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creating Socket to connect to windows 10 machine from Raspberry pi 4 Raspbian does not work (Java)

I have a Raspberry pi 4 with Raspbian installed, and I have a computer with Windows 10 installed.I wrote two functions one send a file and the other one receive the file.
when I run this function that sends a file on the raspberry pi 4:
public static void sendFile(String fileName, String ip)
{
BufferedOutputStream outputStream = null;
PrintWriter writer = null;
BufferedReader reader = null;
FileInputStream filein = null;
File file = new File(fileName);
if (!file.exists())
{
System.out.println(fileName + " does not exist");
return;
}
try
{
Socket socket = new Socket(ip, port);
outputStream = new BufferedOutputStream(socket.getOutputStream());
writer = new PrintWriter(socket.getOutputStream());
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
filein = new FileInputStream(file);
long fileSize = file.length();
writer.println(fileName); // sending file name
writer.println(fileSize); // sending file size in bytes
writer.flush();
byte[] dataBuffer = new byte[1024];
int numberOfReadBytes = 0; // the number of read bytes for each read() function call
System.out.println("Entering the loop");
for(long i = 0; i < fileSize && numberOfReadBytes > -1;)
{
numberOfReadBytes = filein.read(dataBuffer); // read read() function returns the number of bytes tha has been assigned to the array or -1 if EOF(end of file) is reached
outputStream.write(dataBuffer, 0, numberOfReadBytes); // writing the bytes in dataBuffer from index 0 to index numberOfBytes
i += numberOfReadBytes;
}
outputStream.flush();
System.out.println(fileName + " sent to " + ip);
String status = reader.readLine();
System.out.println("Status: " + status + "\t file save successfully on the other machine.");
}
catch(IOException ioe)
{
System.err.println("Status: 0\n" + ioe.getMessage());
}
finally // closing streams
{
try
{
outputStream.close();
reader.close();
writer.close();
filein.close();
}
catch (IOException ioe)
{
System.err.println("Error closing the connection.");
}
}
}
it stops at this line Socket socket = new Socket(ip, port);
and this is the other function that runs on windows 10
public static void receiveFile()
{
// 1- read the file name
// 2- read the size of the file
// 3- read the file and write it
ServerSocket server = null;
Socket socket = null;
BufferedReader reader = null;
BufferedInputStream inputStream = null;
FileOutputStream fileout = null;
PrintWriter writer = null;
try
{
server = new ServerSocket(9999);
socket = server.accept();
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
inputStream = new BufferedInputStream(socket.getInputStream());
writer = new PrintWriter(socket.getOutputStream());
String fileName = reader.readLine(); // reading file name
long fileSize = Long.parseLong(reader.readLine()); // reading file size
System.out.println(fileSize);
// reading file data and write the data
File file = new File(fileName);
fileout = new FileOutputStream(file);
for (long i = 0; i < fileSize; ++i)
{
fileout.write(inputStream.read());
System.out.println(i);
}
fileout.flush();
fileout.close();
writer.println('1');
System.out.println("Status: 1");
System.out.println(fileName+ " is saved successfully");
}
catch (IOException ioe)
{
System.err.println("Status: 0");
System.err.println(ioe.getMessage());
}
finally
{
try
{
reader.close();
inputStream.close();
}
catch(IOException ioe)
{
System.err.println("Error closing connection\n" + ioe.getMessage());
}
}
}
I think windows 10 firewall blocks connection, but I am not sure.

