Count of vowels & consonants in string

public class CountVowelConsonant {  
    public static void main(String[] args) {  
          
        //Counter variable to store the count of vowels and consonant  
        int vCount = 0, cCount = 0;  
          
        //Declare a string  
        String str = "This is a really simple sentence";  
          
        //Converting entire string to lower case to reduce the comparisons  
        str = str.toLowerCase();  
          
        for(int i = 0; i < str.length(); i++) {  
            //Checks whether a character is a vowel  
            if(str.charAt(i) == 'a' || str.charAt(i) == 'e' || str.charAt(i) == 'i' || str.charAt(i) == 'o' || str.charAt(i) == 'u') {  
                //Increments the vowel counter  
                vCount++;  
            }  
            //Checks whether a character is a consonant  
            else if(str.charAt(i) >= 'a' && str.charAt(i)<='z') {    
                //Increments the consonant counter  
                cCount++;  
            }  
        }  
        System.out.println("Number of vowels: " + vCount);  
        System.out.println("Number of consonants: " + cCount);  
    }  
}