/*
 * CharGenerator.java
 *
 * Created on January 7, 2003, 2:54 PM
 * Modify this file, and turn in it.  Do not change the package name, class name,
 *      or any method signatures.
 */

package project1;

/** Methods related to generating and testing characters, for the Diety of Luck
 *  project.
 *  Valid characters for this application are the 26 standard uppercase characters
 *  used in English.
 *  Note: there are standard Java library methods with signatures like
 *      boolean isUpperCase(char)
 *  Before using them, check carefully to see if their idea of "upper case" is
 *  the same as the one used in this project.
 *
 * @author  dickey
 */
public class CharGenerator {

//    String alphabet;
    static String alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

    /** Creates a new instance of CharGenerator.
     Check that the internal table of upper case letters is plausible. 
     */
    public CharGenerator() {
        assert alphabet.length() == 26; //known length of the English alphabet
        for (int a = 0; a < alphabet.length(); a++) {
            char ch = alphabet.charAt(a);
            assert isEnglishUpperCase(ch);
        }
    //end constructor    
    }
    
    /** Test if the character is a valid uppercase letter of English.
     * @param ch any (Unicode) character
     * @return true iff the character is valid, i.e., in the range A to Z.
     */
    public static boolean isEnglishUpperCase(char c) {
        if (c <= 'Z' && c >= 'A') {
            return true;
        }
        return false;
        //end isEnglishUpperCase
    }
    
    /** Generate a random charachter, drawn from the internally known set of
     * upper case characters.
     * @return a character in the range A to Z.
     */
    public static char randomUpperChar() {
        int alphaIndex = (int) (Math.random() * 26);
        char retChar = alphabet.charAt(alphaIndex);
        assert isEnglishUpperCase(retChar);
        return retChar;
    }

//end CharGenerator
}