Please help me debug the socket code

[Tarun Mendon]

I created 2 files Client.java and Server.java and i tried to send the data using sockets to Server side and display it.
But I am getting a Run-time exception.
Please help
The code along with the output(within comments) is displayed below.


Client.java:-
==============================
import java.net.*;
import java.io.*;
class Client
{
public static void main(String args[])
{
Socket s=null;
PrintWriter out=null;
try{
s=new Socket("127.0.0.1",8088);
}
catch(UnknownHostException e)
{
System.out.println("E1:"+e);
}
catch(IOException e)
{
System.out.println("E2:"+e);
}


BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

System.out.println("Enter data:");
try{
String str=br.readLine();

out =new PrintWriter(s.getOutputStream());

out.println(str);

}
catch(IOException e)
{System.out.println("E3:"+e);}








}
}


/*Output:-
C:\Tarun\java\Network>java Client
Enter data:
hello

*/

Server.java:-
===============================================

import java.net.*;
import java.io.*;
class Server
{
public static void main(String args[])
{
ServerSocket s=null;
Socket clientconn=null;
BufferedReader br=null;
String s1="";
try{
s=new ServerSocket(8088);
clientconn=s.accept();
System.out.println(clientconn.getInetAddress());
System.out.println(clientconn.getLocalPort());
}
catch(IOException e)
{
System.out.println("E1:"+e);
}


try{
String str="";
br=new BufferedReader(new InputStreamReader(clientconn.getInputStream()));
System,.out.println(br);
s1=br.read();
System.out.println(br.readLine());
}
catch(IOException e)
{
System.out.println("E2:"+e+" String s1:"+s1);
}





}
}

/*Output:-
C:\Tarun\java\Network>java Server
/127.0.0.1
8088
E2:java.net.SocketException: Connection reset String s1:
*/

[Vyas Sanzgiri]

Is this the correct forum???

[Andrew Monkhouse]

Nope. Moved to the Sockets forum.

[Rob Spoor]

Tarun, please use code tags.

[Ulf Dittmer]

Not sure what's going on, but you should read this article: Don't println to a Socket

[Ernest Friedman-Hill]

I see a couple of obvious problems here. First, neither of these lines:

System,.out.println(br);
s1=br.read(); 

will compile, as the first line has that extra comma, and in the second, the "int" returned by read() can't be assigned to s1, which is a String. So you're not showing us the actual code which caused the error; that makes it harder to diagnose the problem!

But in any case, I think what's happening is that your client writes to the socket and exits without closing the connection properly. Output buffered on the client side can get dropped without being sent, and indeed, the connection can simply disappear from the server's perspective, which could give the "Connection reset" error. You need to explicitly close "out" in the client when you're done with it:

out.println(str); 
out.close();

The link Ulf gives is a good one, although it probably won't matter until you try to use sockets to connect from one platform to another. In this toy program on one machine, it won't be a problem.