It turns out it was the firewall blocking connection from the raspberry pi

java: send large files through sockets

So im making a client-server based architecture programm where server is sending a file and client receives it.
I have seen a lot of code parts and i also made a lot where i send small files. ex images. In my case i want to send .wav audio files which are large(40mb). This is what i have done so far. When i run my client, it just proceed to download, but never really downloads the file. I guess its because its too large.
How to send such large files?
server
public void send_file_to_client(String requested_file) throws IOException {
FileInputStream fis = null;
BufferedInputStream bis = null;
File FILE_TO_SEND = new File("C:\\ServerMusicStorage\\" + requested_file + ".wav");
byte[] mybytearray = new byte[(int) FILE_TO_SEND.length()];
try {
fis = new FileInputStream(FILE_TO_SEND);
bis = new BufferedInputStream(fis);
} catch (FileNotFoundException ex) {
Logger.getLogger(ClientHandler.class.getName()).log(Level.SEVERE, null, ex);
}
OutputStream os = null;
bis.read(mybytearray, 0, mybytearray.length);
os = connsock.getOutputStream();
System.out.println("Sending " + FILE_TO_SEND + "(" + mybytearray.length + " bytes)");
toClient.writeUTF(Integer.toString(mybytearray.length));
os.write(mybytearray, 0, mybytearray.length);
os.flush();
System.out.println("Done.");
if (bis != null) {
bis.close();
}
if (os != null) {
os.close();
}
if (connsock != null) {
connsock.close();
}
}
client
public static void receive_file(String requested_file) throws IOException {
File file_to_save = new File("C:\\ClientMusicStorage\\" + requested_file + ".wav");
int bytesRead;
int current = 0;
FileOutputStream fos = null;
BufferedOutputStream bos = null;
//get file size to create the bytearray
String fileSize=fromServer.readUTF();
int final_file_size = Integer.parseInt(fileSize);
byte[] mybytearray = new byte[final_file_size];
InputStream is = clientSocket.getInputStream();
fos = new FileOutputStream(file_to_save);
bos = new BufferedOutputStream(fos);
bytesRead = is.read(mybytearray, 0, mybytearray.length);
current = bytesRead;
do {
bytesRead
= is.read(mybytearray, current, (mybytearray.length - current));
if (bytesRead >= 0) {
current += bytesRead;
}
} while (bytesRead > -1);
bos.write(mybytearray, 0, current);
bos.flush();
}

Send file via socket - buffer size [duplicate]

This question already has answers here:
Java multiple file transfer over socket
(3 answers)
Closed 5 years ago.
TL;DR: How do I send (with a single connection) file, its size and its name. All examples in the internet send a file alone.
Server:
public class Server {
private static int PORT = 6667;
private ServerSocket serverSocket;
public void run() throws IOException {
System.out.println("Opening server");
serverSocket = new ServerSocket(PORT);
while(true) {
try(Socket incomingSocket = serverSocket.accept()) {
System.out.println("Accepted connection: " + incomingSocket);
incomingSocket.setSoTimeout(2000); // Don't let scanner block the thread.
InputStream inputStream = incomingSocket.getInputStream();
Scanner scanner = new Scanner(inputStream);
String command = "";
if(scanner.hasNextLine())
command = scanner.nextLine();
if(command.equals("update")) {
File file = new File("abc.txt");
sendFile(incomingSocket, file);
}
else {
// ...
System.out.println("Another command");
}
}
}
}
private void sendFile(Socket socket, File file) throws IOException {
byte[] bytes = new byte[(int)file.length()];
FileInputStream fileInputStream = new FileInputStream(file);
BufferedInputStream bufferedInputStream = new BufferedInputStream(fileInputStream);
bufferedInputStream.read(bytes, 0, bytes.length);
OutputStream outputStream = socket.getOutputStream();
PrintWriter writer = new PrintWriter(outputStream, true);
writer.println(file.length());
writer.println(file.getName());
System.out.println("Sending " + file.getName() + "(" + bytes.length + " bytes) to " + socket);
outputStream.write(bytes, 0, bytes.length);
outputStream.flush();
System.out.println("File sent");
}
public void stopRunning() {
try {
serverSocket.close();
} catch(IOException e) {
e.printStackTrace();
}
}
}
Client:
public class Client {
private static String HOST = "localhost";
private static int PORT = 6667;
public void run() throws IOException {
Socket socket = new Socket(HOST, PORT);
System.out.println("Connecting...");
OutputStream outputStream = socket.getOutputStream();
PrintWriter writer = new PrintWriter(outputStream, true);
writer.println("update"); // Example command which will determine what server sends back
receiveFile(socket);
socket.close();
}
private void receiveFile(Socket socket) throws IOException {
InputStream inputStream = socket.getInputStream();
int size = 16384;
String name = "example.txt";
Scanner scanner = new Scanner(inputStream);
size = Integer.parseInt(scanner.next());
name = scanner.next();
FileOutputStream fileOutputStream = new FileOutputStream(name);
BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(fileOutputStream);
byte[] buffer = new byte[size];
int bytesRead, totalRead = 0;
while ((bytesRead = inputStream.read(buffer, 0, buffer.length)) != -1) {
totalRead += bytesRead;
bufferedOutputStream.write(buffer, 0, bytesRead);
}
bufferedOutputStream.flush();
System.out.println("File " + name + " received. " + totalRead + " bytes read");
bufferedOutputStream.close();
fileOutputStream.close();
}
I want my server to send a file to the client. It should also include the file's name and its size. Name because it's quite important and the size because I don't want to make a hardcoded buffer with a huge size.
Tried it with the code above. The client's "scanner part"
Scanner scanner = new Scanner(inputStream);
size = Integer.parseInt(scanner.next());
name = scanner.next();
works just okay, but the file is not received. inputStream.read(buffer, 0, buffer.length) never reads the remaining bytes from the stream.
If i comment out the scanner part, the bytes are read correctly(size and name information + file itself)
So, the question is, how do I send it with a single connection? Or should I make 2 separate connections, in the first one asking for size and file name and sending the file in the second one?

