java - how to fix this “Required arguments: dst_hostname dst_port local_port” closed -

here testserver class , clientclass everytime required arguments: dst_hostname dst_port local_port message. can fix this? ip's should write hostname.

    public static void main(string[] args) throws exception {                  if (args.length != 3)                   {                  system.out.println("required arguments: dst_hostname dst_port local_port");                  return;              }                  string hostname = args[0];              int dst_port = integer.parseint(args[1]);              int local_port = integer.parseint(args[2]);               rdt rdt = new rdt("localhost", 25566, 25566,3,3);              rdt.setlossrate(0.2);              byte[] buf = new byte[rdt.mss];                       system.out.println("\n\n ======>server waiting receive<========\n\n " );                while (true) {                  int size = rdt.receive(buf, rdt.mss);                 // system.out.println("size " + size);                  (int i=0; i<size; i++)                          system.out.print(buf[i]);                  system.out.println(" ");                  system.out.flush();              }          } } 

and here testclient class

import java.io.*; import java.net.*; import java.util.*;  public class testclient {          public testclient() {          }          public static void main(string[] args) {                  if (args.length != 3) {                  system.out.println("required arguments: dst_hostname dst_port local_port");                  return;               }                  string hostname = args[0]; //dnsnamelook ip                  int dst_port = integer.parseint(args[1]);                  int local_port = integer.parseint(args[2]);               rdt rdt = new rdt("localhost", 25566, 25566,3,3);              rdt.setlossrate(0.3);               byte[] buf = new byte[rdt.mss];  //buffer set mss              byte[] data = new byte[543]; //data               system.out.println("\n\n ======>client sending data<========\n\n " );              (int i=0; i<data.length; i++)                  data[i] = 0;              rdt.send(data, data.length);               (int i=0; i<data.length; i++)                  data[i] = 1;              rdt.send(data, data.length);               (int i=0; i<data.length; i++)                  data[i] = 2;              rdt.send(data, data.length);               (int i=0; i<data.length; i++)                  data[i] = 3;              rdt.send(data, data.length);               (int i=0; i<data.length; i++)                  data[i] = 4;              rdt.send(data, data.length);                system.out.println(system.currenttimemillis() + "\n\nclient has sent data \n\n" );              system.out.flush();               rdt.receive(buf, rdt.mss);              rdt.close();              system.out.println("client done " );         }  }