使用增强的 for 循环打印来自用户的输入并更新变量

Question

Whenever the inputs for the my static variable total are entered by the user it will not update by adding the next input to it using +=, instead it seems to add the two together giving me double the amount. I thought of using a regular for loop under the enhanced for loop to iterate the static variable but I that did not work either.

    while(isRunning) {
      try {
        System.out.println("Please enter the name of your item you want to add: (type quit to exit) ");
          String item = input.nextLine();

        if(item.equalsIgnoreCase("quit")) {
          break;
        }
        System.out.println("Please enter the price of the item to be added to the invoice. ");
          receipt.setTotal(input.nextDouble());
          input.nextLine();
          itemList itemlist = new itemList(item, Invoice.total);
          price.add(itemlist);

      } catch (InputMismatchException e) {
        System.out.println("Exception caught!");
      }

      for(Invoice itemization : price) {
        Invoice.total += itemization.getTotal();
        System.out.println();
        System.out.println("Item: " + itemization.getItem() + "\nPrice: " + itemization.getTotal());
        System.out.println("Subtotal: " + Math.round(receipt.getTotal() * 100.00) / 100.00);

}



import java.util.*;

public class Invoice {

  static Double total;
  public String item;
  List<Invoice> price = new ArrayList<>();

  public String getItem() {
    return item;
  }

  public double getTotal() {
    return total;
  }

  public void setTotal(Double total) {
    Invoice.total = total;
  }

  public void endBalance() {

    if (getTotal() > 0.0) {
    System.out.println();
    System.out.println("$" + getTotal() + " Will be deposited once cleared. ");
    System.out.println();
    System.out.println("Expect most transfer to deposit to your account with 3 to 5 business days. ");
    System.out.println();

    } else {
      System.out.println("Available balance too low for bank deposit. ");
    }
  }

  // @Override
  // public String toString() {
  // //   return receipt.toString;
  // }
}

class itemList extends Invoice {

  public itemList(String item, Double total) {
    this.item = item;



  }

}

Answer 1

As Invoice 's getTotal() method returns the value of the static variable, Invoice.total += itemization.getTotal(); is effectively a Invoice.total *= 2; . What did you expect?