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How to read InputStream twice if I am using ReadableByteChannel and BufferedReader?

How to read an InputStream twice if I am using ReadableByteChannel and BufferedReader?
Here is my code:
ReadableByteChannel inputChannel = Channels.newChannel(input);
WritableByteChannel outputChannel = Channels.newChannel(output);
InputStream ind = Channels.newInputStream(inputChannel);
ReadableByteChannel inputChannel1 = Channels.newChannel(ind);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
org.apache.commons.io.IOUtils.copy(ind, baos);
ByteBuffer buffer = ByteBuffer.allocateDirect(10240);
long size = 0;
while (inputChannel1.read(buffer) != -1) {
buffer.flip();
size += outputChannel.write(buffer);
buffer.clear();
}
byte[] bytes = baos.toByteArray();
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
BufferedReader in = new BufferedReader(new InputStreamReader(bais));
String inputLine;
StringBuffer bufferResponse = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
bufferResponse.append(inputLine);
}
JSONObject jsonResponse = new JSONObject(bufferResponse.toString());

You've written a lot of code to copy input to two destinations: output and jsonResponse. As you have made an in-memory copy of input => bytes there is no need to scan input twice, and you don't need to use IOUtils for a simple copy to byte[] which you can re-use to send to the two destinations:
ByteArrayOutputStream baos = new ByteArrayOutputStream();
input.transferTo(baos);
byte[] bytes = baos.toByteArray();
output.write(bytes);
Then do as #g00se suggests - if the char encoding is platform default:
String s = new String(bytes /*, or insert another charset here */);
JSONObject jsonResponse = new JSONObject(s);
You should also deal with closing the input/output streams, best done with try-with-resources block.

send images through java android sockets

I want to send images through sockets but I have not been able to do it in android, could someone help me?
System.out.println("iniciooooo");
//converting image to bytes with base64
Bitmap b = BitmapFactory.decodeFile("/sdcard/ajeffer.jpg");
ByteArrayOutputStream byte2= new ByteArrayOutputStream();
b.compress(Bitmap.CompressFormat.JPEG,70,byte2);
byte[] enbytes = byte2.toByteArray();
String bb = Base64.encodeToString(enbytes,Base64.DEFAULT);
System.out.println(Base64.encodeToString(enbytes,Base64.DEFAULT));
data.writeUTF(bb);
FileOutputStream file;
//receiving the image in bytes to convert it into an image
DataInputStream dain = new DataInputStream(s.getInputStream());
msg = dain.readUTF();
File ff = new File("/sdcard/a2jeffer.jpg");
byte[] deco = Base64.decode(dain.readUTF(),Base64.DEFAULT);
Bitmap bit = BitmapFactory.decodeByteArray(deco,0,deco.length);
file = new FileOutputStream(ff);
bit.compress(Bitmap.CompressFormat.JPEG,70,file);
//the image is not created

I realized that my code did not work because I had to put this android: requestLegacyExternalStorage =" true " in the manifest, also I see that you are right about writeUTF () since in order to send images I must drastically lower the quality but it works If you have an idea on how to improve this, let me know, thank you very much.

You were right, this works great for sending and receiving any file.
Send file
OutputStream outputStream = socket.getOutputStream();
InputStream inputStream = new FileInputStream(file);
byte[] datita = new byte[16*1024];
int count;
while((count = inputStream.read(datita))>0){
outputStream.write(datita,0,count);
}
outputStream.close();
inputStream.close();
Receive file
OutputStream outputStream = new FileOutputStream(file);
InputStream inputStream = s.getInputStream();
byte[] datita = new byte[16*1024];
int count;
while((count = inputStream.read(datita))>0){
outputStream.write(datita,0,count);
}
outputStream.close();
inputStream.close();

java.io.StreamCorruptedException: invalid stream header when sending an image

In my server i'm trying to split an image and send it to the clients (here are called resources). The problem is that I get StreamCorruptedException when I read the object.
Server side:
Socket resSocket = resourceQueue.get(k).getSocket();
DataOutputStream dos = new DataOutputStream(resSocket.getOutputStream());
FileInputStream fis = new FileInputStream(chunksList.get(i));
byte[] data = new byte[fis.available()];
fis.read(data);
ObjectOutputStream oos = new ObjectOutputStream(resSocket.getOutputStream());
oos.writeObject(data);
oos.close();
Client side
ObjectInputStream ois = new ObjectInputStream(sock.getInputStream()); // Here i get the error
byte[] buffer = (byte[]) ois.readObject();
String path = "c:/JGCF/temp."+"jpg";
System.out.println(path);
FileOutputStream fos = new FileOutputStream(path);
fos.write(buffer);

How do you read from an InputStream in Java and convert to byte array?

I am currently trying to read in data from a server response. I am using a Socket to connect to a server, creating a http GET request, then am using a Buffered Reader to read in data. Here is what the code looks like compacted:
Socket conn = new Socket(server, 80);
//Request made here
BufferedReader inFromServer = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String response;
while((response = inFromServer.readLine()) != null){
System.out.println(response);
}
I would like to read in the data, instead of as a String, as a byte array, and write it to a file. How is this possible? Any help is greatly appreciated, thank you.

You need to use a ByteArrayOutputStream, do something like the below code:
Socket conn = new Socket(server, 80);
//Request made here
InputStream is = conn.getInputStream();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int readBytes = -1;
while((readBytes = is.read(buffer)) > 1){
baos.write(buffer,0,readBytes);
}
byte[] responseArray = baos.toByteArray();

One way is to use Apache commons-io IOUtils
byte[] bytes = IOUtils.toByteArray(inputstream);

With plain java:
ByteArrayOutputStream output = new ByteArrayOutputStream();
try(InputStream stream = new FileInputStream("myFile")) {
byte[] buffer = new byte[2048];
int numRead;
while((numRead = stream.read(buffer)) != -1) {
output.write(buffer, 0, numRead);
}
} catch(IOException e) {
e.printStackTrace();
}
// and here your bytes
byte[] myDesiredBytes = output.toByteArray();

If you are not using Apache commons-io library in your project,I have pretty simple method to do the same without using it..
/*
* Read bytes from inputStream and writes to OutputStream,
* later converts OutputStream to byte array in Java.
*/
public static byte[] toByteArrayUsingJava(InputStream is)
throws IOException{
ByteArrayOutputStream baos = new ByteArrayOutputStream();
int reads = is.read();
while(reads != -1){
baos.write(reads);
reads = is.read();
}
return baos.toByteArray();
}

How to convert byte array to long without using java.nio?

I am implementing a reliable data transfer protocol. I need to pass the checksum which is long value to a receiver. I am not allowed to use java.nio.
I know how to convert long to byte array as show below:
ByteArrayOutputStream baos = new ByteArrayOutputStream();
DataOutputStream dos = new DataOutputStream(baos);
dos.writeLong(someLong);
dos.close();
byte[] longBytes = baos.toByteArray();
But how do I convert byte array to long without using java.nio?

You can do like this
ByteArrayInputStream bais = new ByteArrayInputStream(longBytes);
DataInputStream dis = new DataInputStream(bais);
someLong = dis.readLong();