Question

i want to know if there is something missing.
if i will input “race car” it must show Palindrome and if i will input “string beans” it must show not a palindrome but when i run the code it has an error.

Exception in thread “main” java.lang.StringIndexOutOfBoundsException: String index out of range: 3
at java.lang.String.charAt(String.java:686)
at praktis.Palindrome.main(Palindrome.java:11)

     public static void main (String args[]) {
        String word = JOptionPane.showInputDialog("Enter a String:");
        String finalword = word.replaceAll(" ","").toLowerCase();

        for (int x = word.length(); x >= word.length()-1; x--) {
        //this is my line 11 // 
                 finalword.charAt(x);
       }
            if(word.equals(finalword)) {
                JOptionPane.showMessageDialog(null, "Palindrome");
            }
            else {
                JOptionPane.showMessageDialog(null, "Not a Palindrome");
            }
    }

Answer 1

for (x = word.length()-1; x >= 0; x--)

EDIT:

String word = JOptionPane.showInputDialog("Enter a String:");
        String finalword = "";
        int x;
        for (x = word.length()-1; x >= 0; x--) {
            finalword = finalword + word.charAt(x);
        }
        if (word.equals(finalword)) {
            JOptionPane.showMessageDialog(null, "Palindrome");
        } else {
            JOptionPane.showMessageDialog(null, "Not a Palindrome");
    }