Palindrome

A palindrome is a word, phrase, number, or other sequence of characters which reads the same backward or forward. Allowances may be made for adjustments to capital letters, punctuation, and word dividers. Famous examples include "A man, a plan, a canal, Panama!", "Amor, Roma", "race car", "stack cats", "step on no pets", "taco cat", "put it up", "Was it a car or a cat I saw?" and "No 'x' in Nixon"

Java code to validate the Palindrome is as follow : 

/*

 * @sachin

 */

public class Palindrome {

public static boolean isPalindrome(String input) throws Exception{

if(input == null || input.isEmpty()) {

throw new Exception("Invalid input");

}

String str = input.replaceAll("[^a-zA-Z0-9]", "").toLowerCase();

boolean isPalindrome = true;

int i = 0;

int j = str.length();

for(i=0; i< j;i++){

if(str.charAt(i) == str.charAt(j-1)){

j--;

continue;

} else {

isPalindrome = false;

}

}

return isPalindrome;

}

public static void main(String[] args) {

try {

System.out.println("isValidPalindrome=" + isPalindrome("No 'x' in Nixon"));

                        System.out.println("isValidPalindrome=" + isPalindrome("12321"));

                        System.out.println("isValidPalindrome=" + isPalindrome("sachin"));

} catch (Exception e) {

e.printStackTrace();

}

}

}

Output : 

true

true

false