import java.net.*; 
public class helbig2 { 
public static void main(String[] arg) throws Exception { 
ServerSocket serverSocket = new ServerSocket(); 
InetSocketAddress inetSocketAddress = new InetSocketAddress(InetAddress. 
getByName("127.0.0.1"), 0); 
serverSocket.bind(inetSocketAddress, 0); 
int port=serverSocket.getLocalPort(); 
Socket socket = new Socket(); 
socket.connect(new InetSocketAddress("127.0.0.1", port), 500); 
} 
}