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Exception in thread "main" java.net.SocketException: Broken pipe ???

Hello Experts,

I need your assistance about the following problem which occurs during the communication of the server and the client

Exception in thread "main" java.net.SocketException: Broken pipe
      at java.net.SocketOutputStream.socketWrite0(Native Method)
      at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
      at java.net.SocketOutputStream.write(SocketOutputStream.java:115)
      at java.io.DataOutputStream.write



Thanks in advance for any assistance !
//Server code:
 
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;
import java.util.Vector;
 
public class ClientServerMsg {
 
	static final int LISTENING_PORT = 1025;
 
	public static void main(String[] args) throws Exception {
 
		ServerSocket listener;
		listener = new ServerSocket(LISTENING_PORT);
		System.out.println("Port: " + LISTENING_PORT);
		while (true) {
			Socket connection = listener.accept();
			new ConnectionHandler(connection);
		}
 
	}
 
	static class ConnectionHandler extends Thread {
 
		int MAX = 10;
		Vector msgsList = new Vector();
 
		Socket connection;
		PrintWriter out;
		//out = System.out;
		
		private OutputStream outputstream;
		
		  ConnectionHandler(Socket conn) throws IOException {
	            connection = conn;
	            outputstream = conn.getOutputStream();
	            out = new PrintWriter(outputstream, true);
	            start();
	        }
		/*
		ConnectionHandler(Socket conn) {
			connection = conn;
			start();
		}
		*/
 
		void sendPOSTMESSAGE(String msg) throws Exception {
			try {
				if (msgsList.size() < MAX) {
					msgsList.addElement(msg);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			} catch (Exception ex) {
				out.println("ERROR");
				out.flush();
			}
 
			if (out.checkError())
				throw new Exception("Error while receiving the message");
		}
 
		void sendREADMESSAGE() throws Exception {
			if (msgsList.size() == 0) {
				out.println("ERROR");
				out.flush();
			} else if (msgsList.size() > 0) 
			{
				for (int i = 0; i < msgsList.size(); i++) {
					if (((String) msgsList.elementAt(i)).startsWith("URGENT:")) {
						out.write((String) msgsList.elementAt(i));
						msgsList.remove(i);
					} else {
						out.write((String) msgsList.elementAt(0));
						msgsList.remove(0);
					}
				}
			} else {
				if (out.checkError())
					throw new Exception("Error");
			}
		}
 
		void sendREMOVEMESSAGE(String remvmsg) throws Exception {
			for (int i = 0; i < msgsList.size(); i++) {
				if (((String) msgsList.elementAt(i)).equals(remvmsg)) {
					msgsList.remove(i);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			}
		}
 
		void sendQUIT() throws Exception {
			out.close();
			connection.close();
		}
 
		public void run() {
 
			String command = "";
			try {
				InputStream instream = null;
				try {
					instream = connection.getInputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
				Scanner in = new Scanner(instream);
				try {
					outputstream = connection.getOutputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
				//command = in.nextLine();
				if (in.hasNextLine()) {
					command = in.nextLine();
				}
				if (command.startsWith("POSTMESSAGE")) {
					try {
						sendPOSTMESSAGE(command);
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else if (command.equals("READMESSAGE")) {
					try {
						sendREADMESSAGE();
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else if (command.startsWith("REMOVEMESSAGE")) {
					try {
						sendREMOVEMESSAGE(command);
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else if (command.equals("QUIT")) {
					try {
						sendQUIT();
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else {
					out.println("UNKNOWN COMMAND");
					out.flush();
				}
			} finally {
				try {
					connection.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
 
	}
 
}
 
 
 
//Client code:
 
import java.io.*;
import java.net.*;
 
public class Client {
 
	public static void main(String argv[]) throws Exception
	{
		String sentence;
		String modifiedSentence;
		String hostname;
		int portNumber;
		String portString;
 
		BufferedReader inFromUser =
			new BufferedReader(new InputStreamReader(System.in));
		System.out.println("What host would you like to connect to?");
		hostname = inFromUser.readLine();
		
