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java - Scanner keeps skipping input whist using nextInt() and loops

I am using a while loop to make sure that the value entered to a scanner object is an integer as such:

while (!capacityCheck) {
        try {
            System.out.println("Capacity");
            capacity = scan.nextInt();
            capacityCheck = true;
        } catch (InputMismatchException e) {
            System.out.println("Capacity must be an integer");
        }
    }

however, if the user does not enter an integer, when it should go back and take another input it just repeatedly prints "Capacity" followed by the output in the catch without asking for more input. How do I stop this?

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1 Answer

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scan.nextLine();

Put this piece of code inside your catch block, to consume the non integer character along with the new line character which is stays in the buffer(hence, infinitely printing the catch sysout), in the case where you've given a wrong input.

Ofcourse, there are other cleaner ways to achieve what you want, but I guess that will require some refactoring in your code.


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