Palindrom | Stack Java

package lat01b;
import java.util.Scanner;
import java.util.Stack;

public class Palindrom {
    public static void main(String[ ] args){
        Scanner input = new Scanner(System.in);
        System.out.print("Masukkan kalimat : ");
        String kal = input.nextLine( );
        System.out.println(" Hasil = " + reverseString(kal));
        if(reverseString(kal).equalsIgnoreCase(kal)) System.out.println(" Palindrom");
        else System.out.println(" Bukan Palindrom");
    }
    public static String reverseString(String input) {
        Stack<Character> st = new Stack<>();
        StringBuilder sb = new StringBuilder();
        for(int i = 0; i < input.length(); ++i) st.push(input.charAt(i));
        while(!st.empty()) {
            char c = st.pop();
            sb.append(c);
        }
        return sb.toString();
    }
}

/**
 * @author yufieko
 */