		System.out.println("What port would you like to connect to?");
		portString = inFromUser.readLine();
 
		portNumber = Integer.parseInt(portString);
 
		System.out.println("Connecting to port "+ portNumber+ " of "+ hostname +"....\n");
		Socket clientSocket = new Socket(hostname, portNumber);
 
		DataOutputStream outToServer =
			new DataOutputStream(clientSocket.getOutputStream());
 
		BufferedReader inFromServer =
			new BufferedReader(new
					InputStreamReader(clientSocket.getInputStream()));
 
		System.out.println("Connection establised");
 
 
		sentence = inFromUser.readLine();
		while (sentence != null)
		{
			/* send the sentence to the server */
		        outToServer.writeBytes(sentence + '\n'); 
			/* read response from the server */
			modifiedSentence = inFromServer.readLine();
			
			outToServer.flush();
		}
 
		clientSocket.close();
 
	}
}

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Java
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Last Comment
perdoname_
Avatar of CEHJ
CEHJ
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Make sure you aren't writing to a stream/socket that's been closed. As i mentioned before, you don't want to be using DataOutputStream but PrintWriter
Avatar of perdoname_
perdoname_

ASKER

Thanks to you the Server works fine but after each message the connections stops and prints the above error :S 
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
 
import java.net.ServerSocket;
import java.net.Socket;
 
import java.util.Scanner;
import java.util.Vector;
 
 
/**
 * DOCUMENT ME!
 *
 * @author $author$
 * @version $Revision$
  */
public class ClientServerMsg {
	static final int LISTENING_PORT = 1025;
 
	public static void main(String[] args) throws Exception {
		ServerSocket listener;
		listener = new ServerSocket(LISTENING_PORT);
		System.out.println("Port: " + LISTENING_PORT);
 
		while (true) {
			Socket connection = listener.accept();
			new ConnectionHandler(connection);
		}
	}
 
	static class ConnectionHandler extends Thread {
		int MAX = 10;
		Vector msgsList = new Vector();
		Socket connection;
		PrintWriter out = new PrintWriter(System.out); //For standard output
		private OutputStream outstream;
 
		ConnectionHandler(Socket conn) {
			connection = conn;
			start();
		}
 
		void sendPOSTMESSAGE(String msg) throws Exception {
			try {
				if (msgsList.size() < MAX) {
					msgsList.addElement(msg);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			} catch (Exception ex) {
				out.println("ERROR");
				out.flush();
			}
 
			if (out.checkError()) {
				throw new Exception("Error while receiving the message");
			}
		}
 
		void sendREADMESSAGE() throws Exception {
			if (msgsList.size() == 0) {
				out.println("ERROR");
				out.flush();
			} else if (msgsList.size() > 0) {
				for (int i = 0; i < msgsList.size(); i++) {
					if (((String) msgsList.elementAt(i)).startsWith("URGENT:")) {
						out.write((String) msgsList.elementAt(i));
						msgsList.remove(i);
					} else {
						out.write((String) msgsList.elementAt(0));
						msgsList.remove(0);
					}
				}
			} else {
				if (out.checkError()) {
					throw new Exception("Error");
				}
			}
		}
 
		void sendREMOVEMESSAGE(String remvmsg) throws Exception {
			for (int i = 0; i < msgsList.size(); i++) {
				if (((String) msgsList.elementAt(i)).equals(remvmsg)) {
					msgsList.remove(i);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			}
		}
 
		void sendQUIT() throws Exception {
			out.close();
			connection.close();
		}
 
		public void run() {
			String command = "";
 
			try {
				InputStream instream = null;
 
				try {
					instream = connection.getInputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
 
				Scanner in = new Scanner(instream);
 
				try {
					outstream = connection.getOutputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
 
