无法使用Java将int转换为char

Question

I was given an assignment to generate a random number between 1 to 26 then convert that number to a letter from 'a' to 'z'. the random generating part looks fine but when I try to cast the number to char, I would just get an empty square-like box! why is that?

    import java.util.Random;
    public class NumbersToLetters 
    {
        public static void main(String[] args) 
        {
            Random n;
            int num;
            n=new Random();
    //generating a random number from 1 to 26
            num=Math.abs(((n.nextInt())%26)+1); 
    //cast from int to char
            char myChar = (char) num; 
            System.out.println ("Number - " + num); 
            System.out.println ("Char - " + myChar);

   //I'm sure that my answer is right but no matter what I do,
   //it won't output a letter, all I get is a square-like box..
        }
    }

Answer 1

The character 'a' is not encoded as 1 , but as 97 . You need to add 'a' to a value between 0 and 25 (inclusive) to get the expected result:

num = 'a'+n.nextInt(26);

Answer 2

You're generating a number between 1 and 27 (inclusive). If you look at what those characters correspond to , you'll see that none of them are actually printable.

You should do your calculation as + 'a' instead of + 1

n.nextInt(26) + 'a';

This will give you the correct offset (which happens to be 97) to find the lower case letters.

Answer 3

I'm not a Java guru like others on here, but it might have something to do with not being encoded correctly? Look up UTF-8 encoding and just research type casting