Програмка "Банкомат"

import java.util.Scanner;
import java.io.*;
 
 
class Card{
 
           public String name;
           public double balance, balanceA, balanceD;
           public int menu;
           Scanner sc = new Scanner(System.in);
 
            
      Card(){
             name = "";
             balance = 0;
        }
        
      public void info(){
      System.out.print("\nCard holder: "+name);
      System.out.print("\nBalance on card: "+balance);
      System.exit(0);
      //mainmenu();
      }
      
      public double update (){
      Scanner sc = new Scanner(System.in);
      System.out.print("Updating balance for: "+name+"\nAdd balance: ");
      balanceA = sc.nextDouble();
      balance = balance + balanceA;
      System.out.print("Balance of card holder "+name+" successfully changed to "+balance);
      
      return  balance;
      }
      
      public double decrease (){
      System.out.print("Updating balance for: "+name+"\nDec balance: ");
      balanceD = sc.nextDouble();
      if(balanceD>balance){System.out.print("You make a mistake.\nPlease, try again.\n"); decrease();}else{
      balance = balance - balanceD;
      System.out.print("Balance of card holder "+name+" successfully changed to "+balance);}
      
      return  balance;
      }
      
      public double currency(double usd){
      return balance = balance / usd;
      }
      
      public int mainmenu(){
      System.out.print("\nFor continue work with system input:\n");
      System.out.print("0 - For exit\n1 - For get information\n2 - For update balance\n3 - For the decrease balance.\n4 - For the currency conversion.\n");
      System.out.print("5 - Cash withdrawal\n");      
      return menu = sc.nextInt();
      }
}
 
public class Task3{
       public static void main(String[] args) throws IOException{
       
       Card c = new Card();
       Scanner sc = new Scanner(System.in);
       BufferedReader inp = new BufferedReader(new InputStreamReader(System.in));
       String input;
       
       do{
       System.out.print("\nWelcome to the program!\nInput 'yes' to continue work and 'exit', to exit in the program: ");
       input = inp.readLine();
       if(input.equals("exit") || input.equals("Exit")){System.out.print("You came out of the program!");
                                System.exit(0);}
       } while (!input.equals("yes") && !input.equals("Yes"));
       
       
       System.out.print("\n\nEnter the name of the card holder: ");
       c.name = inp.readLine();
       System.out.print("Enter the start balance (optional): ");
       do{
       c.balance = sc.nextDouble();
       if(c.equals(""))c.balance=0;
       }
       while(c.equals(""));
       
       c.mainmenu();
       
       switch(c.menu){
       
       case 0:System.out.print("You came out of the program!");System.exit(0);break;
       case 1:c.info(); break;
       case 2:c.update();break;
       case 3:c.decrease();break;
       case 4:c.currency(10300); System.out.print("You balance in USD: "+c.balance);break;
       case 5:System.out.print("Menu for Card");break;
       default: System.out.print("Error!\nSession close.\n");
       
       }
       
       }
 
}