Example: Manual Char Array Comparison in Java

// Manual Char Array Comparison
public class Main {
    /**
     * Manually compares two character arrays for content equality.
     * Handles null arrays and arrays of different lengths.
     */
    public static boolean areCharArraysEqualManual(char[] arr1, char[] arr2) {
        // Step 1: Handle reference equality (same array object)
        if (arr1 == arr2) {
            return true;
        }

        // Step 2: Handle null arrays or arrays with different lengths
        if (arr1 == null || arr2 == null || arr1.length != arr2.length) {
            return false;
        }

        // Step 3: Iterate through elements and compare them
        for (int i = 0; i < arr1.length; i++) {
            if (arr1[i] != arr2[i]) {
                return false; // Found a differing character
            }
        }

        // Step 4: All characters are equal, arrays are content-equal
        return true;
    }

    public static void main(String[] args) {
        char[] passwordA = {'p', 'a', 's', 's', 'w', 'o', 'r', 'd'};
        char[] passwordB = {'p', 'a', 's', 's', 'w', 'o', 'r', 'd'};
        char[] passwordC = {'p', 'a', 's', 's', 'w', 'o', 'r', 'd', '1'};
        char[] passwordD = {'P', 'a', 's', 's', 'w', 'o', 'r', 'd'}; // Different case

        System.out.println("passwordA vs passwordB: " + areCharArraysEqualManual(passwordA, passwordB));
        System.out.println("passwordA vs passwordC: " + areCharArraysEqualManual(passwordA, passwordC));
        System.out.println("passwordA vs passwordD: " + areCharArraysEqualManual(passwordA, passwordD));
        System.out.println("passwordA vs null: " + areCharArraysEqualManual(passwordA, null));
        System.out.println("null vs null: " + areCharArraysEqualManual(null, null)); // Should be true if both null
    }
}