Java Program To Reverse a String

Here's a simple Java program to reverse a string:

public class ReverseString {
    public static void main(String[] args) {
        // Input string
        String str = "Hello, World!";

        // Call the reverseString method and print the result
        System.out.println("Original string: " + str);
        System.out.println("Reversed string: " + reverseString(str));
    }

    // Method to reverse a string
    public static String reverseString(String str) {
        // Convert the string to a character array
        char[] charArray = str.toCharArray();

        // Initialize variables for indices
        int left = 0;
        int right = charArray.length - 1;

        // Iterate through the character array and swap characters
        while (left < right) {
            // Swap characters at left and right indices
            char temp = charArray[left];
            charArray[left] = charArray[right];
            charArray[right] = temp;

            // Move indices towards the center
            left++;
            right--;
        }

        // Convert the character array back to a string
        return new String(charArray);
    }
}

This program defines a reverseString method that takes a string as input, converts it to a character array, and then iterates through the array to swap characters from both ends until the entire string is reversed. Finally, it returns the reversed string. The main method demonstrates how to use this method by passing a sample string and printing the original and reversed strings.