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How to create File from list of byte arrays in Android?

I am trying to transfer a .mp4 file using WebRTC and it's DataChannel. In order to do that I am breaking the file into chunks like below:
FileInputStream is = new FileInputStream(file);
byte[] chunk = new byte[260000];
int chunkLen = 0;
sentFileByte = new ArrayList<>();
while ((chunkLen = is.read(chunk)) != -1) {
sentFileByte.add(chunk);
}
After that, sending the chunks by index like:
byte[] b = sentFileByte.get(index);
ByteBuffer bb = ByteBuffer.wrap(b);
bb.put(b);
bb.flip();
dataChannel.send(new DataChannel.Buffer(bb, true));
On the receiver end I am receiving the chunks and adding it to an Arraylist
receivedFileByteArr.add(chunkByteArr);
After receiving all the chunks successfully I am trying to convert these in to a file like below:
String path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).getAbsolutePath() + "/" + fileName;
File file = new File(path);
try {
FileOutputStream fileOutputStream = new FileOutputStream(file);
for (int i = 0; i < receivedFileByteArr.size(); i++) {
fileOutputStream.write(receivedFileByteArr.get(i));
}
fileOutputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
After completing all these steps, file is created successfully. File size is also same. But problem is the file is not playable in any video player. I guess I am making some mistake on FileInputStream and FileOutputStream. I need help to fix this error.

A java program that creates WAV files [duplicate]

With Java:
I have a byte[] that represents a file.
How do I write this to a file (ie. C:\myfile.pdf)
I know it's done with InputStream, but I can't seem to work it out.

Use Apache Commons IO
FileUtils.writeByteArrayToFile(new File("pathname"), myByteArray)
Or, if you insist on making work for yourself...
try (FileOutputStream fos = new FileOutputStream("pathname")) {
fos.write(myByteArray);
//fos.close(); There is no more need for this line since you had created the instance of "fos" inside the try. And this will automatically close the OutputStream
}

Without any libraries:
try (FileOutputStream stream = new FileOutputStream(path)) {
stream.write(bytes);
}
With Google Guava:
Files.write(bytes, new File(path));
With Apache Commons:
FileUtils.writeByteArrayToFile(new File(path), bytes);
All of these strategies require that you catch an IOException at some point too.

Another solution using java.nio.file:
byte[] bytes = ...;
Path path = Paths.get("C:\\myfile.pdf");
Files.write(path, bytes);

Also since Java 7, one line with java.nio.file.Files:
Files.write(new File(filePath).toPath(), data);
Where data is your byte[] and filePath is a String. You can also add multiple file open options with the StandardOpenOptions class. Add throws or surround with try/catch.

From Java 7 onward you can use the try-with-resources statement to avoid leaking resources and make your code easier to read. More on that here.
To write your byteArray to a file you would do:
try (FileOutputStream fos = new FileOutputStream("fullPathToFile")) {
fos.write(byteArray);
} catch (IOException ioe) {
ioe.printStackTrace();
}

Try an OutputStream or more specifically FileOutputStream

Basic example:
String fileName = "file.test";
BufferedOutputStream bs = null;
try {
FileOutputStream fs = new FileOutputStream(new File(fileName));
bs = new BufferedOutputStream(fs);
bs.write(byte_array);
bs.close();
bs = null;
} catch (Exception e) {
e.printStackTrace()
}
if (bs != null) try { bs.close(); } catch (Exception e) {}

File f = new File(fileName);
byte[] fileContent = msg.getByteSequenceContent();
Path path = Paths.get(f.getAbsolutePath());
try {
Files.write(path, fileContent);
} catch (IOException ex) {
Logger.getLogger(Agent2.class.getName()).log(Level.SEVERE, null, ex);
}

////////////////////////// 1] File to Byte [] ///////////////////
Path path = Paths.get(p);
byte[] data = null;
try {
data = Files.readAllBytes(path);
} catch (IOException ex) {
Logger.getLogger(Agent1.class.getName()).log(Level.SEVERE, null, ex);
}
/////////////////////// 2] Byte [] to File ///////////////////////////
File f = new File(fileName);
byte[] fileContent = msg.getByteSequenceContent();
Path path = Paths.get(f.getAbsolutePath());
try {
Files.write(path, fileContent);
} catch (IOException ex) {
Logger.getLogger(Agent2.class.getName()).log(Level.SEVERE, null, ex);
}

I know it's done with InputStream
Actually, you'd be writing to a file output...

