Help with this code - java help on CodeGym

Can someone help with this and constructively criticize.. I have also included the program I wrote which is very basic but I'm trying to solidify my knowledge on if else statements and loops. I want to write a program that: - takes the user's input - Both integers must be greater than 0. - accepts two integers and then calculates the sum of the two - Displays the sum on the screen. - If any of these conditions are not met, an error message is displayed. - Also the user gets 10 chances to enter the integers before the program breaks/stops. - On the 9th try, the program lets the user know (with a different but appropriate error message) that this is the last try

import java.util.Scanner;

public class UserInput {
    public static void main(String[] args) {
        int sumArray[] = {1,2,3,4,5,6,7,8,9,10};
        for (int i=0; i<sumArray.length; i++) {

      Scanner sum = new Scanner(System.in);
        System.out.println("Enter more than one number to calculate the sum. Number must be > 0. ");
        int a = sum.nextInt();
        int b = sum.nextInt();
        int combo = a+b;
        System.out.println(combo);


            if (combo == a || combo < a || combo == b || combo < b) {
                System.out.println("Error - Try again! You must enter" +
                        " more than two numbers AND each number entered must be > 0");
                }
            else {
                System.out.println("Thank you!");
                break;
            }
            }

        }

    }

public class Main { private static final int TRIES = 5; public static void main(String[] args) { Util util = new Util(); try { int num1 = util.getIntWithMaxTries("Enter first number (>0)", "This is your last try!", TRIES); int num2 = util.getIntWithMaxTries("Enter second number (>0)", "This is your last try!", TRIES); System.out.format("%d + %d = %d", num1, num2, num1 + num2); } catch (MaxTriesReachedException e) { System.out.println("you did not enter a valid integer in " + TRIES + " times"); } } }

import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class Util { private static final BufferedReader console = new BufferedReader(new InputStreamReader(System.in)); public String readString() throws IOException { return console.readLine(); } public int readInt() throws IOException, NumberFormatException { return Integer.parseInt(readString()); } public int validateGreaterThan(int number, int other) throws NumberFormatException { if (number > other) return number; throw new NumberFormatException(); } /** * @param message the message to display * @param lastTryMessage the message to display if it is the last try * @param tries the maximum number of tries before aborting with a MaxTriesReachedException * @return the user input * @throws MaxTriesReachedException */ public int getIntWithMaxTries(String message, String lastTryMessage, int tries) throws MaxTriesReachedException { while (tries-- > 0) { try { System.out.format("%s%s: ", tries == 0 ? lastTryMessage + " " : "", message); return validateGreaterThan(readInt(), 0); } catch (IOException | NumberFormatException ignore) { } } throw new MaxTriesReachedException(); } }

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Thomas

Level 41 , Bayreuth, Germany

18 March, 15:29

Usually you put repetitive code into separate methods, classes. Then you write a method that calls that repetitve code (including all your requirements). To determine if all is correct you could either make use of Exceptions, Optionals or wrapper classes. I'll show you an example using exceptions as user input usually needs exception handling (or messing around with scanner and validating its return values - don't get me wrong, Scanner is very useful in a lot of cases). Wrapper class may be easier though. I did not fullfill your requirement of 10 tries for both numbers together but changed to 5 tries per input. You can change that if you use a static counter variable inside the Util class. If you intende to run several input rounds, then you should add some way to reset that static counter variable. You should put the classes into the same package. Exception to show that the max inputs have been reached

public class MaxTriesReachedException extends Exception {
}

Main class for testing

18 March, 15:30

The class handling the input

There are a lot more and better possibilities. You'll see what I mean once you're looking into frameworks like Spring or Jakarta and their input validation.

Java coffee QA Automation Engineer

18 March, 23:17

Wow, thank you so much for your very detailed response. I really appreciate it and look forward to the more advanced topics and framework. Hopefully very soon I'll be able to write more sophisticated code like yours.