Day: February 16, 2019

Hi guys so I was playing with some code which would determine the whether a string is a palindrome or not. Its been a mixed bag of results with some palindromes being detected while others aren't. I do apologize to the lack of polish of my comments but I hope that someone might be able to see where the error is and give me good feedback. I think the error is in the set of code that removes the special characters from the string.
As a reference, I am using this webiste: http://www.palindromelist.net/ as the source for the palindrome strings. However the really long ones have resulted in errors.

package palindrome;
/* 
 * Author: venom 
 * Last Edit Date: 2/15/2019
 * This program will check whether a string is a palindrome
 * JDK 11
 */

import java.util.Scanner; // Scanner class used to collect user input of various strings
import javax.swing.JOptionPane; // Will be used to build the GUI for the palindrome test

public class Palindrome {

    public static void main(String[] args) {
        palindrome();
    }

public static void palindrome(){
        //Create the a scanner object to collect user input However will be re-enabled at the end
        Scanner sc = new Scanner(System.in);

        //System.out.print();
        //Variable to store the user string
        String input = null;
        do {
       input = JOptionPane.showInputDialog(null,"Welcome to the Palindrome Test App.\n" + 
                                                    "Enter a string to test: ", "Palindrome App", 
                                                    JOptionPane.INFORMATION_MESSAGE);
        } while (input.isEmpty() == true);

        input = input.toLowerCase();// set the input to lower case 
        // Here we are removing all special characters from a string
        input = input.replace(" ","").replace("!", "").replace(".", "").replace(",", "").replace("?","")
                .replace("-", "").replace("/", "").replace("\\","").replace("'", "").replace("\"", "").replace(":", "")
                .replace("`", "").replace(";", ""); 

        String message = null;

        //String dummy1 = "Jabroni"; // This is the first dummy palindrome string
        //dummy1 = dummy1.toLowerCase();
       // String dummy2 = ""; // This a non palindrome string

        int strLength = input.length(); // This will count the number of characters in a string
        int midCount = strLength / 2; // The "midCount" is divided into half so that we do not loop all the way

        // Initialize the character variables used to compare the chars in the loop
        char bChar; // Will store to check the beginning character
        char eChar; // Will store to check the ending char

        // Initialize a counter variable which will be used to compare
        //System.out.println(dummy1);

        int cCount = 0; // This will count how many chars are similar
        for (int x = 0; x < midCount; x++)
        {

            strLength--; // Reduces the string by 1
            //System.out.println(strLength);
            bChar = input.charAt(x);
            eChar = input.charAt(strLength);

            // If conditionals for comparison of characters
            if (bChar == eChar){
               cCount += 1;
            } 
        }

        // Compare the midpoint with cCount 
        // If they match then the code is a success if not we have failed
        if (cCount == midCount){
            message = "Success! ;-D The string is a Palindrome";
        }
        else 
            message = "It is not a Palindrome. Sorry :-(";

        JOptionPane.showMessageDialog(null, message, "Palindrome App", JOptionPane.INFORMATION_MESSAGE);
    }     
}