Scanner is good for text-based work.
One way to do what you want is using DataInputStream and DataOutputStream. Only one connection is needed:
public void send(File file, OutputStream os) throws IOException {
DataOutputStream dos = new DataOutputStream(os);
// writing name
dos.writeUTF(file.getName());
// writing length
dos.writeLong(file.length());
// writing file content
... your write loop, write to dos
dos.flush();
}
public void receive(InputStream is) throws IOException {
DataInputStream dis = new DataInputStream(is);
String fileName = dis.readUTF();
long fileSize = dis.readLong();
// reading file content
... your read loop, read from dis
}

Transferring Files via TCP/IP works in Windows but not Ubuntu

I was trying my hands at sending multiple files using TCP/IP connection with the help of this guide.
When I execute my testClient codes from Ubuntu 14.04, files are transferred over to testServer in Windows 7. The .txt files received here are in correct format.
However, when I execute testClients codes from Windows 7 and testServer from Ubuntu 14.04, the files received in Ubuntu 14.04 was messed up. (The contents from txt#2 contents spill over to txt#1.)
During the swap, none of the codes in both testServer and testClients were changed other than their IP address and file location.
I am confused. Why did the codes work fine in Windows 7 but not in Ubuntu? Is there something wrong with my codes? I would appreciate any help on this.
TestServer.java
public static void main(String[] args) throws IOException {
FileOutputStream fos;
BufferedOutputStream bos;
OutputStream output;
DataOutputStream dos;
int len;
int smblen;
InputStream in;
boolean flag = true;
DataInputStream clientData;
BufferedInputStream clientBuff;
ServerSocket serverSocket = new ServerSocket(5991);
serverSocket.setSoTimeout(500000);
System.out.println("Waiting for client on port " + serverSocket.getLocalPort());
Socket clientSocket = null;
clientSocket = serverSocket.accept();
System.out.println("Just connected to " + clientSocket.getRemoteSocketAddress());
while (true){
while(flag==true) {
in = clientSocket.getInputStream();
clientData = new DataInputStream(in);
clientBuff = new BufferedInputStream(in);
int fileSize = clientData.read();
if (fileSize != 0)
System.out.println("Receiving " + fileSize + " files.\n");
//Store filenames and file sizes from client directory
ArrayList<File>files=new ArrayList<File>(fileSize);
ArrayList<Integer>sizes = new ArrayList<Integer>(fileSize);
//Server accepts filenames
for (int count=0; count<fileSize; count ++){
File ff=new File(clientData.readUTF());
files.add(ff);
}
for (int count=0; count<fileSize; count ++){
sizes.add(clientData.readInt());
}
for (int count=0; count<fileSize; count++) {
if (fileSize - count == 1) {
flag = false;
}
len = sizes.get(count);
output = new FileOutputStream("/home/pp/Desktop/inResources/" + files.get(count));
dos = new DataOutputStream(output);
bos = new BufferedOutputStream(output);
byte[] buffer = new byte[1024];
bos.write(buffer, 0, buffer.length);
while (len > 0 && (smblen = clientData.read(buffer)) > 0) {
dos.write(buffer, 0, smblen);
len = len - smblen;
dos.flush();
}
dos.close();
System.out.println("File " + files.get(count) + " with " + sizes.get(count) + " bytes recieved.");
}
}
if (flag == false) {
System.out.println("\nTransfer completed. Closing socket...");
serverSocket.close();
break;
}
}
}
TestClient.java
public static void main(String[] args) throws IOException {
String serverName = "192.168.1.12"; //IP address
int port = 5991;
Socket sock = new Socket(serverName, port);
System.out.println("Connected to " + serverName + " on port " + port + "\n");
File myFile = new File("C:\\Users\\inter2\\Desktop\\noobs\\outResources");
File[] files = myFile.listFiles();
OutputStream os = sock.getOutputStream();
DataOutputStream dos = new DataOutputStream(os);
//Sending total number of files in folder
dos.writeInt(files.length);
//Sending file names
for (int count=0; count<files.length; count++) {
dos.writeUTF(files[count].getName());
}
//Sending file sizes
for (int count=0; count<files.length; count++) {
int filesize = (int) files[count].length();
dos.writeInt(filesize);
}
//Sending of files
for (int count=0; count<files.length; count ++) {
int filesize = (int) files[count].length();
byte [] buffer = new byte [filesize];
FileInputStream fis = new FileInputStream(files[count].toString());
BufferedInputStream bis = new BufferedInputStream(fis);
//Sending file name and file size to the server
bis.read(buffer, 0, buffer.length);
dos.write(buffer, 0, buffer.length);
dos.flush();
System.out.println("Sending file " + files[count].getName() + " with " + filesize + " bytes.");
}
System.out.println("\n" + files.length + " files successfully transfered.");
sock.close();
}

