string tukar

import java.util.Scanner;
public class Tugas3{
public static void Tukar(String text){
    StringBuffer output = new StringBuffer(text);
    int[] c1 = new int[32]; int[] c2 = new int[32];
    char[] replacec1 = new char[32]; char[] replacec2 = new char[32];
    int i,x=0,y=0;
    char c;
    int d=text.length()-1;
    char a=text.charAt(0);
    char b=text.charAt(d);
    for(i=0;i<text.length();i++){
        c=text.charAt(i);
        if(c==Character.toUpperCase(a)||c==Character.toLowerCase(a)){
            c1[x]=i;
            if(Character.isUpperCase(c))
                replacec1[x]=Character.toUpperCase(b);
            else
                replacec1[x]=Character.toLowerCase(b);
            x++;
        }
        else if(c==Character.toUpperCase(b)||c==Character.toLowerCase(b)){
            c2[y]=i;
            if(Character.isUpperCase(c))
                replacec2[y]=Character.toUpperCase(a);
            else
                replacec2[y]=Character.toLowerCase(a);
            y++;
        }
    }
    for(i=0;i<x;i++){
        output.setCharAt(c1[i],replacec1[i]);
    }
    for(i=0;i<y;i++){
        output.setCharAt(c2[i],replacec2[i]);
    }
    System.out.println("Hasil : "+output.toString());
}
public static void main(String args[]){
    Scanner input = new Scanner(System.in);
    System.out.print("Masukkan kalimat : ");
    Tukar(input.nextLine());
  }
}