public class CharacterCount { public static void main(String[] args) { String str = "Hello, world!"; int count = 0; // Iterate through each character until null character is encountered for (int i = 0; str.charAt(i) != '\0'; i++) { count++; System.out.println("Character at position " + i + ": " + str.charAt(i)); } System.out.println("Number of characters: " + count); } }