Java Program to Count the Number of Vowels and Consonants in a Sentence

Example: Program to count vowels, consonants, digits, and spaces

 class Main { public static void main(String[] args) { String line = "This website is aw3som3."; int vowels = 0, consonants = 0, digits = 0, spaces = 0; line = line.toLowerCase(); for (int i = 0; i < line.length(); ++i) { char ch = line.charAt(i); // check if character is any of a, e, i, o, u if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u') { ++vowels; } // check if character is in between a to z else if ((ch >= 'a' && ch <= 'z')) { ++consonants; } // check if character is in between 0 to 9 else if (ch >= '0' && ch <= '9') { ++digits; } // check if character is a white space else if (ch == ' ') { ++spaces; } } System.out.println("Vowels: " + vowels); System.out.println("Consonants: " + consonants); System.out.println("Digits: " + digits); System.out.println("White spaces: " + spaces); } }

Output

 Vowels: 7 Consonants: 11 Digits: 2 White spaces: 3

In the above example, we've 4 conditions for each of the checks.

• The first if condition is to check whether the character is a vowel or not.
• The else if condition following if is to check whether the character is a consonant or not. This condition is checked only when the if condition is false.
• The second else if is to check whether the character is between 0 to 9 or not.
• Finally, the last condition is to check whether the character is a space character or not.

For this, we've lowercased the line using toLowerCase(). This is an optimization done not to check for capitalized A to Z and vowels.

We've used length() function to know the length of the string and charAt() to get the character at the given index (position).