为什么我的 Java Zork 克隆无法正确循环？

Question

我正在制作 Zork 克隆，每当它循环时，Eclipse 中就会出现错误：

import java.util.Scanner;
public class Level1 {
public static void main(String[] args) {
    int x;  
    for(x=1; x<10; x++) {
        System.out.println ("Welcome to Sork - by Wyatt Lucas");
        System.out.println (" ");
        System.out.println ("Do you want to play?");
        Scanner first = new Scanner(System.in);
        @SuppressWarnings("unused")
        String firstInput;
        firstInput = first.nextLine();
        System.out.println("Well, it doesn't matter!");
        System.out.println("Use commands such as LOOK and GO NORTH \nto complete your adventure.");     
        System.out.println("");
        System.out.println("You are in a room.");
        Scanner second = new Scanner(System.in);
        String secondInput = second.nextLine();
        String look = "look";
        if(secondInput.equalsIgnoreCase(look)) {
            System.out.println("You look around and see a DOOR \nand a KEY on the floor.");
        }
        else {
            //don't use System.err.println. Just use System.out.println
            System.out.println("I do not understand that.");
            continue;
        }
        Scanner third = new Scanner(System.in);
        String thirdInput = third.nextLine();
        String pick_up_key = "pick up key";
        if(thirdInput.equalsIgnoreCase(pick_up_key)) {
            System.out.println("You picked up the KEY.");
        } else {
            System.out.println("I do not understand that.");
            continue;
        }
        Scanner fourth = new Scanner(System.in);
        String fourthInput = fourth.nextLine();
        String open_door = "open door";
        if(fourthInput.equalsIgnoreCase(open_door)) {
            System.out.println ("You open the door and are immediately \neaten by a grue!");
        } else {
            System.out.println("I do not understand that.");
        }

        first.close();
        second.close();
        third.close();
        fourth.close();
        try {
            Thread.sleep(1997);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}
}

Answer 1

运行代码到打开门的位置会

Exception in thread "main" java.util.NoSuchElementException: No line found
at java.util.Scanner.nextLine(Scanner.java:1516)
at Level1.main(Level1.java:12)

出现这种情况，因为您在最后调用了所有 third.close() 来关闭 System.in。只制作一台扫描仪，并且永远不要关闭它。