Question

继承我的代码后，评论总结了该计划的目的。

// This program will read in from a file a number that tells how many
// wages and hours worked the file contain. And then calculates the
// salary
import java.util.*;
import java.text.*;

public class Lab10
{
        public static void main(String[] args)
        {
          // Declare variables
          Scanner scan = new Scanner(System.in);
          DecimalFormat fmt = new DecimalFormat("0.00");
          String name;
          double wages;
          double hoursWorked;
          double salary;
          int numCalculate;
          int EmployeeNumber ;
          int i = 0 ;

          // Read in how many employees the file contains
          EmployeeNumber =scan.nextInt() ;

          // for loop that reads and records the name hoursworked and wages , and prints out the information
          for ( ; i < EmployeeNumber +1; i ++ )
          {
           name = scan.next () ;
           wages = scan.nextDouble() ;
           hoursWorked = scan.nextDouble() ;

           salary = calculateSalary(wages,hoursWorked) ;
           System.out.println(name +" worked " +fmt.format(hoursWorked) + " with a wage of " + "$" +fmt.format(wages) + " and got paid $" +fmt.format(salary) );
          }
          // End of control loop

         } // End of main method

         public static double calculateSalary(double wages, double hoursWorked)
         {
//Declare constants
          final int OVERTIME_BREAK = 40;
          final double OVERTIME_MULTIPLE = 1.5;
          double salary = 0 ;

          //Calculate salary

          if(hoursWorked > OVERTIME_BREAK)
          {
          salary = (hoursWorked - OVERTIME_BREAK) * wages * OVERTIME_MULTIPLE + hoursWorked * wages;
          }
          else
          {
            salary = hoursWorked * wages;
          }
          // Return the salary
           return salary ;

         } // end of calculateSalary method
} // End of Lab10 class

使用此输入文件时：

3
Smith 12.50 25
Jones 25.89 60
Brown 7.86 19.89

我得到了我想要的输出，但是这个消息在最后得到了解释：

Exception in thread "main" java.util.NoSuchElementException
    at java.util.Scanner.throwFor(Scanner.java:855)
    at java.util.Scanner.next(Scanner.java:1364)
    at Lab10.main(Lab10.java:32)

有人可以告诉我这意味着什么以及如何解决它？

Answer 1

你循环太多次了。

你有3名员工，因此应该像这样循环：

for ( ; i < EmployeeNumber; i ++ )
{
    name = scan.next () ;
    ...
 }

Answer 2

Java的数组索引从0开始，所以如果你有3个元素，那么它们存储在0,1和2中。如上所述，在你的for循环中，如果你只是把i＆lt; EmplyeeNumber足够，而不是EmployeeNumber + 1。

是什么导致此错误消息？

2 个答案: