Address already used problem in Java Socket application

[Ammy Singh]

I have made a small server which accepts a client request. The code is as following.
But i am getting an error message as: Exception in thread "main" java.lang.NullPointerException
at ServerSide.main(ServerSide.java:24)
Not a priveleged Userjava.net.BindException: Address already in use: JVM_Bind



i think the problem is with the port number that i am using, but i tried different port numbers and error still exist, please help,
Regards,
Aman

   
//ServerSide.java

	import java.io.*;
	import java.net.*;
	public class ServerSide {
	    public static void main(String args[])
	    {
	    	ServerSocket serverSocket = null;
	        String line;
	        DataInputStream is;
	        PrintStream os;
	        
	        Socket clientSocket = null;
	
	        try 
	        {
	            serverSocket = new ServerSocket(1028);
	        }
	        catch (IOException e) {
	           System.out.println("Not a priveleged User" +e);
	        }   
	
	    try {
	           clientSocket = serverSocket.accept();
	           is = new DataInputStream(clientSocket.getInputStream());
	           os = new PrintStream(clientSocket.getOutputStream());
	
	           while (true) {
	             line = is.readLine();
	             os.println(line); 
	           }
	        }   
	    catch (IOException e) {
	           System.out.println(e);
	        }
	    }
	}
 

[Campbell Ritchie]

And which line is the Exception thrown from?

[Ram Narayan.M]

Port address is already in use...

[Ammy Singh]

Campbell Ritchie wrote:And which line is the Exception thrown from?

The exception is trown at following:

  serverSocket = new ServerSocket(2004, 10);  

and

   clientSocket = serverSocket.accept(); 

And the console result is as : Not a priveleged Userjava.net.BindException: Address already in use: JVM_Bind
Exception in thread "main" java.lang.NullPointerException
at ServerSide.main(ServerSide.java:22)

[Ammy Singh]

Ram Narayan.M wrote:Port address is already in use...

Ok its fine that the port address is already in use, but how can i find an unused port, and note that i am running the program on a standalone server.

[Campbell Ritchie]

Too difficult a question for "beginning Java". Moving thread.

[Ammy Singh]

Campbell Ritchie wrote:Too difficult a question for "beginning Java". Moving thread.

ok thank you next time i will take care about which thread to select.