				//command = in.nextLine();
				if (in.hasNextLine()) {
					command = in.nextLine();
				}
 
				if (command.startsWith("POSTMESSAGE")) {
					try {
						sendPOSTMESSAGE(command);
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else if (command.equals("READMESSAGE")) {
					try {
						sendREADMESSAGE();
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else if (command.startsWith("REMOVEMESSAGE")) {
					try {
						sendREMOVEMESSAGE(command);
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else if (command.equals("QUIT")) {
					try {
						sendQUIT();
					} catch (Exception e) {
						e.printStackTrace();
					}
				} else {
					out.println("UNKNOWN COMMAND");
					out.flush();
				}
			} finally {
				try {
					connection.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
}

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Avatar of CEHJ
CEHJ
Flag of United Kingdom of Great Britain and Northern Ireland image
Your server simply reads the message, echos it, then closes. Don't you want it to respond continously? If so, you need to loop in run()
Avatar of perdoname_
perdoname_

ASKER

I've added a while (true) but that leads again to:
Exception in thread "main" java.net.SocketException: Broken pipe
      at java.net.SocketOutputStream.socketWrite0(Native Method)
      at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
      at java.net.SocketOutputStream.write(SocketOutputStream.java:115)
      at java.io.DataOutputStream.writeBytes(DataOutputStream.java:259)
      at Client.main(Client.java:41)


plus that:

java.net.SocketException: Socket is closed
      at java.net.Socket.getInputStream(Socket.java:766)
      at ClientServerMsg$ConnectionHandler.run(ClientServerMsg.java:112)
Exception in thread "Thread-0" java.lang.NullPointerException
      at java.io.Reader.<init>(Reader.java:61)
      at java.io.InputStreamReader.<init>(InputStreamReader.java:55)
      at java.util.Scanner.<init>(Scanner.java:575)
      at ClientServerMsg$ConnectionHandler.run(ClientServerMsg.java:117)

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
 
import java.net.ServerSocket;
import java.net.Socket;
 
import java.util.Scanner;
import java.util.Vector;
 
 
/**
 * DOCUMENT ME!
 *
 * @author $author$
 * @version $Revision$
 */
public class ClientServerMsg {
	static final int LISTENING_PORT = 1025;
 
	public static void main(String[] args) throws Exception {
		ServerSocket listener;
		listener = new ServerSocket(LISTENING_PORT);
		System.out.println("Port: " + LISTENING_PORT);
 
		while (true) {
			Socket connection = listener.accept();
			new ConnectionHandler(connection);
		}
	}
 
	static class ConnectionHandler extends Thread {
		int MAX = 10;
		Vector msgsList = new Vector();
		Socket connection;
		PrintWriter out = new PrintWriter(System.out); //For standard output
		private OutputStream outstream;
 
		ConnectionHandler(Socket conn) {
			connection = conn;
			start();
		}
 
		void sendPOSTMESSAGE(String msg) throws Exception {
			try {
				if (msgsList.size() < MAX) {
					msgsList.addElement(msg);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			} catch (Exception ex) {
				out.println("ERROR");
				out.flush();
			}
 
			if (out.checkError()) {
				throw new Exception("Error while receiving the message");
			}
		}
 
		void sendREADMESSAGE() throws Exception {
			if (msgsList.size() == 0) {
				out.println("ERROR");
				out.flush();
			} else if (msgsList.size() > 0) {
				for (int i = 0; i < msgsList.size(); i++) {
					if (((String) msgsList.elementAt(i)).startsWith("URGENT:")) {
						out.write((String) msgsList.elementAt(i));
						msgsList.remove(i);
					} else {
						out.write((String) msgsList.elementAt(0));
						msgsList.remove(0);
					}
				}
			} else {
				if (out.checkError()) {
					throw new Exception("Error");
				}
			}
		}
 
		void sendREMOVEMESSAGE(String remvmsg) throws Exception {
			for (int i = 0; i < msgsList.size(); i++) {
				if (((String) msgsList.elementAt(i)).equals(remvmsg)) {
					msgsList.remove(i);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			}
		}
 
		void sendQUIT() throws Exception {
			out.close();
			connection.close();
		}
 
		public void run() {
			String command = "";
			while (true)
			{
				try {
					InputStream instream = null;
 
					try {
						instream = connection.getInputStream();
					} catch (IOException e) {
						e.printStackTrace();
					}
 
					Scanner in = new Scanner(instream);
 
					try {
						outstream = connection.getOutputStream();
					} catch (IOException e) {
						e.printStackTrace();
					}
 
					//command = in.nextLine();
					if (in.hasNextLine()) {
						command = in.nextLine();
					}
 
					if (command.startsWith("POSTMESSAGE")) {
						try {
							sendPOSTMESSAGE(command);
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.equals("READMESSAGE")) {
						try {
							sendREADMESSAGE();
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.startsWith("REMOVEMESSAGE")) {
						try {
							sendREMOVEMESSAGE(command);
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.equals("QUIT")) {
						try {
							sendQUIT();
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else {
						out.println("UNKNOWN COMMAND");
						out.flush();
					}
				} finally {
					try {
						connection.close();
					} catch (IOException e) {
						e.printStackTrace();
					}
				}
			}
		}
	}
}

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Avatar of perdoname_
perdoname_

ASKER

Thank you very much but unfortunately there still a problem
After the first message there is no response for further messages
e.g
java Client
What host would you like to connect to?
localhost
What port would you like to connect to?
1025
Connecting to port 1025 of localhost....

Connection establised
POSTMESSAGE something
READMESSAGE
POSTMESSAGE some




java ClientServerMsg localhost 1025
Port: 1025
OK

Avatar of CEHJ
CEHJ
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I would actually include debugging messages so you can trace the execution
Avatar of perdoname_
perdoname_

ASKER

I didn't understand what do you mean :S
Avatar of CEHJ
CEHJ
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System.out.println("This is a debugging message");
Avatar of perdoname_
perdoname_

ASKER

And how this will make the application to run with no problems :S ? ?
Avatar of CEHJ
CEHJ
Flag of United Kingdom of Great Britain and Northern Ireland image
It won't. It will help you find out why it's not doing so
Avatar of perdoname_
perdoname_

ASKER

But i cant see anything wrong in the code :S :S 
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
 
import java.net.ServerSocket;
import java.net.Socket;
 
import java.util.Scanner;
import java.util.Vector;
 
 
/**
 * DOCUMENT ME!
 *
 * @author $author$
 * @version $Revision$
 */
public class ClientServerMsg {
	static final int LISTENING_PORT = 1025;
 
	public static void main(String[] args) throws Exception {
		ServerSocket listener;
		listener = new ServerSocket(LISTENING_PORT);
		System.out.println("Port: " + LISTENING_PORT);
 
		while (true) {
			Socket connection = listener.accept();
			new ConnectionHandler(connection);
		}
	}
 
	static class ConnectionHandler extends Thread {
		int MAX = 10;
		@SuppressWarnings("unchecked")
		Vector msgsList = new Vector();
		Socket connection;
		PrintWriter out = new PrintWriter(System.out); //For standard output
		@SuppressWarnings("unused")
		private OutputStream outstream;
 
		ConnectionHandler(Socket conn) {
			connection = conn;
			start();
		}
 
		@SuppressWarnings("unchecked")
		void sendPOSTMESSAGE(String msg) throws Exception {
			try {
				if (msgsList.size() < MAX) {
					msgsList.addElement(msg);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			} catch (Exception ex) {
				out.println("ERROR");
				out.flush();
			}
 
			if (out.checkError()) {
				throw new Exception("Error while receiving the message");
			}
		}
 
		void sendREADMESSAGE() throws Exception {
			if (msgsList.size() == 0) {
				out.println("ERROR");
				out.flush();
			} else if (msgsList.size() > 0) {
				for (int i = 0; i < msgsList.size(); i++) {
					if (((String) msgsList.elementAt(i)).startsWith("URGENT:")) {
						out.write((String) msgsList.elementAt(i));
						msgsList.remove(i);
					} else {
						out.write((String) msgsList.elementAt(0));
						msgsList.remove(0);
					}
				}
			} else {
				if (out.checkError()) {
					throw new Exception("Error");
				}
			}
		}
 
