Write a java program that reverses the given string sentence.

In this tutorial you will learn to reverse the given string sentence using for loop and while loop in java programming.

For example 
Input : My name is Rutu Shah
Output : Shah Rutu is name My.

Using while Loop.

Lets begin with reversing string first using while Loop.

/*
* Prepared by : Rutu Shah
* This program reverse the entire string using while loop
* */
import java.util.Scanner;

public class ReverseWords {
    public static void main(String[] args) {
        {
            System.out.print("Please enter the String :");
            Scanner scan = new Scanner(System.in);
            String ipString = scan.nextLine();
            char[] ch = ipString.toCharArray();

            String result = "";

            int i = ch.length - 1;
            while (i >= 0) {
                int k = i;
                while (i >= 0 && ch[i] != ' ') {
                    i--;
                }
                int j = i + 1;
                while (j <= k) {
                    result = result + ch[j];
                    j++;

                }
                result = result + " ";
                i--;
            }
            System.out.println("Reversed String : " + result);
        }
    }
}

Output

Using For Loop

/*
 *  Prepared by : Rutu Shah
 *  This program reverse the entire string using for loop
 * */
import java.util.Scanner;

public class ReverseStringUsingForLoop {
    public static void main(String[] args) {
        String input,stringReverse = "", stringReverse1 = "";
        int size = 0, newIndex = 0;

        //Program's logic
        Scanner scanner = new Scanner(System.in);
        System.out.print("Please enter the String : ");
        input = scanner.nextLine();

        for (size = 0; size < input.length(); size++){
            newIndex = input.indexOf(' ', size);
            if (newIndex != -1){
                stringReverse1 = input.substring(size, newIndex);
                stringReverse1 = " " + stringReverse1;
                size = newIndex;
            }else {
                stringReverse1 = input.substring(size);
                size = size+ stringReverse1.length();
            }
            stringReverse = stringReverse1 + stringReverse;
        }
        System.out.println("Reversed String : " +stringReverse);
    }
}

Output