This code never worked.
int fileSize = clientData.read();
Here you are reading the amount of files, as a byte.
dos.writeInt(files.length)
Here you are writing that amount, as an int. So already your writer is three bytes ahead of your reader.
Change read() to readInt() above.
Other notes:
Receiving:
byte[] buffer = new byte[1024];
This is OK but a bigger buffer would be more efficient, say 8192.
bos.write(buffer, 0, buffer.length);
This is a bug. Remove it. You are writing 1024 null bytes at the beginning of the file.
while (len > 0 && (smblen = clientData.read(buffer)) > 0) {
dos.write(buffer, 0, smblen);
len = len - smblen;
dos.flush();
Don't flush inside loops.
}
Sending:
byte [] buffer = new byte [filesize];
FileInputStream fis = new FileInputStream(files[count].toString());
BufferedInputStream bis = new BufferedInputStream(fis);
//Sending file name and file size to the server
bis.read(buffer, 0, buffer.length);
dos.write(buffer, 0, buffer.length);
No need to waste a buffer of the size of the file. Use the same code you use for receiving above.

Java Socket Programming Buffer for Large File

I am trying to transfer a large file from a server to a client. My code so far works but only if I set the buffer size in the client code to the exact size of the file. I won't always know what the file size is going to be. I keep finding examples that claim it doesn't matter what the size of the file or buffer is because it will just keep reading from the input stream...? However, when I implement the code that supposedly does this, it transfers 0 bytes.
Client:
public static void main (String [] args ) throws IOException {
int bytesRead;
int current = 0;
FileOutputStream fos = null;
BufferedOutputStream bos = null;
Socket sock = null;
try {
sock = new Socket(hostname, 20000);
System.out.println("Connecting...");
// receive file
InputStream is = sock.getInputStream();
fos = new FileOutputStream(FILE_TO_RECEIVE);
bos = new BufferedOutputStream(fos);
//////////// replaced this ////////////////////////////
byte[] buffer = new byte[BUFFER_SIZE];
bytesRead = is.read(buffer,0,buffer.length);
current = bytesRead;
do {
bytesRead = is.read(buffer, current, (buffer.length-current));
if(bytesRead >= 0){ current += bytesRead;}
} while(bytesRead > 0);
bos.write(buffer, 0 , current);
///////////////////////////////////////
// with this:
// int count;
// byte[] buffer = new byte[8192];
// while ((count = is.read(buffer)) > 0)
// {
// bos.write(buffer, 0, count);
// }
//////////// transfers 0 bytes ///////////
bos.flush();
System.out.println("File " + FILE_TO_RECEIVE
+ " downloaded (" + current + " bytes read)");
}
finally {
if (fos != null){ fos.close();}
if (bos != null){ bos.close();}
if (sock != null){ sock.close();}
}
}
Server:
public static void main(String[] args) throws IOException{
FileInputStream fis = null;
BufferedInputStream bis = null;
OutputStream os = null;
ServerSocket servsock = null;
Socket sock = null;
try {
servsock = new ServerSocket(20000);
while (true) {
System.out.println("Waiting...");
try {
sock = servsock.accept();
System.out.println("Accepted connection : " + sock);
// send file
File myFile = new File (FILE_TO_SEND);
byte [] mybytearray = new byte [(int)myFile.length()];
fis = new FileInputStream(myFile);
bis = new BufferedInputStream(fis);
bis.read(mybytearray,0,mybytearray.length);
os = sock.getOutputStream();
System.out.println("Sending " + FILE_TO_SEND + "(" + mybytearray.length + " bytes)");
os.write(mybytearray,0,mybytearray.length);
os.flush();
System.out.println("Done.");
}
finally {
if (bis != null){ bis.close();}
if (os != null){ os.close();}
if (sock!=null){ sock.close();}
}
}
}
finally {
if (servsock != null){
servsock.close();
}
}
}
Thank you for your help

Your copy loops are both different, and both nonsense. One of them isn't even a loop. Try this:
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
This works for any buffer of size >= one byte.
Use this at both ends.