I don't know what is wrong with my program

I want to print [str1+" is palindrome"] for 1331 only once

and [str1+ " is not palindrome"]for 1234 only once

17 User enter a string System. out.print("Enter a string:"); String str1-keyboard.nextLine); 18 19 20 21 //User enter a string until the string is empty while(!str1.equals("")) 23 24 25 26 27 28 29 30 31 32 //Assume the string is palindrome boolean isPalindrome true; //set an index to position0 int index -0; while(index