为什么我的扫描仪在我的用户提示后不接受任何输入？[重复]

Question

我正在编写一个程序，帮助火星定居者计算他们潜在房屋的面积/大小。程序的整个前半部分按预期工作，但由于某种原因，当我提示用户是否愿意输入第二所房子时，我的扫描仪不再接受任何输入，程序执行结束，不允许我键入yes或no作为响应，它只是打印出用户提示并中断。我到底做错了什么？

import java.util.Scanner;

public class MartianHouses{
    public static void main(String[] args){
    /*Set up scanner & declare variables*/
    Scanner sc = new Scanner(System.in);
    double sqFt = 14.5;

    /*Receive input from user*/
    System.out.println("Enter the settler's name: ");
    String name = sc.nextLine();
    System.out.println("Enter the length of a side of the house: ");
    double s = sc.nextDouble();

    /*Calculate area of floor&roof*/
    double floorArea = 2*s*s*(1 + Math.sqrt(2));

    /*Calculate walls area*/
    double wallsArea = 8 * 12 * s;

    /*Calculate total area*/
    double totArea = (floorArea * 2) + wallsArea;

    /*Calculate floor cost*/
    double totCost = totArea * sqFt;

    /*Print results*/
    System.out.print(name + " has a house surface area of ");
    System.out.printf("%,.2f", totArea);
    System.out.print(" and a cost of $");
    System.out.printf("%,.2f", totCost);
    System.out.print(".");

    System.out.println(" Would you like to enter another house? Enter no to exit.");
    String response = sc.nextLine();
    double sqFt2 = 14.5;

    switch(response.toLowerCase()) {
        case "yes" : 
        System.out.println("Enter the settler's name: ");
        String name2 = sc.nextLine();
        System.out.println("Enter the length of a side of the house: ");
        double s2 = sc.nextDouble();

        double floorArea2 = 2*s2*s2*(1 + Math.sqrt(2));

        double wallsArea2 = 8 * 12 * s2;

        double totArea2 = (floorArea2 * 2) + wallsArea2;

        double totCost2 = totArea2 * sqFt2;

        System.out.print(name2 + " has a house surface area of ");
        System.out.printf("%,.2f", totArea2);
        System.out.print(" and a cost of $");
        System.out.printf("%,.2f", totCost2);
        System.out.print(".");
        break;

        case "no" : 
        break;
    }
        }
    }

Answer 1

执行sc.nextDouble（）时，键入一个输入，后跟一个换行符（enter按钮）。

因此，双精度 s 获取您输入的值，但在扫描仪缓冲区中，您仍然有一个换行符。

你能做到的

>

在 sc.next 双 （） 之后，执行一个 sc.next（） / sc.nextLine（） 以清除缓冲区。

另一种选择是

字符串s=sc.nextDouble（）；

然后尝试将s转换为整数。