Client/Server string comunication problem

[Pedro Neves]

hello. I'm experiencing some problems with sockets.

I'm trying to make a concurrent server to accept more than one clients.

When a client connects to the server, the server creates a new thread and listens to the socket.
Then, if the client sends something, the server must read it.

On the client i just open a dictionary (txt form) and i send it over the socket.

The problem is that when i read the content of the socket (on the server side) it throws the following exception:

java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:189)
at java.net.SocketInputStream.read(SocketInputStream.java:121)
at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:283)
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:325)
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:177)
at java.io.InputStreamReader.read(InputStreamReader.java:184)
at java.io.BufferedReader.fill(BufferedReader.java:154)
at java.io.BufferedReader.readLine(BufferedReader.java:317)
at java.io.BufferedReader.readLine(BufferedReader.java:382)
at RunnableThread.run(RunnableThread.java:38)
at java.lang.Thread.run(Thread.java:722)
at RunnableThread.<init>(RunnableThread.java:16)
at KnockKnockServer.main(KnockKnockServer.java:56)


where line 38 is " s = brIn.readLine(); "



the code is (just to document my statements):


SERVER

import java.net.*;
import java.io.*;
 
public class KnockKnockServer 
{
    public static void main(String[] args) throws IOException 
    {
 
        ServerSocket serverSocket = null;
        RunnableThread rt;
        
        try { serverSocket = new ServerSocket(4443);} 
        catch (IOException e) 
        {
            System.err.println("Could not listen on port: 4443.");
            System.exit(1);
        }
 
        Socket clientSocket = null;
        try 
        { 
        	
        	clientSocket = serverSocket.accept();
        	rt = new RunnableThread("t1",clientSocket);
        } 
        catch (IOException e)
        {
            System.err.println("Accept failed.");
            System.exit(1);
        }
 
        serverSocket.close();
    }
}




import java.net.*;
import java.io.*;

class RunnableThread implements Runnable 
{

	Thread runner;
	Socket skt;

	public RunnableThread(String threadName,Socket cliSock) 
	{
		runner = new Thread(this, threadName); // (1) Create a new thread.
	
		
		skt = cliSock;
		runner.run();
	}
	@SuppressWarnings("deprecation")
	public void run() 
	{
		
		//Display info about this particular thread
		//System.out.println(Thread.currentThread());
		
		//PrintWriter out = new PrintWriter(skt.getOutputStream(), true);
		BufferedReader brIn;
        String s;
		
        
		try
		{
			s = new String();
			brIn = new BufferedReader(new InputStreamReader(skt.getInputStream()));
			
			
			while(s != null)
			{
				
				s = brIn.readLine();
				System.out.println(s);
				
			}

		} 
		catch (IOException e1) {e1.printStackTrace();	 }

	}
}

CLIENT

import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.Scanner;


public class Client 
{
	
 	
 	 public static void main(String[] args) throws IOException 
     {
 		Socket Skt;
 	 	String message,socketStr,file = new String("StressTextFile.txt");
 	 	Scanner sc = new Scanner(System.in);
 	 	
 	 	
 		System.out.println("ADDR# >>  ");
 		socketStr = sc.next();
 		Skt = new Socket(socketStr, 4443);
 		PrintWriter pwOut = new PrintWriter(Skt.getOutputStream(), true);
 		

 		 
 		 try
 		 {
 			  // Open the file that is the first 
 			  // command line parameter
 			 
 		
 			 FileInputStream fstream = new FileInputStream(file);
 			  // Get the object of DataInputStream
 			 DataInputStream in = new DataInputStream(fstream);
 			 BufferedReader br = new BufferedReader(new InputStreamReader(in));
 			 String strLine = new String();
 			 
 			  //Read File Line By Line
 			
	 			do
	 			{
	 				strLine = in.readLine();  // reads from file
	 				System.out.println(strLine);
	 				pwOut.write(new String(strLine));
	 				pwOut.flush();
	 				
	 			}while(br.readLine() != null);
	 			
	 			
	 			
 				
 			  }catch (Exception e){  System.err.println("Error: " + e.getMessage());  }
 		 
 	
     }
}

I just want to send the content of the file to the server side (which are just strings). I think my code its all right but it stills keep throwing that exception no matter what i do.

Thanks in advance.


Kind regards

[Jeff Verdegan]

It works fine for me. It reads the contents of the file, sends them to the server, which prints them out. Then the client exits without cleanly closing the socket so the server gives the exception, as expected.

As a side note, none of your new String(...)s are necessary.

[Pedro Neves]

Jeff Verdegan wrote:It works fine for me. It reads the contents of the file, sends them to the server, which prints them out. Then the client exits without cleanly closing the socket so the server gives the exception, as expected.

As a side note, none of your new String(...)s are necessary.

Well if i run it i get:

ADDR# >>
localhost

Error: null


i debugged the server put a break point on lines:
s = brIn.readLine();
System.out.println(s);

and it stucks on the first one for once, then it never stops on this lines again.

This is stupid... it works with you but but not with me? What the Hell.


Kind regards

[Pedro Neves]

Jeff Verdegan wrote:It works fine for me. It reads the contents of the file, sends them to the server, which prints them out. Then the client exits without cleanly closing the socket so the server gives the exception, as expected.

As a side note, none of your new String(...)s are necessary.

Ah.. and if it was printing was (i think) because i forget the System.out.println(strLine); :-/