodifiedFilePath = file.path
val relativePath = unmodifiedFilePath
.substring(basePathLength)
val fi = FileInputStream(unmodifiedFilePath)
origin = BufferedInputStream(fi, BUFFER)
zipParameters.fileNameInZip = relativePath
zipParameters.lastModifiedFileTime = file.lastModified()
out.putNextEntry(zipParameters)
var count: Int = 0
while (fi.read(data).also({ count = it }) != -1) {
out.write(data, 0, count)
}
origin.close()
}
}
}
fun getLastPathComponent(filePath: String): String? {
val segments = filePath.split("/").toTypedArray()
return if (segments.size == 0) "" else segments[segments.size - 1]
}
}
I would appreciate it if someone could tell me what could be the problem.

I guess you forgot to closeEntry() after writing date for that particular entry. You need to do out.closeEntry() after the while loop of writing data. Have a look at the example here.
while (fi.read(data).also({ count = it }) != -1) {
out.write(data, 0, count)
}
out.closeEntry() // --> close entry after writing data

MediaRecorder record audio in a loop

I'm developing a sound recognition system. I'm using a tensorflow model developed on python to convert MFCC values to labels. I'm using the MediaRecorder class to record the audio, and I'm doing it in a loop so I can be constantly getting microphone audio and then getting the label from the model. Here is the recording loop:
temp = 0;
while (true) {
audioPath = getApplicationContext().getFilesDir().getAbsolutePath();
audioPath += "/Recording" + temp + ".3gp";
audioFile = new File(audioPath);
mediaRecorder = new MediaRecorder();
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mediaRecorder.setOutputFile(audioPath);
try {
mediaRecorder.prepare();
} catch (IOException e) {
e.printStackTrace();
}
mediaRecorder.start();
sleep(2000);
if (!isRunning) {
mediaRecorder.stop();
return;
}
try {
int amplitude = mediaRecorder.getMaxAmplitude();
Log.d("volume", Integer.toString(amplitude));
//finished = false;
avgVolumeTask task = new avgVolumeTask();
task.execute(amplitude);
} catch (Exception e) {
Log.d("Exception in startMediaRecorder()", e.toString());
}
mediaRecorder.stop();
mediaRecorder.release();
soundRecognition task2 = new soundRecognition();
task2.execute();
audioFile.delete();
temp++;
}
This is the soundRecognition method:
private class soundRecognition extends AsyncTask<Integer, Integer, Long> {
#Override
protected Long doInBackground(Integer... level) {
float[] mfccValues = null;
Interpreter tflite = null;
float[][] labelProbArray = null;
try {
mfccValues = computeMFCC();
labelList = loadLabelList();
labelProbArray = new float[1][labelList.size()];
tflite = new Interpreter(loadModel());
} catch (IOException e) {
e.printStackTrace();
} catch (UnsupportedAudioFileException e) {
e.printStackTrace();
}
tflite.run(mfccValues, labelProbArray);
for (int i = 0; i < labelProbArray[0].length; i++) {
float value = labelProbArray[0][i];
//if (i == 1f){
//Log.d("Output at " + Integer.toString(i) + ": ", Float.toString(value));
//doAlert(i);
//}
}
return null;
}
}
The computeMFCC method is this:
public float[] computeMFCC() throws IOException, UnsupportedAudioFileException {
FileInputStream in2 = new FileInputStream(audioPath);
int i;
// InputStream to byte array
byte[] buf = IOUtils.toByteArray(in2);
in2.close();
i = Integer.MAX_VALUE;
// byte array to short array
short[] shortArr = new short[buf.length / 2];
ByteBuffer.wrap(buf).order(ByteOrder.LITTLE_ENDIAN).asShortBuffer().get(shortArr);
int count = 0;
while (count <= shortArr.length) { // Still have data to process.
for (int n = 0; n < nSubframePerBuf; n++) { // Process audio signal in ArrayList and shift by one subframe each time
int k = 0;
for (i = (n * frameShift); i < (n + 1) * frameShift; i++) {
subx[k] = shortArr[i];
k++;
}
subframeList.add(subx); // Add the current subframe to the subframe list. Later, a number of
}
count++;
}
// Need at least nSubframePerMfccFrame to get one analysis frame
x = extractOneFrameFromList(nSubframePerMfccFrame);
MFCC mfcc = new MFCC(samplePerFrm, 16000, numMfcc);
double[] mfccVals = mfcc.doMFCC(x);
float[] floatArray = new float[mfccVals.length];
for (i = 0 ; i < mfccVals.length; i++)
{
floatArray[i] = (float) mfccVals[i];
}
return floatArray;
}
And the doMFCC method is from a downloaded java file here:
https://github.com/enmwmak/ScreamDetector/blob/master/src/edu/polyu/mfcc/MFCC.java
The issue I'm having is that after a few iterations, I run into the problem that the file doesnt get created, and then get a null error passing the results from the input stream to the tensorflow model.
Possible Issues
One reason could be where the file is stored. I've been trying to send the file to local storage because I was worried that all the devices wouldnt have external storage.
Another reason could be that i'm not calling the sound recognition in the right spot. I waited will after the mediaRecorder is stopped to make sure that the file is written with the mic audio, but when I review the contents of the fileInputStream, it appears to not be working, and in each loop the file is always the same.
Any help would be much appreciated.

