Palindromic substrings-667

class Solution {
    public static boolean isPalindrome(String s){
        int i=0;
        int j = s.length()-1;
        while(i<=j){
            char ch1 = s.charAt(i);
            char ch2 = s.charAt(j);
            if(ch1!=ch2){
                return false;
            }else{
                i++;
                j--;
            }
        }
        return true;
    }
    
    public int countSubstrings(String s) {
        int count=0;
       for(int i=0;i<s.length();i++){
           for(int j=i+1;j<=s.length();j++){
               String str = s.substring(i,j);
               if(isPalindrome(str)==true){
                   count++;
               }
           }
       }
        return count;
    }
    
}