program reverse a string in java code example

Example 1: reverse string java

// Use StringBuilder for non-thread environment, it is faster
String string="whatever";
String reverse = new StringBuilder(string).reverse().toString();
System.out.println(reverse);

Example 2: Reverse a string in java without using reverse function

// Reverse a string in java without using reverse function
import java.util.Scanner;
public class ReverseWithoutFunction 
{
   public static void main(String[] args) 
   {
      Scanner sc = new Scanner(System.in);
      System.out.println("Please enter a string: ");
      String strInput = sc.nextLine();
      int len = strInput.length();
      String strReverse = "";
      System.out.println("Reverse a string without using reverse function: ");
      for(int a = len - 1; a >= 0; a--)
      {
         strReverse = strReverse + strInput.charAt(a);
      }
      System.out.println(strReverse);
      sc.close();
   }
}