Example: Reverse String using Recursion in Java

// Reverse String using Recursion
public class Main {

    // Recursive method to reverse a string
    public static String reverseStringRecursive(String str) {
        // Step 1: Base case: if the string is null, empty, or has one character, return it
        if (str == null || str.isEmpty() || str.length() == 1) {
            return str;
        }
        // Step 2: Recursive step: take the last character and prepend it to the
        // reversed string of the substring excluding the last character.
        // Or, take the first character and append it after the reversed rest of the string.
        // We'll use the latter for simpler implementation.
        return reverseStringRecursive(str.substring(1)) + str.charAt(0);
    }

    public static void main(String[] args) {
        // Step 1: Define the original string
        String originalString = "hello";

        // Step 2: Call the recursive method to reverse the string
        String reversedString = reverseStringRecursive(originalString);

        // Step 3: Print the original and reversed strings
        System.out.println("Original String: " + originalString);
        System.out.println("Reversed String: " + reversedString);
    }
}