I am trying to transfer a file from server to client using Java and TCP, however on the client-side I am getting a socket closed exception, whereas the server has no errors when attempting to transfer the file. I am confused about this error because I did not close the socket before trying to read from it. The server accepts the connection and sends the file, but the client gets that error. Any suggestion?
The error is:
java.net.SocketException: Socket closed
Server thread's run function:
public void run() {
System.out.println("Service thread running for client at " + socket.getInetAddress() + " on port " + socket.getPort());
try {
File file = new File("hank.txt");
FileInputStream fis = new FileInputStream(file);
BufferedInputStream bis = new BufferedInputStream(fis);
OutputStream os = socket.getOutputStream();
byte[] contents;
long fileLength = file.length();
long current = 0;
long start = System.nanoTime();
while(current!=fileLength) {
int size = 1000;
if(fileLength - current >= size) {
current += size;
}
else {
size = (int)(fileLength - current);
current = fileLength;
}
contents = new byte[size];
bis.read(contents,0,size);
os.write(contents);
System.out.println("sending file..." + (current*100)/fileLength+"% complete!");
}
os.flush();
this.socket.close();
}catch(Exception e) {
e.printStackTrace();
}
}
Client receiving the file code:
System.out.println("Going to get the file...");
socket = new Socket(response.getIP().substring(1), response.getPort());
byte[] contents = new byte[10000];
FileOutputStream fos = new FileOutputStream("hank.txt");
BufferedOutputStream bos = new BufferedOutputStream(fos);
InputStream in = socket.getInputStream();
int bytesRead = 0;
System.out.println("Starting to read file...");
while((bytesRead = is.read(contents))!=-1) { //the error points to this lin
bos.write(contents,0,bytesRead);
}
bos.flush();
bos.close();
in.close();
//
socket.close();
Input stream for this socket is available in variable in
InputStream in = socket.getInputStream();
So
Change is.read(contents)) to in.read(contents))
Can anybody help me with this here. I am a newbie and I am working on a network application where I have to create a socket connection to the IP address and port that they already given me and then send XML message to the socket and finally include the ReadMe.txt file where I will save what I have received from the server. Here's my code
private static Socket socket;
public static void main(String args[])
{
try
{
socket = new Socket( "196.37.22.179", 9011);
//Send the message to the server
//PrintStream outstrm = null;
OutputStream os = socket.getOutputStream();
OutputStreamWriter osw = new OutputStreamWriter(os);
BufferedWriter bw = new BufferedWriter(osw);
String str;
str = "<request>";
str += "<EventType>Authentication</EventType>";
str += "<event>";
str += "<UserPin>12345</UserPin>";
str += "<DeviceId>12345</DeviceId>";
str += "<DeviceSer>ABCDE</DeviceSer>";
str += "<DeviceVer>ABCDE</DeviceVer>";
str += "<TransType>Users</TransType>";
str += "</event></request>";
bw.write(str);
bw.flush();
System.out.println("Message sent to the server......! ");
//Get the return message from the server
InputStream is = socket.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
}
catch (Exception exception)
{
exception.printStackTrace();
}
finally
{
//Closing the socket
try
{
socket.close();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
You can use this code to store results from server in file
//Get the return message from the server
InputStream is = socket.getInputStream();
OutputStream outputStream = new FileOutputStream(new File("ReadMe.txt"));
int read = 0;
byte[] bytes = new byte[1024];
while ((read = inputStream.read(bytes)) != -1) {
outputStream.write(bytes, 0, read);
}
This question already has answers here:
How do I send file name with file using sockets in Java? [duplicate]
(3 answers)
Closed 6 years ago.
I am able to send Files through socket and receive on other ends . Now i want to send even file name so that after receiving file and saving file from socket i can save the name of file. What to add in client to send filename and in server to receive filename thanks in advance to all
Client.java
try {
clientSocket = new Socket(targetIP, port);
os = clientSocket.getOutputStream();
PrintWriter pw = new PrintWriter(os);
InputStream is = clientSocket.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
signalActivity("About to start handshake");
byte[] buffer = new byte[4096];
FileInputStream fis = new FileInputStream(fileToSend);
BufferedInputStream bis = new BufferedInputStream(fis);
// long BytesToSend = fileToSend.length();
while(true)
{
int bytesRead = bis.read(buffer, 0, buffer.length);
if(bytesRead == -1)
{
break;
}
//BytesToSend = BytesToSend - bytesRead;
os.write(buffer,0, bytesRead);
os.flush();
}
fis.close();
bis.close();
br.close();
isr.close();
is.close();
pw.close();
os.close();
clientSocket.close();
} catch (IOException e) {
}
catch(Exception e)
{
}
Server.java
try {
welcomeSocket = new ServerSocket(port);
while(true && serviceEnabled)
{
socket = welcomeSocket.accept();
InputStream is = socket.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
OutputStream os = socket.getOutputStream();
PrintWriter pw = new PrintWriter(os);
String inputData = "";
// String savedAs = "WDFL_File_" + System.currentTimeMillis();
//save the original name and extention
File file = new File(saveLocation, savedAs);
byte[] buffer = new byte[4096];
int bytesRead;
FileOutputStream fos = new FileOutputStream(file);
BufferedOutputStream bos = new BufferedOutputStream(fos);
while(true)
{
bytesRead = is.read(buffer, 0, buffer.length);
if(bytesRead == -1)
{
break;
}
bos.write(buffer, 0, bytesRead);
bos.flush();
}
bos.close();
socket.close();
//Start writing to file
}
} catch (IOException e) {
}
catch(Exception e)
{
}
Your client should send the file name first. After that the contents of the file.
