Careeroza

Conditions and Loops

if, else and for

Conditions decide pass or fail. Loops repeat an action, for example checking every product on a search page.

Example

Check that every product price is within the selected filter (500 to 2000):

public class Main {
    public static void main(String[] args) {
        int[] prices = {799, 1299, 1999, 2499, 650};
        int min = 500, max = 2000;
        int failures = 0;

        for (int i = 0; i < prices.length; i++) {
            if (prices[i] >= min && prices[i] <= max) {
                System.out.println("Product " + (i + 1) + ": " + prices[i] + " OK");
            } else {
                System.out.println("Product " + (i + 1) + ": " + prices[i] + " OUTSIDE FILTER");
                failures++;
            }
        }
        System.out.println(failures == 0 ? "PASS" : "FAIL (" + failures + " wrong)");
    }
}

Output

Product 1: 799 OK
Product 2: 1299 OK
Product 3: 1999 OK
Product 4: 2499 OUTSIDE FILTER
Product 5: 650 OK
FAIL (1 wrong)

while for Retrying

Example

A while loop is handy for "try again up to 3 times":

public class Main {
    public static void main(String[] args) {
        boolean[] attempts = {false, false, true};   // pretend the 3rd try succeeds
        int tries = 0;
        boolean ok = false;
        while (!ok && tries < 3) {
            ok = attempts[tries];
            tries++;
            System.out.println("Attempt " + tries + ": " + (ok ? "success" : "failed"));
        }
        System.out.println("Result after " + tries + " tries: " + ok);
    }
}

Output

Attempt 1: failed
Attempt 2: failed
Attempt 3: success
Result after 3 tries: true