It may be tricky to have a sleep(2000) inside while loop.
It may be better to check millis and break until 2000 ms has lapsed.

Creation of GIF is taking so long time in Android

I am creating a app which burst capture images and create a GIF as output. My problem is creation of GIF from the image sequence is taking so long time, whether the resolution of images are 320x240. I am using AnimatedGifEncoder class for GIF encoding. as follow this link.
My code for creation of GIF is as following
private void saveGifImage() {
FileOutputStream outStream =
String fileName = "test.gif";
try {
File file = new File(Environment.getExternalStorageDirectory() + "/gif_convertor/sample/");
if (!file.exists())
file.mkdirs();
File file1 = new File(file + File.separator +
if (file1.exists()) {
} else {
try {
// file1.mkdirs();
file1.createNewFile();
} catch (Exception e) {
}
}
outStream = new FileOutputStream(file1);
Log.d("Location", file1.getPath().toString());
outStream.write(generateGIF());
outStream.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
DialogUtils.stopProgressDisplay();
}
}
private byte[] generateGIF() {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
AnimatedGifEncoder encoder = new AnimatedGifEncoder();
encoder.start(bos);
encoder.delay = 33; // 50 means 0.5 seconds ( 100 value is equivalent to 1 seconds)
encoder.repeat = 0; // 0 means repeat forever, other n positive integer means n times repeat , -1 means no repeat
encoder.sizeSet = true; // resize allowed with true flag
encoder.width = 320;
encoder.height = 240;
File tempDir = new File(getActivity().getExternalFilesDir(null), "temp");
if (tempDir.exists()) {
for (File file : tempDir.listFiles()) {
Bitmap bitmap = BitmapFactory.decodeFile(file.getAbsolutePath());
encoder.addFrame(bitmap);
}
}
encoder.finish();
return bos.toByteArray();
}

Split large file into chunks

I have a method which accept file and size of chunks and return list of chunked files. But the main problem that my line in file could be broken, for example in main file I have next lines:
|1|aaa|bbb|ccc|
|2|ggg|ddd|eee|
After split I could have in one file:
|1|aaa|bbb
In another file:
|ccc|2|
|ggg|ddd|eee|
Here is the code:
public static List<File> splitFile(File file, int sizeOfFileInMB) throws IOException {
int counter = 1;
List<File> files = new ArrayList<>();
int sizeOfChunk = 1024 * 1024 * sizeOfFileInMB;
byte[] buffer = new byte[sizeOfChunk];
try (BufferedInputStream bis = new BufferedInputStream(new FileInputStream(file))) {
String name = file.getName();
int tmp = 0;
while ((tmp = bis.read(buffer)) > 0) {
File newFile = new File(file.getParent(), name + "."
+ String.format("%03d", counter++));
try (FileOutputStream out = new FileOutputStream(newFile)) {
out.write(buffer, 0, tmp);
}
files.add(newFile);
}
}
return files;
}
Should I use RandomAccessFile class for above purposes (main file is really big - more then 5 Gb)?

