Java program stops running after asking for user input

Question

My code compiles but once I run it, it asks for user input and then stops. However, the program says it's still running but it doesn't move on to execute the rest of the code and I can't figure out why.

Here's a portion of my code. It stops after I ask the user how many questions they would like to answer. According to my debugger, it specifically stops at "qNum = console.nextInt();" when I enter in a valid input.

import java.util.*;
import java.io.*;

public class QuizBowlRedo implements Quiz {  
    private Player player;     // player object
    private String file;       // name of file
    private int qNum;          // number of questions player wants to answer
    private int qNumFile;      // number of questions in file
    private ArrayList<Question> questionsArr; // holds Question objects
    private boolean questionsAsked[];



// Constructor
public QuizBowlRedo(String fName, String lName, String file) throws FileNotFoundException {
    player = new Player(fName, lName);
    Scanner gameFile = new Scanner(new File(file));
    qNum = numOfQuestionsToPlay();
    qNumFile = maxNumQFile(gameFile);
    questionsArr = new ArrayList<Question>();
    readFile();
    questionsAsked = new boolean[qNumFile];    
}

// asks user how many questions to ask
public int numOfQuestionsToPlay() {
    Scanner console = new Scanner(System.in); 

    // CHECKS FOR VALID USER INPUT
    boolean check = false;
    do {
        try {
            System.out.print("How many questions would you like (out of 3)? ");
            if(console.nextInt() > 3) {
                System.out.println("Sorry, that is too many.");
                check = false;
             }               
            else {
                check = true;
                qNum = console.nextInt();           
            }

        }
        catch(InputMismatchException e) {
           System.out.println("Invalid input. Please try again.");
           console.nextLine(); 
           check = false;  
        }
   }
   while(check == false);
   return qNum; 
}

Dawood ibn Kareem · Accepted Answer · 2016-03-13 04:35:59Z

1

You're calling nextInt() at two different places in your program, so if your program goes into the "else" block, then it will wait for the result a second time.

You should call nextInt() only once, and assign the result to a local variable before continuing. You could do it like this.

        System.out.print("How many questions would you like (out of 3)? ");
        int answer = console.nextInt();
        if(answer > 3) {
            System.out.println("Sorry, that is too many.");
            check = false;
         }               
        else {
            check = true;
            qNum = answer;           
        }

answered Mar 13, 2016 at 4:35

Dawood ibn Kareem

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Comments

MikeCAT · Accepted Answer · 2016-03-13 04:36:33Z

0

console.nextInt() reads an integer, so you mustn't call it unless you want to read an integer.

Try this:

System.out.print("How many questions would you like (out of 3)? ");
if((qNum = console.nextInt()) > 3) {
    System.out.println("Sorry, that is too many.");
    check = false;
 }               
else {
    check = true;        
}

answered Mar 13, 2016 at 4:36

MikeCAT

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