java - 从java中的csv列添加: how do I reset variable total?

Question

正如标题所示，我正在尝试获取 3 个单独的总计(每个 empID 一个)和一个 grandTotal；

import java.util.*;
import java.io.*;
public class SalesReport{

    public static void main(String[] args)throws IOException{
        File f = new File("sales.csv");
        Scanner in = new Scanner(f);
        int empID = 0;
        double sales = 0.0;
        double total = 0.0;
        double allTotal = 0.0;
        System.out.println("Brewster's Used Cars, Inc.\nSales Report\n\nSalesperson ID\t\tSales Amount");
        for(int i = 0;i<43;i++){
            System.out.print("≡");
        }
        System.out.print("\n");
        while(in.hasNext()){
            String data = in.next();
            String[] field = data.split(",");
            sales = Double.parseDouble(field[1]);
            if(empID == 0){
                empID = Integer.parseInt(field[0]);
            }
            if(Integer.parseInt(field[0])!=empID){
                System.out.printf("Total sales for this salesperson: $%,3.2f\n", total);
                empID = Integer.parseInt(field[0]);
                total += sales;
            }
            else{
                total += sales;
            }
            System.out.printf(empID + "\t\t\t$%,3.2f\n", sales);
        }
        allTotal += total;
        System.out.printf("Total sales for this salesperson: $%,3.2f\n", total);
        System.out.printf("Total of all sales: $%,3.2f\n", allTotal);
        in.close();
    }
}

此输出:

Brewster's Used Cars, Inc.
Sales Report

Salesperson ID          Sales Amount
≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡
100                     $10,000.00
100                     $12,000.00
100                     $5,000.00
Total sales for this salesperson: $27,000.00
101                     $14,000.00
101                     $18,000.00
101                     $12,500.00
Total sales for this salesperson: $71,500.00
102                     $13,500.00
102                     $14,500.00
102                     $20,000.00
Total sales for this salesperson: $119,500.00
Total of all sales: $119,500.00.

我尝试将 total = 0.0; 添加到第二个 if 语句，将前 2 个总计变为 0，尽管第三个是正确的。所以问题是，我如何获得这一大堆代码来计算个人的总数和销售总额？

Answer 1

在第二个 if(读取 if(Integer.parseInt(field[0])!=empID))中，尝试设置 total = sales 而不是 总计 += 销售额 就像现在一样。

在 Java 中，使用 = 为变量赋值，使用 += 为现有变量添加附加值。