The server should read the file name first so the following content of the file can be saved under the same file name.
I have a server client file transfer program which works fine in java .but i copied it and changed the file location d:/ to environm.....
The problem is the filesize is lesser than sending one, hence its shown as corrupted.. Any idea .
SERVER SIDE
public class Server
{
// create socket
long start = System.currentTimeMillis();
int bytesRead;
int current = 0;
while(true)
{
ServerSocket servsock = new ServerSocket(13000);
System.out.println("Main Waiting...");
Socket socket = servsock.accept();
System.out.println("Accepted connection : " + socket);
DataInputStream in = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
long filesize = new Long(in.readLong());
System.out.println("received Size:"+filesize);
// read file name
String fname=in.readUTF();
System.out.println("server : file name: "+fname);
String prefix=fname.substring(0,fname.lastIndexOf('.')).trim();
String suffix=fname.substring(fname.lastIndexOf('.'),fname.length()).trim();
String file = prefix + suffix;
System.out.println("received name:"+file);
File f=new File("F:/Users/achu/Desktop/"+ file);// changed this in android
f.createNewFile();
// receive file
byte [] mybytearray = new byte [(int)(filesize)];
InputStream is = socket.getInputStream();
FileOutputStream fos = new FileOutputStream(f);
BufferedOutputStream bos = new BufferedOutputStream(fos);
bytesRead = is.read(mybytearray,0,mybytearray.length);
current = bytesRead;
do {
System.out.println("current"+current);
bytesRead =
is.read(mybytearray, current, (mybytearray.length-current));
if(bytesRead >= 0) current += bytesRead;
} while(current<filesize && bytesRead >-1);
bos.write(mybytearray, 0 , current);
bos.flush();
long end = System.currentTimeMillis();
System.out.println(end-start);
bos.close();
is.close();
socket.close();
servsock.close();
}
}
CLIENT SIDE
public class Client
{
Socket socket=new Socket("101.59.43.58",13000);
System.out.println("Connectedddd");
DataOutputStream out = new DataOutputStream(socket.getOutputStream());
File file = new File("d:/my.pdf");
out.writeLong(file.length());
out.flush();
out.writeUTF(file.getName());
byte [] mybytearray = new byte [(int)file.length()];
FileInputStream fis = new FileInputStream(file);
BufferedInputStream bis = new BufferedInputStream(fis);
bis.read(mybytearray,0,mybytearray.length);
System.out.println("Send:"+mybytearray.length);
OutputStream ous = socket.getOutputStream();
System.out.println("Sending...");
ous.write(mybytearray,0,mybytearray.length);
ous.flush();
bis.close();
ous.close();
System.out.println("closing socket...");
socket.close();
}
I am trying to develop a very simple client / server where the client converts a file to bytes, sends it to the server, and then converts the bytes back in to a file.
Currently the program just creates an empty file. I'm not a fantastic Java developer so any help much appreciated.
This is the server part that receives what the client sends.
ServerSocket serverSocket = null;
serverSocket = new ServerSocket(4444);
Socket socket = null;
socket = serverSocket.accept();
DataOutputStream out = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream()));
DataInputStream in = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
byte[] bytes = new byte[1024];
in.read(bytes);
System.out.println(bytes);
FileOutputStream fos = new FileOutputStream("C:\\test2.xml");
fos.write(bytes);
And here is the client part
Socket socket = null;
DataOutputStream out = null;
DataInputStream in = null;
String host = "127.0.0.1";
socket = new Socket(host, 4444);
out = new DataOutputStream(new BufferedOutputStream(socket.getOutputStream()));
in = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
File file = new File("C:\\test.xml");
//InputStream is = new FileInputStream(file);
// Get the size of the file
long length = file.length();
if (length > Integer.MAX_VALUE) {
System.out.println("File is too large.");
}
byte[] bytes = new byte[(int) length];
//out.write(bytes);
System.out.println(bytes);
out.close();
in.close();
socket.close();
The correct way to copy a stream in Java is as follows:
int count;
byte[] buffer = new byte[8192]; // or 4096, or more
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
Wish I had a dollar for every time I've posted that in a forum.