		void sendREMOVEMESSAGE(String remvmsg) throws Exception {
			for (int i = 0; i < msgsList.size(); i++) {
				if (((String) msgsList.elementAt(i)).equals(remvmsg)) {
					msgsList.remove(i);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			}
		}
 
		void sendQUIT() throws Exception {
			out.close();
			connection.close();
		}
 
		public void run() {
			String command = "";
 
			try {
				InputStream instream = null;
 
				try {
					instream = connection.getInputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
 
				Scanner in = new Scanner(instream);
 
				try {
					outstream = connection.getOutputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
 
				//command = in.nextLine();
				while ("QUIT".equals(command) == false) {
					if (in.hasNextLine()) {
						command = in.nextLine();
					}
 
					if (command.startsWith("POSTMESSAGE")) {
						try {
							sendPOSTMESSAGE(command);
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.equals("READMESSAGE")) {
						try {
							sendREADMESSAGE();
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.startsWith("REMOVEMESSAGE")) {
						try {
							sendREMOVEMESSAGE(command);
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.equals("QUIT")) {
						try {
							sendQUIT();
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else {
						out.println("UNKNOWN COMMAND");
						out.flush();
					}
				}
			} finally {
				try {
					connection.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
}

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Avatar of CEHJ
CEHJ
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I would also recommend you run the server and test it with telnet, leaving the client until you know the server works as expected
Avatar of CEHJ
CEHJ
Flag of United Kingdom of Great Britain and Northern Ireland image
Also change

>>PrintWriter out = new PrintWriter(System.out); //For standard output

to

PrintWriter out = new PrintWriter(System.out, true); //For standard output
Avatar of perdoname_
perdoname_

ASKER

Still seems fine so the problem probably is logical (?)  :S 
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
 
import java.net.ServerSocket;
import java.net.Socket;
 
import java.util.Scanner;
import java.util.Vector;
 
 
/**
 * DOCUMENT ME!
 *
 * @author $author$
 * @version $Revision$
 */
public class ClientServerMsg {
	static final int LISTENING_PORT = 1025;
 
	public static void main(String[] args) throws Exception {
		ServerSocket listener;
		listener = new ServerSocket(LISTENING_PORT);
		System.out.println("Port: " + LISTENING_PORT);
 
		while (true) {
			Socket connection = listener.accept();
			new ConnectionHandler(connection);
		}
	}
 
	static class ConnectionHandler extends Thread {
		int MAX = 10;
		@SuppressWarnings("unchecked")
		Vector msgsList = new Vector();
		Socket connection;
		PrintWriter out = new PrintWriter(System.out, true); //For standard output
		@SuppressWarnings("unused")
		private OutputStream outstream;
 
		ConnectionHandler(Socket conn) {
			connection = conn;
			start();
		}
 
		@SuppressWarnings("unchecked")
		void sendPOSTMESSAGE(String msg) throws Exception {
			try {
				if (msgsList.size() < MAX) {
					msgsList.addElement(msg);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			} catch (Exception ex) {
				out.println("ERROR");
				out.flush();
			}
 
			if (out.checkError()) {
				throw new Exception("Error while receiving the message");
			}
		}
 
		void sendREADMESSAGE() throws Exception {
			if (msgsList.size() == 0) {
				out.println("ERROR");
				out.flush();
			} else if (msgsList.size() > 0) {
				for (int i = 0; i < msgsList.size(); i++) {
					if (((String) msgsList.elementAt(i)).startsWith("URGENT:")) {
						out.write((String) msgsList.elementAt(i));
						msgsList.remove(i);
					} else {
						out.write((String) msgsList.elementAt(0));
						msgsList.remove(0);
					}
				}
			} else {
				if (out.checkError()) {
					throw new Exception("Error");
				}
			}
		}
 
