using static boolean method

Question

My code:

import java.util.Scanner;

public class MonthMapper{
    static String month;
    static int month_num;

    public static boolean isMonthNumber (String str) { 
        month = str;
        month_num = Integer.parseInt(month);
        return (month_num >= 0 && month_num < 12); 
    } 

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter Month: ");
        month = sc.next();
        System.out.println (isMonthNumber (Integer.toString(month_num)));
    }
}

I have to write a static class method boolean isMonthNumber(String str) that takes a String as an input and returns boolean value. The method returns True if the input string represents an integer value between 1 and 12, otherwise the method returns should return False.

Currently for some reason my program always returns true even when i enter a value greater than 12.

What is the value of `month_num` when you invoke `Integer.toString(month_num)`? How do you figure? — Sotirios Delimanolis, Sep 18 '15 at 18:02
you're right it does, but when i enter a number larger than 12, it also returns true — Win, Sep 18 '15 at 18:03
@ Sotirios Delimanolis It's supposed to convert the integer from user input back into a string so it can be printed, so it can be any integer that the user has inputted — Win, Sep 18 '15 at 18:06
What is the current specific value of `month_num` when you invoke `Integer.toString(month_num)`? — Sotirios Delimanolis, Sep 18 '15 at 18:08

MaxZoom · Accepted Answer · 2015-09-18T18:11:15.227

2

You pass mounth_num variable to a method, but the month variable has the read value.

Replace with this:

public static void main(String[] args){
  Scanner sc = new Scanner(System.in);
  System.out.print("Enter Month: ");
  System.out.println(isMonthNumber (sc.next()));
}

edited Sep 18 '15 at 18:11

answered Sep 18 '15 at 18:04

MaxZoom

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I see, but now I have to enter the input twice for the program to work, how can i make it so i only have to input once? Edit: nevermind I realized how silly a question this was. Thank you very much for your swift answer! :-) – Win Sep 18 '15 at 18:08

using static boolean method

1 Answers1