If you don't mind to have chunks of different lengths (<=sizeOfChunk but closest to it) then here is the code:
public static List<File> splitFile(File file, int sizeOfFileInMB) throws IOException {
int counter = 1;
List<File> files = new ArrayList<File>();
int sizeOfChunk = 1024 * 1024 * sizeOfFileInMB;
String eof = System.lineSeparator();
try (BufferedReader br = new BufferedReader(new FileReader(file))) {
String name = file.getName();
String line = br.readLine();
while (line != null) {
File newFile = new File(file.getParent(), name + "."
+ String.format("%03d", counter++));
try (OutputStream out = new BufferedOutputStream(new FileOutputStream(newFile))) {
int fileSize = 0;
while (line != null) {
byte[] bytes = (line + eof).getBytes(Charset.defaultCharset());
if (fileSize + bytes.length > sizeOfChunk)
break;
out.write(bytes);
fileSize += bytes.length;
line = br.readLine();
}
}
files.add(newFile);
}
}
return files;
}
The only problem here is file charset which is default system charset in this example. If you want to be able to change it let me know. I'll add third parameter to "splitFile" function for it.

Just in case anyone is interested in a Kotlin version.
It creates an iterator of ByteArray chunks:
class ByteArrayReader(val input: InputStream, val chunkSize: Int, val bufferSize: Int = 1024*8): Iterator<ByteArray> {
var eof: Boolean = false
init {
if ((chunkSize % bufferSize) != 0) {
throw RuntimeException("ChunkSize(${chunkSize}) should be a multiple of bufferSize (${bufferSize})")
}
}
override fun hasNext(): Boolean = !eof
override fun next(): ByteArray {
var buffer = ByteArray(bufferSize)
var chunkWriter = ByteArrayOutputStream(chunkSize) // no need to close - implementation is empty
var bytesRead = 0
var offset = 0
while (input.read(buffer).also { bytesRead = it } > 0) {
if (chunkWriter.use { out ->
out.write(buffer, 0, bytesRead)
out.flush()
offset += bytesRead
offset == chunkSize
}) {
return chunkWriter.toByteArray()
}
}
eof = true
return chunkWriter.toByteArray()
}
}

Split a file to multiple chunks (in memory operation), here I'm splitting any file to a size of 500kb(500000 bytes) and adding to a list :
public static List<ByteArrayOutputStream> splitFile(File f) {
List<ByteArrayOutputStream> datalist = new ArrayList<>();
try {
int sizeOfFiles = 500000;
byte[] buffer = new byte[sizeOfFiles];
try (FileInputStream fis = new FileInputStream(f); BufferedInputStream bis = new BufferedInputStream(fis)) {
int bytesAmount = 0;
while ((bytesAmount = bis.read(buffer)) > 0) {
try (OutputStream out = new ByteArrayOutputStream()) {
out.write(buffer, 0, bytesAmount);
out.flush();
datalist.add((ByteArrayOutputStream) out);
}
}
}
} catch (Exception e) {
//get the error
}
return datalist;
}

Split files in chunks depending upon your chunk size
val f = FileInputStream(file)
val data = ByteArray(f.available()) // Size of original file
var subData: ByteArray
f.read(data)
var start = 0
var end = CHUNK_SIZE
val max = data.size
if (max > 0) {
while (end < max) {
subData = data.copyOfRange(start, end)
start = end
end += CHUNK_SIZE
if (end >= max) {
end = max
}
//Function to upload your chunk
uploadFileInChunk(subData, isLast = false)
}
// For the Last Chunk
end--
subData = data.copyOfRange(start, end)
uploadFileInChunk(subData, isLast = true)
}
If you are taking the file from the user through intent you may get file URI as content, so in that case.
Uri uri = data.getData();
InputStream inputStream = getContext().getContentResolver().openInputStream(uri);
fileInBytes = IOUtils.toByteArray(inputStream);
Add the dependency in you build gradle to use IOUtils
compile 'commons-io:commons-io:2.11.0'
Now do a little modification in the above code to send your file to server.
var subData: ByteArray
var start = 0
var end = CHUNK_SIZE
val max = fileInBytes.size
if (max > 0) {
while (end < max) {
subData = fileInBytes.copyOfRange(start, end)
start = end
end += CHUNK_SIZE
if (end >= max) {
end = max
}
uploadFileInChunk(subData, isLast = false)
}
// For the Last Chunk
end--
subData = fileInBytes.copyOfRange(start, end)
uploadFileInChunk(subData, isLast = true)
}