//In this program, just simply demonstrate how remote methods 
//are called. there are four methods add, subtract, time and divide
//that are resided in different server respectly. Client can invoke
//all of them. 

import java.lang.*;
import java.io.*;
import java.rmi.*;

public class calClient { 
       
public static void main(String arg[]){
    int a=0, b=0;
    String ss=null;
    String newLine = System.getProperty("line.separator"); 
    try{
     addInterface ai=(addInterface)Naming.lookup("addserver");
     subtractInterface si=(subtractInterface)Naming.lookup("subtractserver");
     timeInterface ti=(timeInterface)Naming.lookup("timeserver");
     divideInterface di=(divideInterface)Naming.lookup("divideserver");
     while(true){
     System.out.println("Enter equation to calculate or quit to exit");
     BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
     String s=(br.readLine()).trim();
     if(s.trim().equals("quit")){
       br.close();
       break;
     }
 
     else{  
       int i=0;
       while(i<s.length() && Character.isDigit(s.charAt(i)))
          i=i+1;
       String s1=s.substring(0, (i));
       String s2=s.substring((i+1), s.length());
       a=Integer.parseInt(s1);
       b=Integer.parseInt(s2);
       if (s.charAt(i)=='+'){
          ss=ai.add(a,b);  //call remote method
       }
       if (s.charAt(i)=='-'){
          ss=si.subtract(a,b);  //call remote method
       }
       if (s.charAt(i)=='*'){
          ss=ti.time(a,b);  //call remote method
       }
       if (s.charAt(i)=='/'){
          ss=di.divide(a,b);  //call remote method
       }//end of if
       System.out.println(ss);
     } //end of while
    }
  } catch (NotBoundException e){
     System.out.println("Catch NotBoundException error.");
     System.exit(0);
   } catch (ArithmeticException e){
       System.out.println("Catch divide by zero error:"+e);
  } catch (RemoteException e) {
     System.out.println("Catch error:" +e);
     System.exit(0);
  } catch (java.net.MalformedURLException e){
     System.out.println("URL error:"+e);
     System.exit(0);
  }catch (IOException e){
     System.out.println("Catch IOException error.");
  }
}


}