A code I did in high school.

import java.util.Scanner;//importing the Scanner.

public class Letter{//Starting the program.

public static void Letter(){//Initialising the class.

Scanner Letter=new Scanner(System.in);//So that the user can input the letter.

System.out.println("Enter a letter.");//Asking the user for a letter.

final char letter=Letter.next[].charAt(0);//Storing the user input.

switch(letter){//Checkign for the letter that the user input.

case 'A'://If the user had input A.

case 'a'://If the user had input a.

case 'E'://If the user had input E.

case 'e'://If the user had input e.

case 'I'://If the user had input I.

case 'i'://If the user had input i.

case 'O'://If the user had input O.

case 'o'://If the user had input o.

case 'U'://If the user had input U.

case 'u'://If the user had input u.

System.out.print(Letter+" is a vowel.");//Printing an appropriate message.

case 'B'://If the user had input B.

case 'b'://If the user had input b.

case 'C'://If the user had input C.

case 'c'://If the user had input c.

case 'D'://If the user had input D.

case 'd'://If the user had input d.

case 'F'://If the user had input F.

case 'f'://If the user had input f.

case 'G'://If the user had input G.

case 'g'://If the user had input g.

case 'H'://If the user had input H.

case 'h'://If the user had input h.

case 'J'://If the user had input J.

case 'j'://If the user had input j.

case 'K'://If the user had input K.

case 'k'://If the user had input k.

case 'L'://If the user had input L.

case 'l'://If the user had input l.

case 'M'://If the user had input M.

case 'm'://If the user had input m. case 'N'://If the user had input N.

case 'n'://If the user had input n.

case 'P'://If the user had input P.

case 'p'://If the user had input p.

case 'Q'://If the user had input Q.

case 'q'://If the user had input q.

case 'R'://If the user had input R.

case 'r'://If the user had input r.

case 'S'://If the user had input S.

case 's'://If the user had input s.

case 'T'://If the user had input T.

case 't'://If the user had input t.

case 'U'://If the user had input U.

case 'u'://If the user had input u.

case 'V'://If the user had input V.

case 'v'://If the user had input v.

case 'W'://If the user had input W.

case 'w'://If the user had input w.

case 'X'://If the user had input X.

case 'x'://If the user had input x.

case 'Y'://If the user had input Y.

case 'y'://If the user had input y.

case 'Z'://If the user had input Z.

case 'z'://If the user had input z.

System.out.println(Letter+" is a consonant.");//Printing an appropriate message.

default://If anything else happens.

System.out.print("Error.");//Printing an appropriate message.

}//Closing the curly brackets.

}//Closing the curly brackets.

}//Closing the curly brackets.