The alphabets A, E, I, O and U (small case and upper case) are known as vowels and rest of the alphabets are known as consonants.

Method 1: Program to check if character is vowel or consonant using switch case

import java.util.Scanner;

public class VowelOrConsonantExample {
	public static void main(String[] args) {
		boolean isVowel = false;
		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter a character : ");
		char ch = scanner.next().charAt(0);
		scanner.close();
		switch (ch) {
		case 'a':
			isVowel = true;
			break;
		case 'e':
			isVowel = true;
			break;
		case 'i':
			isVowel = true;
			break;
		case 'o':
			isVowel = true;
			break;
		case 'u':
			isVowel = true;
			break;
		case 'A':
			isVowel = true;
			break;
		case 'E':
			isVowel = true;
			break;
		case 'I':
			isVowel = true;
			break;
		case 'O':
			isVowel = true;
			break;
		case 'U':
			isVowel = true;
		}
		if (isVowel == true) {
			System.out.println(ch + " is  a Vowel");
		} else {
			if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z'))
				System.out.println(ch + " is a Consonant");
			else
				System.out.println("Input is not an alphabet");
		}
	}
}

Output

Enter a character : 
A
A is  a Vowel

Enter a character : 
h
h is a Consonant

Method 2: Program to check if character is vowel or consonant using using if..else statement

import java.util.Scanner;

public class VowelOrConsonantExample {
	public static void main(String[] args) {
		int i = 0;
		Scanner sc = new Scanner(System.in);
		System.out.println("Enter a character : ");

		char ch = sc.next().charAt(0);
		if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I'
				|| ch == 'O' || ch == 'U') {
			System.out.println("Entered character " + ch + " is  Vowel");
		} else if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z'))
			System.out.println("Entered character " + ch + " is Consonant");
		else
			System.out.println("Not an alphabet");
	}
}

Output

Enter a character : 
I
Entered character I is  Vowel

Enter a character : 
V
Entered character V is Consonant

Enter a character : 
;
Not an alphabet