Using Scanner.next() to get text input

java, java.util.scanner

Solution

The reason for the exception is that you are calling `keyIn.close()` after you use the scanner once, which not only closes the `Scanner` but also `System.in`. The very next iteration you create a new `Scanner` which promptly blows up because `System.in` is now closed. To fix that, what you should do is only create a scanner once before you enter the `while` loop, and skip the `close()` call entirely since you don't want to close `System.in`.

After fixing that the program still won't work because of the `==` and `!=` string comparisons you do. When comparing strings in Java you must use `equals()` to compare the string contents. When you use `==` and `!=` you are comparing the object references, so these comparisons will always return false in your code. Always use `equals()` to compare strings.

while (!quit){
    Scanner keyIn = new Scanner(System.in);
    String c = "x";
    while (!c.equals("y") && !c.equals("n")) {
        c = keyIn.next();
    }
    if (c.equals("n"))
        quit = true;
}

Problem

I am trying to get text input from the keyboard in Java 6. I am new to the language and whenever i run the following code, I get this error: ``` package test1; import java.util.Scanner; public class Test { public static void main(String[] args) { boolean quit = false; while (!quit){ Scanner keyIn; String c = "x"; while (c != "y" && c != "n") { keyIn = new Scanner(System.in); c = keyIn.next(); keyIn.close(); } if (c == "n") quit = true; } } } Exception in thread "main" java.util.NoSuchElementException at java.util.Scanner.throwFor(Scanner.java:838) at java.util.Scanner.next(Scanner.java:1347) at test1.Test.main(Test.java:11) ``` Am I mis-using the next() method? I thought it would wait for user input but it looks like it isn't and throwing the exception saying that there is nothing left in the scanner.

Original source