Thanks for the help. I've managed to get it working now so thought I would post so that the others can use to help them.
Server:
public class Server {
public static void main(String[] args) throws IOException {
ServerSocket serverSocket = null;
try {
serverSocket = new ServerSocket(4444);
} catch (IOException ex) {
System.out.println("Can't setup server on this port number. ");
}
Socket socket = null;
InputStream in = null;
OutputStream out = null;
try {
socket = serverSocket.accept();
} catch (IOException ex) {
System.out.println("Can't accept client connection. ");
}
try {
in = socket.getInputStream();
} catch (IOException ex) {
System.out.println("Can't get socket input stream. ");
}
try {
out = new FileOutputStream("M:\\test2.xml");
} catch (FileNotFoundException ex) {
System.out.println("File not found. ");
}
byte[] bytes = new byte[16*1024];
int count;
while ((count = in.read(bytes)) > 0) {
out.write(bytes, 0, count);
}
out.close();
in.close();
socket.close();
serverSocket.close();
}
}
and the Client:
public class Client {
public static void main(String[] args) throws IOException {
Socket socket = null;
String host = "127.0.0.1";
socket = new Socket(host, 4444);
File file = new File("M:\\test.xml");
// Get the size of the file
long length = file.length();
byte[] bytes = new byte[16 * 1024];
InputStream in = new FileInputStream(file);
OutputStream out = socket.getOutputStream();
int count;
while ((count = in.read(bytes)) > 0) {
out.write(bytes, 0, count);
}
out.close();
in.close();
socket.close();
}
}
Here is the server
Open a stream to the file and send it overnetwork
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class SimpleFileServer {
public final static int SOCKET_PORT = 5501;
public final static String FILE_TO_SEND = "file.txt";
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(SOCKET_PORT);
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.");
} catch (IOException ex) {
System.out.println(ex.getMessage()+": An Inbound Connection Was Not Resolved");
}
}finally {
if (bis != null) bis.close();
if (os != null) os.close();
if (sock!=null) sock.close();
}
}
}
finally {
if (servsock != null)
servsock.close();
}
}
}
Here is the client
Recive the file being sent overnetwork
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.Socket;
public class SimpleFileClient {
public final static int SOCKET_PORT = 5501;
public final static String SERVER = "127.0.0.1";
public final static String
FILE_TO_RECEIVED = "file-rec.txt";
public final static int FILE_SIZE = Integer.MAX_VALUE;
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(SERVER, SOCKET_PORT);
System.out.println("Connecting...");
// receive file
byte [] mybytearray = new byte [FILE_SIZE];
InputStream is = sock.getInputStream();
fos = new FileOutputStream(FILE_TO_RECEIVED);
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();
System.out.println("File " + FILE_TO_RECEIVED
+ " downloaded (" + current + " bytes read)");
}
finally {
if (fos != null) fos.close();
if (bos != null) bos.close();
if (sock != null) sock.close();
}
}
}
To avoid the limitation of the file size , which can cause the Exception java.lang.OutOfMemoryError to be thrown when creating an array of the file size byte[] bytes = new byte[(int) length];, instead we could do
byte[] bytearray = new byte[1024*16];
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
OutputStream output= socket.getOututStream();
BufferedInputStream bis = new BufferedInputStream(fis);
int readLength = -1;
while ((readLength = bis.read(bytearray)) > 0) {
output.write(bytearray, 0, readLength);
}
bis.close();
output.close();
}
catch(Exception ex ){
ex.printStackTrace();
} //Excuse the poor exception handling...
Rookie, if you want to write a file to server by socket, how about using fileoutputstream instead of dataoutputstream? dataoutputstream is more fit for protocol-level read-write. it is not very reasonable for your code in bytes reading and writing. loop to read and write is necessary in java io. and also, you use a buffer way. flush is necessary. here is a code sample: http://www.rgagnon.com/javadetails/java-0542.html
Adding up on EJP's answer; use this for more fluidity.
Make sure you don't put his code inside a bigger try catch with more code between the .read and the catch block, it may return an exception and jump all the way to the outer catch block, safest bet is to place EJPS's while loop inside a try catch, and then continue the code after it, like:
int count;
byte[] bytes = new byte[4096];
try {
while ((count = is.read(bytes)) > 0) {
System.out.println(count);
bos.write(bytes, 0, count);
}
} catch ( Exception e )
{
//It will land here....
}
// Then continue from here
EDIT: ^This happened to me cuz I didn't realize you need to put socket.shutDownOutput() if it's a client-to-server stream!
Hope this post solves any of your issues