ReverseStringExample.java

package com.codinginterview;

public class ReverseStringExample {

 public static void main(String[] args) {
 System.out.println("**** Reverse a String Example *****");
 String str = "Dharmendra";
 System.out.println("Original String ::"+ str);
 System.out.println("Reverse String - 1 ::"+reverseString1(str));
 System.out.println("Reverse String - 2 ::"+reverseString2(str));
 System.out.println("Reverse String - 3 ::"+reverseString3(str));
 }

 private static String reverseString1(String str){

 if(str != null || str.isBlank() || str.isEmpty()){
 StringBuffer sb = new StringBuffer(str);
 return sb.reverse().toString();
 }
 return null;
 }
 private static String reverseString2(String str){

 String rev = "";
 int len = str.length();
 for(int i = len -1; i>= 0; i--){
 rev = rev + str.charAt(i);
 }
 return rev;
 }

 private static String reverseString3(String str){

 String rev = "";
 char a[] = str.toCharArray();
 int len = a.length;
 for(int i = len -1; i>= 0; i--){
 rev = rev + a[i];
 }
 return rev;
 }
}