循环不执行多次

Question

我应该制作一个程序,不断接受桌面订单数据,并显示超过36英寸长,至少有一个抽屉的橡木书桌的所有相关信息.

import java.util.*;

public class MangMaxB 
{
    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);
        char ans;
        int orderNum=0, length=0, width=0, numDrawer=0, price=1000;
        String name;

        System.out.print("Do you wish to enter Oak " +
                        "desk order data? (y/n)");
        ans = input.nextLine().charAt(0);

        while (ans != 'n')
        {  
            System.out.print("Enter customer name: ");
            name=input.nextLine();

            System.out.print("Enter order number: ");
            orderNum=input.nextInt();    

            System.out.print("Enter length and width of Oak desk" +
                        " separated by a space: ");
            length = input.nextInt();
            width = input.nextInt();

            System.out.print("Enter number of drawer/s: ");
            numDrawer=input.nextInt();

            if ((length>36)&&(numDrawer>=1))
            {
                if ((length*width)>750)
                {
                    price+= 250;
                }

                price+= (numDrawer*100);
                price+= 300;

                System.out.println("\nOak desk order information:\n" 
                        + "Order number: " + orderNum + "\n"
                        + "Customer name: " + name + "\n"
                        + "Length: " + length + ", width: "
                        + width + ", surface: " + (length*width)
                        + "\n" + "Number of drawer/s: " + numDrawer
                        + "\nPrice of the desk is P " + price);
            }

            else
            {
                System.out.println("\nOak desk order isn't over 36 " +
                        "inches long and doesn't have a drawer");
            }

            System.out.print("Any more items? (y/n) ");
            ans = input.nextLine().charAt(0);
        }
    }
}

我能够输入数据并显示它,但在第二次尝试,因为它是一个循环,它不起作用.

它说:"在异常线程'主要’java.lang.StringIndexOutOfBoundsException:字符串索引超出范围:在java.lang.String.charAt(来源不明)在controlStruc.MangMaxB.main 0"

我该如何解决？

Answer 1

nextInt()不读取行的结尾 - 只是下一个整数.你需要调用nextLine()后nextInt(),如果你想阅读该行的其余部分.

目前,你没有这样做,所以最后一个nextLine()方法只读取整数后的空行的其余部分,并立即返回一个空字符串,导致异常.

在这种情况下,在nextLine()这里拨打电话应该可以解决问题:

System.out.print("Enter number of drawer/s: ");
numDrawer=input.nextInt();
input.nextLine(); //Added nextLine() call