This is a program where we are reading and printing array of bytes offset and length using String Builder and Writing the array of bytes offset length to the new file.
`Enter code here
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
//*This is a program where we are reading and printing array of bytes offset and length using StringBuilder and Writing the array of bytes offset length to the new file*//
public class ReadandWriteAByte {
public void readandWriteBytesToFile(){
File file = new File("count.char"); //(abcdefghijk)
File bfile = new File("bytefile.txt");//(New File)
byte[] b;
FileInputStream fis = null;
FileOutputStream fos = null;
try{
fis = new FileInputStream (file);
fos = new FileOutputStream (bfile);
b = new byte [1024];
int i;
StringBuilder sb = new StringBuilder();
while ((i = fis.read(b))!=-1){
sb.append(new String(b,5,5));
fos.write(b, 2, 5);
}
System.out.println(sb.toString());
}catch (IOException e) {
e.printStackTrace();
}finally {
try {
if(fis != null);
fis.close(); //This helps to close the stream
}catch (IOException e){
e.printStackTrace();
}
}
}
public static void main (String args[]){
ReadandWriteAByte rb = new ReadandWriteAByte();
rb.readandWriteBytesToFile();
}
}
O/P in console : fghij
O/P in new file :cdefg

You can try Cactoos:
new LengthOf(new TeeInput(array, new File("a.txt"))).value();
More details: http://www.yegor256.com/2017/06/22/object-oriented-input-output-in-cactoos.html

Android Base64 Audio File Encode / Decode

Doing: I am currently recording voice and saving it as a file in sdCard which is running playing fine in MediaPlayer.
What i want: When i encode this file intoBase64 and send to server, everything goes fine. But When i decode the Base64 String into audio.m4a file, it is not running in MediaPlayer.
I had tried .m4a , .wav but all in vain.
The problem is in encoding. Because when i decode a file sent from the same iOS app, it runs fine in MediaPlayer.
I know its very basic and alot of help is there to encode decode but nothing is working. Following is my approach:
private void encodeAudio(String selectedPath) {
byte[] audioBytes;
try {
// Just to check file size.. Its is correct i-e; Not Zero
File audioFile = new File(selectedPath);
long fileSize = audioFile.length();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
FileInputStream fis = new FileInputStream(new File(selectedPath));
byte[] buf = new byte[1024];
int n;
while (-1 != (n = fis.read(buf)))
baos.write(buf, 0, n);
audioBytes = baos.toByteArray();
// Here goes the Base64 string
_audioBase64 = Base64.encodeToString(audioBytes, Base64.DEFAULT);
} catch (Exception e) {
DiagnosticHelper.writeException(e);
}
}
And Decoding in the following way:
private void decodeAudio(String base64AudioData, File fileName, String path, MediaPlayer mp) {
try {
FileOutputStream fos = new FileOutputStream(fileName);
fos.write(Base64.decode(base64AudioData.getBytes(), Base64.DEFAULT));
fos.close();
try {
mp = new MediaPlayer();
mp.setDataSource(path);
mp.prepare();
mp.start();
} catch (Exception e) {
DiagnosticHelper.writeException(e);
}
} catch (Exception e) {
e.printStackTrace();
}
}
Please point if i am doing anything wrong.
Thanks

The problem is before relasing audio i was converting audio into Base64 String thats why Decoded file is corrupt !! Cheers

Appending Two Mp3 files in Android

How can i append two audio files in android. I tried this but it does not work. pls give me a soln.I need to concatenate the files from sdcard that ts A.mp3 and B.mp3 .When i merge concatenate method calls i want both of them as a single file in sdcard that is C.mp3........
File original= new File("/mnt/sdcard/A.mp3");
File temp=new File("/mnt/sdcard/B.mp3");
Log.i("...............",""+path);
try {
File outFile= new File("/mnt/sdcard/C.mp3 ");
DataOutputStream out=new DataOutputStream(new BufferedOutputStream(new FileOutputStream(outFile)));
// FileOutputStream out=new FileOutputStream(outFile);
//OutputStream out = new FileOutputStream(original,true);
int m,n;
m=(int) temp.length();
n=(int) original.length();
byte[] buf1 = new byte[m];
byte[] buf2 = new byte[n];
byte[] outBytes = new byte[m+n];
DataInputStream dis1=new DataInputStream( new BufferedInputStream(new FileInputStream(original)));
DataInputStream dis2=new DataInputStream( new BufferedInputStream(new FileInputStream(temp)));
dis1.read(buf1, 0, m);
dis1.close();
dis2.readFully(buf2, 0, n);
dis2.close();
out.write(buf1);
out.write(buf2);
out.flush();
//in.close();
out.close();
System.out.println("File copied.");
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
I need to combine The File A.mp3,B.mp3 to C.mp3....

In addition to the answer of knowbody, you can refer to the mp3 file format specification for more information HERE and HERE.
There are a lot of things you should consider when stitching two mp3 files. The least to say is that they need to be encoded by the same program, with the same settings or if we're speaking about voice, to be taken from the same microphone, set with the same settings etc.

import java.io.*;
public class TwoFiles
{
public static void Main(String args[]) throws IOException
{
FileInputStream fistream1 = new FileInputStream("C:\\Temp\\1.mp3");
FileInputStream fistream2 = new FileInputStream("C:\\Temp\\2.mp3");
SequenceInputStream sistream = new SequenceInputStream(fistream1, fistream2);
FileOutputStream fostream = new FileOutputStream("C:\\Temp\\final.mp3");
int temp;
while( ( temp = sistream.read() ) != -1)
{
fostream.write(temp);
}
fostream.close();
sistream.close();
fistream1.close();
fistream2.close();
}
}
I hope is clear

Uploading binary files using dropbox java api

Could you point me out to a code or url where I can find some examples how to use dropbox java api and upload binary files like, .doc files jpg and video files.
Current examples in the web only point to uploading a text file. But when I try to read files using java InputStream and convert them to byte array and pass into dropbox file upload functions files get corrupted. Same issue with downloading files as well. Thanks in Advance.
Regards,
Waruna.
EDIT--
Code Sample
FileInputStream fis = new FileInputStream(file);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
byte [] buf = new byte[1024];
for(int readNum; (readNum = fis.read(buf)) != -1;) {
bos.write(buf, 0, readNum);
System.out.println("read "+ readNum + "bytes,");
}
ByteArrayInputStream inputStream2 = new ByteArrayInputStream(bos.toByteArray());
Entry newEntry = mDBApi.putFile("/uploads/"+file.getName(), inputStream2, file.toString().length(), null, null);
System.out.println("Done. \nRevision of file: " + newEntry.rev + " " + newEntry.mimeType);
return newEntry.rev;

The 3rd argument of DropboxAPI.putFile() should be the number of bytes to read from the input stream - You are passing the length of the filename.
Instead of
Entry newEntry = mDBApi.putFile("/uploads/"+file.getName(), inputStream2,
file.toString().length(), null, null);
Use
Entry newEntry = mDBApi.putFile("/uploads/"+file.getName(), inputStream2,
bos.size(), null, null);

I don't think you need to convert to byte array, simply use FileInputStream is enough for a file, txt as well as binary. The following code works, I just tested with JPG.
DropboxAPI<?> client = new DropboxAPI<WebAuthSession>(session);
FileInputStream inputStream = null;
try {
File file = new File("some_pic.jpg");
inputStream = new FileInputStream(file);
DropboxAPI.Entry newEntry = client.putFile("/testing.jpg", inputStream,
file.length(), null, null);
System.out.println("The uploaded file's rev is: " + newEntry.rev);
} catch (DropboxUnlinkedException e) {
// User has unlinked, ask them to link again here.
System.out.println("User has unlinked.");
} catch (DropboxException e) {
System.out.println("Something went wrong while uploading.");
} catch (FileNotFoundException e) {
System.out.println("File not found.");
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {}
}
}