		void sendREMOVEMESSAGE(String remvmsg) throws Exception {
			for (int i = 0; i < msgsList.size(); i++) {
				if (((String) msgsList.elementAt(i)).equals(remvmsg)) {
					msgsList.remove(i);
					out.println("OK");
					out.flush();
				} else {
					out.println("ERROR");
					out.flush();
				}
			}
		}
 
		void sendQUIT() throws Exception {
			out.close();
			connection.close();
		}
 
		public void run() {
			String command = "";
 
			try {
				InputStream instream = null;
 
				try {
					instream = connection.getInputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
 
				Scanner in = new Scanner(instream);
 
				try {
					outstream = connection.getOutputStream();
				} catch (IOException e) {
					e.printStackTrace();
				}
 
				//command = in.nextLine();
				while ("QUIT".equals(command) == false) {
					if (in.hasNextLine()) {
						command = in.nextLine();
					}
 
					if (command.startsWith("POSTMESSAGE")) {
						try {
							sendPOSTMESSAGE(command);
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.equals("READMESSAGE")) {
						try {
							sendREADMESSAGE();
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.startsWith("REMOVEMESSAGE")) {
						try {
							sendREMOVEMESSAGE(command);
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else if (command.equals("QUIT")) {
						try {
							sendQUIT();
						} catch (Exception e) {
							e.printStackTrace();
						}
					} else {
						out.println("UNKNOWN COMMAND");
						out.flush();
					}
				}
			} finally {
				try {
					connection.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
}

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Avatar of CEHJ
CEHJ
Flag of United Kingdom of Great Britain and Northern Ireland image
Yes, it probably is
Avatar of perdoname_
perdoname_

ASKER

Have you got any ideas what might be the problem ?
Avatar of CEHJ
CEHJ
Flag of United Kingdom of Great Britain and Northern Ireland image
It seems to work fine for me using telnet
Avatar of perdoname_
perdoname_

ASKER

So the problem is in the client ??
//Client:
 
import java.io.*;
import java.net.*;
 
public class Client {
 
	public static void main(String argv[]) throws Exception
	{
		String sentence;
		String modifiedSentence = null;
		String hostname;
		int portNumber;
		String portString;
 
		BufferedReader inFromUser =
			new BufferedReader(new InputStreamReader(System.in));
		System.out.println("What host would you like to connect to?");
		hostname = inFromUser.readLine();
 
		System.out.println("What port would you like to connect to?");
		portString = inFromUser.readLine();
 
		portNumber = Integer.parseInt(portString);
 
		System.out.println("Connecting to port "+ portNumber+ " of "+ hostname +"....\n");
		Socket clientSocket = new Socket(hostname, portNumber);
 
		DataOutputStream outToServer =
			new DataOutputStream(clientSocket.getOutputStream());
 
		BufferedReader inFromServer =
			new BufferedReader(new
					InputStreamReader(clientSocket.getInputStream()));
 
		System.out.println("Connection establised");
 
 
	    sentence = inFromUser.readLine();
            while (sentence != null)
            {
                  /* send the sentence to the server */
                    outToServer.writeBytes(sentence + '\n');
                  /* read response from the server */
                  modifiedSentence = inFromServer.readLine();
                  
                  outToServer.flush();
            }
 
 
		clientSocket.close();
 
	}
}

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Avatar of CEHJ
CEHJ
Flag of United Kingdom of Great Britain and Northern Ireland image
Probably, yes. I gather you're now dealing with that in another question
Avatar of perdoname_
perdoname_

ASKER

If you could also be some assistance about the client problem would be more than grateful !
Java
Java

Java is a platform-independent, object-oriented programming language and run-time environment, designed to have as few implementation dependencies as possible such that developers can write one set of code across all platforms using libraries. Most devices will not run Java natively, and require a run-time component to be installed in order to execute a Java program.

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