public class IsUpperCase
{
    public static void main(String[] args) 
    {
        char c;

        c = 'A';    // Change this and demo

        if ( 65 <= c && c <= 90 )
            System.out.println("Uppercase letter");
        else
            System.out.println("No an uppercase letter");
        
        if ( 'A' <= c && c <= 'Z' )
            System.out.println("Uppercase letter");
        else
            System.out.println("No an uppercase letter");
        
        if ( Character.isUpperCase(c) )
            System.out.println("Uppercase letter");
        else
            System.out.println("No an uppercase letter");
    }
}