having trouble with global variables

[cloutier172]

i cant seem to get my global variable to work. what am i doing wrong

import java.util.Scanner;

public class HW1 {
    /**
     * global credits used through out the program 
     */
    public double Credits = 0.00;
    
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        String Item[] = {"","Coke","Diet Coke","Orange","Dr Pepper","Caffeine-Free Coke",
            "Coors","Rum and Coke","Doritos","Crackers","Patch Cable","Coffie","Espresso"};
        int item[] = {0,10,10,10,10,10,10,10,10,10,10,0,10};
        double price[] = {0,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00};
        String out = "Sold Out";
        int marker = 1;
        String Card = "Insert Card";
        double CashBox = 0.00;
        int MenuSelection = 0;
        System.out.println("-----------------------------------");
        System.out.println("Welcome to Shane's Vending Machine");
        
        while( marker <= 12){
            
            if( item[marker] > 0 ){
                System.out.printf(marker+". " +Item[marker]+ " $%5.2f\n", price[marker]);
                marker ++;
            }
            else if( item[marker] == 0){
                System.out.println(+marker+". "+out);
                marker ++;
            }
        }
        marker = 1;
        
        
        System.out.printf("Current Credit: $%5.2f\n", getCredits());
        System.out.println("Card Balance: "+Card);
        System.out.println("-----------------------------------");
        while ( MenuSelection != 6){
            System.out.println("Main Menu");
            System.out.println("Deposite Coin: 1");
            System.out.println("Insert Card:   2");
            System.out.println("Purchase Item: 3");
            System.out.println("Cancel:        4");
            System.out.println("Service Mode:  5");
            System.out.println("End:           6");
            MenuSelection = input.nextInt();
           switch(MenuSelection){
                case 1: DepositeCoin(); break;
            }
        }
        
        
     
    }

    private static void DepositeCoin() {
       
                Scanner input = new Scanner(System.in);
                int Selection = 0;
                while( Selection != 5 ){
                    System.out.println("Insert 1 Dollar:     1");
                    System.out.println("Insert 1 Quarter:    2");
                    System.out.println("Insert 1 Dime:       3");
                    System.out.println("Insert 1 Nickel:     4");
                    System.out.println("Return to Main Menu: 5");
                    Selection = input.nextInt();
                    switch(Selection){
                        case 1: setCredits(getCredits() + 1.00); break;
                        case 2: setCredits(getCredits() + .25); break;
                        case 3: setCredits(getCredits() + .1); break;
                        case 4: setCredits(getCredits() + .05); break;
                    }
                    System.out.println("amount "+getCredits());
                }
            return Credits();
        
            }

    /**
     * @return the Credits
     */
    public double getCredits() {
        return Credits;
    }

    /**
     * @param Credits the Credits to set
     */
    public void setCredits(double Credits) {
        this.Credits = Credits;
    }
        }

[masijade]

What does "doesn't work" mean, exactly?

[christopherx]

private static void DepositeCoin() {
        
                Scanner input = new Scanner(System.in);
                int Selection = 0;
                while( Selection != 5 ){
                    System.out.println("Insert 1 Dollar:     1");
                    System.out.println("Insert 1 Quarter:    2");
                    System.out.println("Insert 1 Dime:       3");
                    System.out.println("Insert 1 Nickel:     4");
                    System.out.println("Return to Main Menu: 5");
                    Selection = input.nextInt();
                    switch(Selection){
                        case 1: setCredits(getCredits() + 1.00); break;
                        case 2: setCredits(getCredits() + .25); break;
                        case 3: setCredits(getCredits() + .1); break;
                        case 4: setCredits(getCredits() + .05); break;
                    }
                    System.out.println("amount "+getCredits());
                }
            return Credits();
         
            }

First problem i noticed was with this. Give this a look. Hint: The problem is solvable at the very start of the method, or at the very end.

[sunde887]

Java does not have global variables per se. The closes thing to them are constants, which are static and final, and probably not what you need. If you aren't going to go full oop, be cautious about using instance variables as 'global' variables.