Having a NoSuchElementException and I couldn't find how to fix that

Question

I have written some code for a word guessing game. It reads a character from user input and searches that character in a word; depending on whether the character is in the word or not, the program returns and controls some variables.

Here's the code:

import java.util.Random;
import java.util.Scanner;
import java.lang.Character;

public class Game {

    private String word;
    private int wordNum;
    private char[] wordinArr = new char[30];
    private char[] wordinDashes = new char[30];
    private int lettersFound = 0;
    int numOfGuesses=10;

    public Game() {

        Random random = new Random();   //επιλογή τυχαίας λέξης
        wordNum = random.nextInt(120);
        //System.out.println("Random Number: "+wordNum);
        word = Lexicon.getWord(wordNum);
        //System.out.println(word); 
    } 

    public void startTheGame() {

        do {


            wordinArr = word.toCharArray();
            System.out.println(wordinArr);
            System.out.println(word.length());
            for(int i=0;i<word.length();i++) 
                wordinDashes[i]='-';
            System.out.println("The random word is now: ");
            System.out.println(wordinDashes);
            System.out.println("You have  "+numOfGuesses+" guesses left.");

            if(MakeATry())
                numOfGuesses-=1;
        }while(numOfGuesses !=0 && lettersFound!=word.length());

        if(lettersFound==word.length())
            System.out.println("Congratulations! You guessed the word: "+word);
        else {
            System.out.println("Unfortunately you didn't find the word. The word was"+word);
            System.out.println("Try again to find the next word!");
        }
    }


    public boolean MakeATry() {

        Scanner input = new Scanner(System.in);
        System.out.println("Your guess: ");
        char guess = input.next().charAt(0);

        if(Character.isLowerCase(guess)){            
            char temp = Character.toUpperCase(guess);
            guess = temp;
        }

        for(int i=0;i<word.length();i++) { 
            if(guess==wordinArr[i]) {
                System.out.println("The guess is CORRECT!");
                wordinDashes[i]=guess;
                input.close();
                lettersFound++;
                return true;
            }
        }           
        input.close();
        return false;       
    }

}

But when I run it, I always get this error:

Exception in thread "main" java.util.NoSuchElementException  
    at java.util.Scanner.throwFor(Unknown Source)  
    at java.util.Scanner.next(Unknown Source)  
    at Game.MakeATry(Game.java:54)  
    at Game.startTheGame(Game.java:37)  
    at Main.main(Main.java:17)

The line 54 in MakeATry() method is that line ->char guess = input.next().charAt(0);. I have spent hours trying to figure out how to fix it, but no result. Does anyone has any idea about this error?

Thank you in advance.

could you please also paste your maln method as well or entire class would be good — Pradeep, Oct 24 '17 at 14:36
Ok, I pasted the entire class which includes the method I have the problem with. — Vaggos B, Oct 24 '17 at 14:41
You need to call Scanner.nextLine() , i.e. in this case input .nextLine(). You aren't advancing to the next line, so you run out of tokens on this line — Pradeep, Oct 24 '17 at 14:41
@Neo The user must type a chatacter, a letter to be accurate. — Vaggos B, Oct 24 '17 at 14:50
As a user, I type a letter and after that the program stops and I have that error — Vaggos B, Oct 24 '17 at 14:54
@Pradeep Where i should call input.nextLine() in order not to have error, because i tried adding it but again the error hasn't been fixed. — Vaggos B, Oct 24 '17 at 15:18
https://stackoverflow.com/questions/13729294/nosuchelementexception-with-java-util-scanner can you please have a look at this link — Pradeep, Oct 24 '17 at 15:58
Yeah of course I will! I am new to all this and I have a lot to learn. Thanks for the help! — Vaggos B, Oct 24 '17 at 16:07

score 1 · Accepted Answer · answered Oct 24 '17 at 15:20

1

instead of

input.close();

use

input.reset();

answered Oct 24 '17 at 15:20

user3631935

61
6

Thanks! I used input.reset(); and I dont have that error anymore. – Vaggos B Oct 24 '17 at 15:43

score 0 · Answer 2 · answered Oct 24 '17 at 14:41

Firstly, your program should verify that the user has in fact entered some input. This sounds like the scanner has reached the end of the input (which is, in this case, nothing) and throws an exception because you still want more, as it should.

As stated in this SO answer, some IDEs do not allow user input, so even if you are entering input, it may not register in your program. Try another IDE or even compiling the whole thing by hand.

Having a NoSuchElementException and I couldn't find how to fix that

2 Answers2