Reverse String

import java.util.Scanner;

public class executavel
{

    public static void inverteFraseNaMao(String a)
    {
        char frase[] = a.toCharArray();

        System.out.println("\nInvertendo na mão...");
        int i, j = frase.length - 1;
        char aux;
        for(i = 0; i <= j; i++, j--)
        {
            aux = frase[i];
            frase[i] = frase[j];
            frase[j] = aux;
        }
        System.out.println(frase);
    }

    public static void inverteFraseComBuilder(String a)
    {
        StringBuilder frase = new StringBuilder(a);
        System.out.println("\nInvertendo no mole(StringBuilder)...");
        frase.reverse();
        System.out.println(frase);
    }

    public static void main(String[] args)
    {
        System.out.println("Digite uma string qualquer: ");
        Scanner scanner = new Scanner( System.in );
        String a = scanner.nextLine();

        inverteFraseNaMao(a);
        inverteFraseComBuilder(a);
    }
}